JP6163640B2 - Ophthalmic lens manufacturing method and ophthalmic lens - Google Patents

Description

  The present invention relates to a method for manufacturing an ophthalmic lens having a light blocking substance, and an ophthalmic lens having a light blocking substance manufactured by the manufacturing method.

  Ophthalmic lenses such as contact lenses, intraocular lenses, artificial eyes, intracorneal lenses, and fake kick IOLs use light-shielding substances such as pigments, opacifying materials such as titanium dioxide powder, and energy absorbing materials. There is a product.

  In recent years, disposable soft contact lenses that place importance on safety and hygiene have been mass-produced at low cost by the casting method using male and female molds, the spin casting method using a rotating device, etc. Yes. Along with this, fashionable colored contact lenses having a substance that shields light that objectively changes the color or texture of the iris are also gradually spreading.

  As a method of coloring the contact lens, the first lens is spin-cast, colored on the first lens, and then the second lens is spin-cast on the first lens, whereby a colored material is placed between the first and second lenses. A method of sandwiching is described (Patent Document 1). Another coloring method is that the first lens part is manufactured in a mold and the iris shielding part is imprinted or otherwise placed on the first lens part, and then the lens material monomer Is placed over the first lens portion to produce a second lens portion fused with the monomer to the first lens portion and cured to encapsulate the iris shielding portion, and finally the lens is It processes by a standard method (patent document 2). Furthermore, as a method of applying a colored pattern on both surfaces of the lens, the pattern is fixed to both the rear mold and the front mold, and then a monomer mixture for lens formation is supplied to each mold, and each monomer mixture Is partially polymerized, thereby fixing the pattern to the rear and front surfaces of the lens, respectively. Next, the two molds are combined, and the superposed rear and front lens-forming monomer mixtures are polymerized and bonded together to complete curing to form a colored contact lens having a pattern on both sides (Patent Document 3). ) Etc.

  This time, the present inventor used to harden the lens forming liquid on at least a part of the lens forming surface side of either the male type or the female type when manufacturing an ophthalmic lens having a light shielding substance. An ophthalmic lens by adhering a substance that shields light to be applied, and then filling the lens-forming liquid between the male mold and the female mold, and then irradiating the light to cure the lens-forming liquid. As a result of carrying out the method for producing a lens, many bubbles were generated, and a good lens could not be obtained. Therefore, the cause of this is investigated, and an inexpensive and reliable measure for suppressing bubbles is required.

Japanese Patent Publication No. 48-10090 Japanese Patent Laid-Open No. 02-181723 Japanese Patent Laid-Open No. 02-134612

  An object of the present invention is to attach a substance that shields light used when curing the lens forming liquid to at least a part of the lens forming surface side of either the male mold or the female mold. In the manufacturing method of an ophthalmic lens that does not cause bubble defects when the lens forming liquid is filled between the female molds and then the lens forming liquid is cured by irradiating the light. An object of the present invention is to provide a manufactured ophthalmic lens.

  Another object of the present invention is to manufacture a safe and high-quality ophthalmic lens in a short time, at a low cost, at a high yield rate, and to produce an ophthalmic lens manufactured by this manufacturing method. The purpose is to provide a large amount, at a low cost and in a high quality according to the demand of the company.

  The first manufacturing method of the present invention for solving the above problem is used when (A) the lens forming liquid is cured on at least a part of either the male mold or the female mold on the lens forming surface side. (B) filling the lens forming liquid between the male mold and the female mold; and (C) irradiating the light to apply the lens forming liquid. A step of curing, and in the step (C), at least the light is directed from the direction of the mold to which the light shielding substance is not attached to the mold to which the light shielding substance is attached. It is to irradiate. The ophthalmic lens of the present invention is manufactured by the first manufacturing method.

  In the second manufacturing method of the present invention, the intensity of the light reaching the lens forming liquid in the first manufacturing method is such that the light is shielded from the direction of the mold to which the light shielding material is attached. Irradiate from the direction of the mold where the light-shielding substance is not attached to the mold where the light-shielding substance is attached from the intensity of the light emitted toward the mold where the substance is not attached. The strength that is given is stronger. The ophthalmic lens of the present invention is manufactured by the second manufacturing method. The “intensity of the light reaching the lens forming liquid” used in the present invention means the intensity of the light reaching the lens forming liquid when the substance that blocks the light is removed. Since the irradiated light is attenuated by obstacles such as the distance to the lens formation liquid and the mold, it is necessary to consider the attenuation amount.

  In the third manufacturing method of the present invention, the intensity of the light reaching the lens forming liquid in the second manufacturing method is such that the light is shielded from the direction of the mold to which a substance that shields the light is attached. It is irradiated from the direction of the mold where the light shielding substance is not attached to the mold where the light shielding substance is attached from the intensity irradiated toward the mold where the substance is not attached. The strength is 1.5 times or more. The ophthalmic lens of the present invention is manufactured by the third manufacturing method.

  According to a fourth manufacturing method of the present invention, in the first to third manufacturing methods, the lens forming liquid shrinks in volume by 1% or more upon curing. The ophthalmic lens of the present invention is manufactured by the fourth manufacturing method.

  According to a fifth manufacturing method of the present invention, in the fourth manufacturing method, the volume of the lens forming liquid contracts by 3% or more upon curing. The ophthalmic lens of the present invention is manufactured by the fifth manufacturing method.

  According to a sixth manufacturing method of the present invention, in the fifth manufacturing method, the lens forming liquid contracts by 5% or more when cured. The ophthalmic lens of the present invention is manufactured by the sixth manufacturing method.

  According to a seventh manufacturing method of the present invention, in the first to sixth manufacturing methods, the mold to which the light shielding substance is attached has a coating layer between the light shielding substance and the mold. Is to have. The ophthalmic lens of the present invention is manufactured by the seventh manufacturing method.

  According to an eighth manufacturing method of the present invention, in the seventh manufacturing method, the surface of a contact lens, which is a kind of ophthalmic lens, is generally composed of a central optical surface and a peripheral surface around it. Is to cover at least all the optical surfaces on one side of the contact lens. The ophthalmic lens of the present invention is manufactured by the eighth manufacturing method.

  According to a ninth manufacturing method of the present invention, in the eighth manufacturing method, the covering layer covers 10% to 99.9% of the peripheral surface in addition to all the optical surfaces on one side of the contact lens. Preferably covering 50% to 99.8% of the peripheral surface, more preferably covering 80% to 99.7% or less of the peripheral surface, most preferably 95% to 95% of the peripheral surface. Covering 99.7%. The ophthalmic lens of the present invention is manufactured by the ninth manufacturing method.

  According to the manufacturing method of the present invention, a substance that blocks light used for curing the lens forming liquid is attached to at least a part of either the male mold or the female mold on the lens forming surface side, and then the male mold When the lens forming liquid is filled between the female mold and the female mold, and then the light is irradiated to cure the lens forming liquid, it does not cause bubble defects or reduces bubble defects for ophthalmic use. A lens can be manufactured.

  In addition, according to the manufacturing method of the present invention, an ophthalmic lens having a substance that blocks light used for curing the lens forming liquid on at least a part of the lens forming surface side can be obtained in a short time at a low cost with a high yield rate. The ophthalmic lens manufactured by this manufacturing method can be manufactured in large quantities, at low cost and with high quality according to the demands of consumers.

FIG. 1 is a view showing an example in which a light shielding substance used for curing a lens forming liquid is attached to the male lens forming surface used in the method for producing an ophthalmic lens of the present invention. is there. FIG. 2 is a diagram showing an example of a method for manufacturing a contact lens of the present invention. FIG. 3 is a diagram showing an example of a design of an irised contact lens manufactured by the manufacturing method of the present invention. FIG. 4 is a diagram showing another example of the design of an iris contact lens manufactured by the manufacturing method of the present invention.

  In the present invention, the lens forming liquid filled between the male mold and the female mold is irradiated with light to cure the lens forming liquid. The mold at this time is mainly formed from a resin that transmits light such as PP, PE, polystyrene, and nylon. However, if the lens can be manufactured through transmission of the light to be irradiated, inorganic materials such as glass and quartz are used. May be formed. Further, the male mold and the female mold may be formed of the same material, or may be formed of different materials. Furthermore, one type of lens forming surface or both types of lens forming surfaces may be modified by plasma treatment or the like before use. By making both molds different materials or modifying them, when the mold is divided, the lens is fixed to only one mold, the lens is easily removed from the mold, the lens surface is made hydrophilic, etc. This is because an effect is obtained.

  As the light used in the present invention, ultraviolet rays having a wavelength of about 360 nm are often effective, but electromagnetic waves such as ultraviolet rays having a wavelength shorter than 360 nm, visible light having a long wavelength, and infrared rays can be appropriately used depending on the lens forming liquid and the mold. . Further, as shown in FIG. 2, the direction of irradiation is preferably a direction perpendicular to the lens. This is because the lens is uniformly irradiated, so that the curing becomes uniform. Although the method of irradiating with the point light source radially from the center of the lens sphere is preferable as the most uniform irradiation method, there is a problem that the intensity of the point light source is insufficient.

  One of the male mold and the female mold of the present invention has a substance that shields light used for curing at least at a part on the lens forming surface side. As a raw material for shielding light used for curing, pigments used when objectively changing the color or texture of the iris, opacifying materials such as titanium dioxide powder, lens power, etc. There is an energy absorbing material for adjustment, but it is not limited to these.

  As the material for shielding light used for curing, the shielding raw material may be used alone, but in general, the shielding raw material includes a monomer, a polymer, a thickener, a polymerization initiator, As a mixture to which a solvent or the like is added, it is transferred, arranged, or applied to a desired position on the lens forming surface side of the mold with a brush or a pad. Or it prints with an inkjet printer etc. Then, it is not mixed at all with the lens forming solution used after that, or is dried or cured in advance so as to form a film shape so that it can be mixed appropriately and have a desired shape, sharpness, or pattern. Alternatively, the viscosity may be increased. When used as a mixture, the shielding raw material enters the inside of the lens, so that it is avoided to be exposed to the outside from the lens surface, not only does not peel off during use, but also improves the user's wearing feeling by smoothing the lens surface, Safety can also be improved.

  In addition, a coating layer is provided in advance on the lens forming surface of the mold on the side to which a substance that blocks light used for curing is attached at least on the lens forming surface side, and the light is shielded on the coating layer. It is preferable to produce an ophthalmic lens that also contains the coating layer by applying the substance to be applied. The covering layer may contain a substance that shields the light. This is because it is possible to completely avoid exposing the light shielding substance from the lens surface. FIG. 1 shows an example in which a substance that blocks light is attached to the male lens forming surface side. (A) is an example in which the substance that blocks light is directly attached to the male lens forming surface side. (B) shows an example in which a substance that shields the light is made to adhere to the coating layer on the male lens forming surface side. (C) shows an example in which the coating layer having the light shielding substance attached to the outer surface is attached to the male lens forming surface. FIG. 1 shows an example in which the light shielding material is attached to the male lens forming surface side. However, the light shielding material may be attached to the female lens forming surface side. Further, the substance that shields the light is substantially attached to the lens forming surface side of one type of male and female, and the material that shields the light on the lens forming surface side of the other type is formed by the light of the lens forming liquid. You may make it adhere slightly to such an extent that it does not affect hardening. Examples of slightly attaching the light shielding substance to the extent that it does not affect photocuring include symbols and characters representing product names, standards, and the like. Since these symbols and characters are slightly attached, it is preferable to make the color different from the color of the substance that shields the light on the opposite surface so as to stand out.

  The covering layer preferably completely covers the light shielding material, but more preferably covers not only the light shielding material but also all the optical parts on one side of the ophthalmic lens. The ophthalmic lens is required to have a high-precision power with no distortion, the optical part has a narrow range of about 10 mm or less, and a wider optical part is required when moving in the eye like a contact lens. This is because it is desirable that the portion and the peripheral portion subsequent thereto are integrally formed so as not to be distorted.

  The covering layer preferably covers 10% to 99.9% of the peripheral surface in addition to all the optical surfaces on one side of the contact lens, and covers 50% to 99.8% of the peripheral surface. More preferably, it is more preferable to cover 80% to 99.7% or less of the peripheral surface, and most preferable to cover 95% to 99.7% of the peripheral surface. As described above, it is optically effective to cover a larger area, but conversely, when the lens forming liquid is cured to produce a final lens shape, the lens forming liquid part is replaced with the covering layer part. This is because it is not preferable that the covering layer covers 100% of the peripheral surface because it can be produced smoothly by suppressing the generation of burrs and the like at the contact lens edge by making it larger.

  The method for producing an ophthalmic lens of the present invention is applicable to contact lenses, intraocular lenses, artificial eyes, intracorneal lenses, and fake kick IOLs, and is particularly suitable for contact lenses. This is because the contact lens is detachable and can be applied to the surface of the eye to change its appearance. Also, in recent years, disposable soft contact lenses have become widespread and in great demand.

  The method for producing an ophthalmic lens of the present invention is basically a casting method in which a lens forming liquid filled between a male mold and a female mold is irradiated with light and cured. General methods for producing ophthalmic lenses are classified into a cutting polishing method, a spin casting method, and a casting method. The cutting and polishing method is the oldest manufacturing method, and is still used when forming hard materials with high precision, but is not suitable for low-priced mass production. In addition, the spin cast method has a difficulty in finishing the edge, and remains an anxiety factor in the reproducibility of the frequency. Therefore, most of the disposable soft contact lenses are currently produced by the casting method. However, it goes without saying that the manufacturing method in which the cutting and polishing method or the spin casting method is combined with the casting method belongs to the present invention as long as the manufacturing method of the present invention is used.

  Generally, heat or light is used for curing the lens forming liquid. In general, heat is used at a temperature of about 30 to 100 ° C., but it may be accompanied by deformation of the mold and may require a high-cost resin having a high heat deformation temperature. Moreover, several tens of minutes to several hours are required for curing, and productivity is poor. Since light cures in the vicinity of room temperature in a few seconds to several minutes, it has advantages such as high productivity and the use of an inexpensive resin with a low softening point such as PP and PE. Therefore, in the method for producing an ophthalmic lens of the present invention, light is used for curing the lens forming liquid.

  The “lens forming liquid” used in the present invention means that a substance that shields light is attached to at least a part of the lens forming surface side of either the male mold or the female mold, and then the male mold and the female mold are used. It means a liquid filled between the male mold and the female mold, which is used when an ophthalmic lens is manufactured by filling the liquid between and irradiating the light to cure the liquid. Therefore, the ophthalmic lens of the present invention includes a cured product of a lens forming liquid and a substance that shields light, and may also include the above-described coating layer.

  The constituent components of the lens forming liquid of the soft contact lens of the present invention include (A) a compound having a functional group as a main component or subcomponent of the lens, and (B) a plurality of functionalities that affect the stability and strength of the lens. A compound having a group, (C) a compound that causes curing, and (D) a compound or a solvent that gives a special function to the lens or the lens-forming liquid are used.

  Examples of the compound having a functional group serving as a main component or subcomponent of the lens (A) include 2-hydroxyethyl methacrylate (hereinafter referred to as 2-HEMA), methacrylic acid, and 2,3-dihydroxypropyl methacrylate (hereinafter referred to as glycerol). MA), N-vinylpyrrolidone (hereinafter referred to as N-VP) and hydrated agent (A1) such as dimethylacrylamide (hereinafter referred to as DMAA), tris (trimethylsiloxy) silylpropyl methacrylate (hereinafter referred to as Tris MA) Oxygen permeation, such as low molecular weight silicone monomers, such as hundreds to tens of thousands of siloxane units, functional groups, and optionally hydrophilic units. The property improver (A2) is used alone or in combination. When mixed and used, good copolymerizability between the compounds to be used is preferable because the refractive index and the swelling ratio upon hydration become uniform and a high-quality lens excellent in transparency and lens shape stability is preferable. The amount of these compounds (A) used is at least 5% or more, generally 40 to 99%. If the silicone system is not used, the oxygen permeability is not high, but the water-containing soft contact lens is suitable for comfortable wearing in a short time. Use of a silicone system increases oxygen permeability, but it is hydrophobic and adsorbs a large amount of fat components, making it easy to adhere to the eyes. Is.

  Examples of the compound (B) having a plurality of functional groups that affect the stability and strength of the lens include ethylene glycol di (meth) acrylate (hereinafter referred to as EDMA), diethylene glycol di (meth) acrylate, trimethylolpropane tri Compound (B1) obtained by reaction of polyhydric alcohol with acid or alcohol having a functional group, such as (meth) acrylate and ethylene glycol (meth) acrylate allyl ether, medium having two or more functional groups The polymer compound (B2) and the compound (B3) having two or more functional groups such as divinylstyrene are used alone or in combination. If the amount used is too small, the lens may be dissolved in water or the like, or the stability of the lens may be insufficient. If the amount used is too large, the number of cross-linking points will increase, the lens will become brittle, and shortcomings such as breakage will become noticeable. The amount of (B) used is generally 0.02 to 10%.

  As the compound causing the curing of (C), a photopolymerization initiator, a photosensitizer or the like is used. The photopolymerization initiator is an alkylphenone (C1) such as 2-hydroxy-2-methyl-1-phenyl-propan-1-one (hereinafter referred to as HMPP), 2,4,6-trimethylbenzoyl-diphenyl- There are titanocene systems (C2) such as phosphine oxide. Examples of the photosensitizer include benzophenone derivatives (C3) such as benzophenone. The compound (C) that causes these curings is considered in consideration of compatibility with a lens forming liquid such as a main component, subcomponent, a plurality of functional groups, a crosslinking agent having a plurality of functional groups, and a solvent, and the like. Used alone or in combination. In addition, when the lens-forming solution contains a light absorber such as an ultraviolet absorber or a dye, it is cured with a wavelength region other than the absorption wavelength of these compounds, for example, electromagnetic waves such as ultraviolet rays, visible rays, and infrared rays. It is preferable to select a wavelength to be caused and a compound suitable for the wavelength. If the amount of the compound (C) that causes curing is too small, it takes too much time for curing, and if it is too large, the molecular weight of the cured product becomes too short, which is not preferable because the stability and strength of the lens are lowered. The curing speed is affected by the amount and type of the compound that causes curing in the lens forming liquid and the intensity and wavelength of the reaching light. The compound that causes curing is 0.01% or more, and generally 0.1 to 5% is used.

As the wavelength of light for curing the lens forming liquid, ultraviolet rays of about 360 nm are often effective, but when the lens forming liquid contains a light absorber such as an ultraviolet absorber or a dye, these compounds are used. It is preferable to cure by irradiating with a wavelength other than the absorption wavelength. Therefore, electromagnetic waves such as ultraviolet rays, visible rays, and infrared rays are appropriately used depending on the lens forming liquid. In addition, the intensity of light for curing the lens forming liquid varies depending on the type and concentration of the compound (C) that causes curing and the components and concentrations of the lens forming liquid, but is generally 0.01 to 100 mW / cm ^2. Preferably, 0.1 to 50 mW / cm ² is used. Further, the time for curing the lens forming liquid is generally 1 second to 100 minutes, preferably 10 seconds to 20 minutes. This is because if the curing time is too short, it may polymerize explosively in a short period of time and bubbles may be generated due to high heat, the mold may be deformed, or the lens strength may be reduced due to insufficient polymerization. This is because if the curing time is too long, the productivity is lowered and a large-scale facility or place is required.

  As an option, a compound or a solvent that gives a special function or the like to the lens or lens forming liquid of (D) is used. Examples of these include hydrophilic polymers (D1) such as polyvinylpyrrolidone that increase the hydrophilicity of silicone hydrogels, thickeners (D2) used for the purpose of controlling bleeding such as colorants, Solvent (D3) used in the so-called wet mold for stabilizing the shape, solvent (D4) for the purpose of easily removing the cured lens from the mold, and compatibility between the silicone compound and the hydrophilic compound. There is a solvent (D5) for improving, and these are used alone or in combination. The amount of these compounds and solvent (D) used is suitably in the range of 0 to 90% depending on the purpose.

  This time, when the present inventor made a prototype of an ophthalmic lens having a light shielding material, the light shielding material was attached to at least a part of either the male or female lens-forming surface side. When a method for producing an ophthalmic lens was performed by irradiating and curing the lens forming liquid filled between the male mold and the female mold using a mold, a large number of bubbles were generated. I couldn't get a lens.

  When the generation state of the bubbles was observed, a large number of the bubbles were generated at the boundary between the portion where the light shielding substance was adhered and the portion where the substance was not adhered. The mechanism of bubble generation was examined by changing the irradiation direction of the light, the shape of the substance that shields the light, and the type of the lens forming liquid, and inferred as follows. During polymerization, if a portion where the irradiated light reaches a large amount of the lens-forming liquid and a portion where it reaches a little are mixed, the portion that has reached a large amount will start to polymerize first, and the viscosity of the polymerized portion will increase and molecular motion will be suppressed. Therefore, the polymerization proceeds progressively, and heat of polymerization is generated to partially increase the temperature, and in the polymerized portion, the low boiling point monomer, solvent, dissolved gas, and the like become vaporized or microbubbles. Then, the vaporized product or microbubbles move to the lens forming liquid side where the irradiated light hardly reaches and the polymerization is slow. On the other hand, polymerization shrinkage occurs as the polymerization progresses, and the male mold and female mold fit more closely, and one mold bites into the other mold at the edge of the lens, increasing the airtightness in the mold and increasing the lens forming liquid. Is in a reduced pressure state, and low-boiling monomers, solvents, dissolved gases, and the like are vaporized even in a lens-forming solution that is slow to reach irradiated light and slow in polymerization. For this reason, vaporized substances or microbubbles that have traveled from the side of the lens forming solution that has been irradiated with a lot of irradiated light and that have been rapidly polymerized cannot be dissolved in the lens forming solution that has a low amount of irradiated light and that has been slowly polymerized. At the boundary between the part to which the substance to be adhered is attached and the part to which the substance is not attached is agglomerated into bubbles.

  The generation mechanism of the bubbles is inference and has not been verified, but it is considered that various factors are related from this inference, and various solutions can be considered. It seems to have a certain value. As a first solution that can be considered from this reasoning, it is conceivable to reduce the bubble element by excluding the low boiling point monomer, solvent and dissolved gas in the lens forming solution, but the low boiling point monomer is necessary for the physical properties of the lens. If this is the case, it cannot be excluded, and the solvent is added for some reason and cannot be easily excluded, and this solution is not universal. Also, as a second solution, a method of increasing the lens thickness to speed the movement of the lens forming liquid and bubbles in the mold is conceivable. However, increasing the lens thickness reduces the oxygen transmission amount of the contact lens. And not desirable. Further, as a third solution, a method of adding a large amount of a high-boiling solvent in the lens forming liquid to reduce the polymerization shrinkage of the lens forming liquid and reducing the degree of decompression can be considered, but the mold becomes large. This is not preferable because not only the material cost of the mold is increased, but also the cost and time are required for removing the solvent, and the stability of the lens after hydration is deteriorated. However, as long as these first to third solutions are used alone or in combination, and the manufacturing method of the present invention is also used, the present invention belongs to the present invention.

  As a result of diligent examination of the method for solving the bubbles, the present inventor has surprisingly invented a manufacturing method that does not have the above-described drawbacks, is inexpensive, surely and universally solved. is there. That is, the first manufacturing method of the present invention is (A) a substance that shields light used for curing the lens forming liquid on at least a part of either the male or female lens forming surface side. (B) filling the lens forming liquid between the male mold and the female mold; and (C) irradiating the light to cure the lens forming liquid. Including, in the step (C), irradiating at least the light from the direction of the mold not adhering to the light shielding material toward the mold adhering to the light shielding material. . A mold to which the light shielding substance is attached by irradiating the light from a direction of the mold to which the light shielding substance is not attached to a mold to which the light shielding substance is attached. Since the polymerization of the lens forming liquid in the lens forming liquid is more uniform than in the case where the light is irradiated only from the direction toward the mold to which the substance that shields the light is not attached, Does not become bubbles, or becomes microbubbles that cannot be confirmed even with a microscope, reducing bubble defects in the lens. As shown in FIG. 3, the light shielding substance may be a single continuous ring, but may be a plurality of aggregates as shown in FIG. When irradiating the light from the direction of the mold to which the light shielding material is attached toward the mold to which the light shielding material is attached, the larger the surface area of one of the light shielding materials, the larger the lens. The range in which the amount of light reaching the forming liquid is small is widened, which promotes the generation of bubbles.

  In the second manufacturing method of the present invention, the intensity of the light reaching the lens forming liquid in the first manufacturing method is such that the light is shielded from the direction of the mold to which the light shielding material is attached. It is irradiated from the direction of the mold where the light shielding substance is not attached to the mold where the light shielding substance is attached from the intensity irradiated toward the mold where the substance is not attached. The strength that is present is stronger. As a result, compared to the case where the intensity of the irradiated light is weak, the difference in the amount of irradiated light reaching the part where the substance that shields the light of the lens forming liquid is adhered and the part where it is not adhered is reduced, and the lens Since the polymerization of the forming liquid becomes more uniform, the vaporized product does not become bubbles, or becomes microbubbles that cannot be confirmed with a microscope, thereby further reducing bubble defects in the lens.

  In the third manufacturing method of the present invention, the intensity of the light reaching the lens forming liquid in the second manufacturing method is such that the light is shielded from the direction of the mold to which a substance that shields the light is attached. It is irradiated from the direction of the mold where the light shielding substance is not attached to the mold where the light shielding substance is attached from the intensity irradiated toward the mold where the substance is not attached. The strength is 1.5 times or more. As a result, the difference in the amount of irradiated light reaching the part where the substance that shields the light of the lens forming liquid is attached and the part where it is not attached is further reduced than in the second manufacturing method, and the polymerization of the lens forming liquid is reduced. Since it becomes more uniform, the vaporized material does not become bubbles, or becomes minute bubbles that cannot be confirmed with a microscope, further reducing bubble defects in the lens. The intensity of the irradiated light that reaches the lens forming liquid is irradiated from the direction of the mold to which the light shielding substance is attached toward the mold to which the light shielding substance is not attached. Relative to the intensity, the intensity irradiated from the direction of the mold to which the light shielding substance is not adhered to the mold to which the light shielding substance is adhered is more preferably 3 times or more. It is more preferable that the light is not irradiated from the direction of the mold on which the light blocking substance is attached to the mold on which the light blocking substance is not attached, and the light blocking substance is attached. It is most preferable that the light is irradiated only from the direction of the mold that is not directed toward the mold to which the substance that blocks light is attached.

  According to a fourth manufacturing method of the present invention, in the first to third manufacturing methods, the lens forming liquid shrinks in volume by 1% or more upon curing. Even if the volume of the lens-forming liquid shrinks by 1% or more when cured, for the reason described in the first to third manufacturing methods, the polymerization of the lens-forming liquid becomes uniform. Or microbubbles that cannot be confirmed with a microscope, reducing the bubble defects in the lens.

  According to a fifth manufacturing method of the present invention, in the fourth manufacturing method, the volume of the lens forming liquid contracts by 3% or more upon curing. Even if the volume of the lens forming liquid shrinks by 3% or more when cured, for the reason described in the fourth manufacturing method, because the polymerization of the lens forming liquid becomes uniform, the vaporized state does not become bubbles, Or it becomes a micro bubble which cannot be confirmed with a microscope, and the bubble defect of a lens is reduced.

  According to a sixth manufacturing method of the present invention, in the fifth manufacturing method, the lens forming liquid contracts by 5% or more when cured. Even if the volume of the lens-forming liquid shrinks by 5% or more when cured, for the reason described in the fifth manufacturing method, because the polymerization of the lens-forming liquid becomes uniform, the vaporized state does not become bubbles, Or it becomes a micro bubble which cannot be confirmed with a microscope, and the bubble defect of a lens is reduced.

  According to a seventh manufacturing method of the present invention, in the first to sixth manufacturing methods, the mold to which the light shielding substance is attached has a coating layer between the light shielding substance and the mold. That is. It is possible to completely prevent the light shielding substance from being exposed from the lens surface by reducing the bubble defect of the lens by the first to sixth manufacturing methods and manufacturing the ophthalmic lens including the coating layer. It is because it can do.

  According to an eighth manufacturing method of the present invention, in the seventh manufacturing method, the coating layer covers at least all optical surfaces on one side of the contact lens. This is because, in addition to the advantage of the seventh manufacturing method, it is advantageous to obtain an ophthalmic lens having a high precision power.

  According to a ninth manufacturing method of the present invention, in the eighth manufacturing method, the coating layer includes at least 10% to 99.9% of the peripheral surface in addition to all the optical surfaces on one side of the contact lens. Covering 50% to 99.8% of the peripheral surface, more preferably covering 80% to 99.7% or less of the peripheral surface, most preferably 95 of the peripheral surface. % To 99.7% or less. This is because, in addition to the advantage of the eighth manufacturing method, it can be smoothly manufactured while suppressing the occurrence of burrs and the like of the ophthalmic lens.

For example, as shown in FIG. 2, the method for manufacturing a contact lens in the case where the mold to which the light shielding substance of the present invention is attached has a coating layer between the light shielding substance and the mold. The following steps are included.
(1) A step of filling the female mold B with a coating layer forming liquid in order to form a coating layer.
(2) The male mold A for forming the inner surface of the contact lens is fitted to the female mold B, light is irradiated from the female B direction to the male A direction to cure the coating layer forming liquid, Forming step.
(3) A step of removing the female mold B and attaching a substance that shields the light to the rear surface side of the coating layer whose front side is fixed to the male mold A.
(4) A step of filling the contact mold forming liquid into the female mold C for forming the outer surface of the contact lens.
(5) A material that shields light from the direction of the female mold C, in which the male mold A having a coating layer to which the light shielding substance is attached, is fitted to the female mold C and no light shielding substance is attached thereto. Irradiating the light toward the direction of the attached male mold A, curing the contact lens forming liquid, and forming a cured contact lens intermediate product.
(6) A step of opening the male mold A and the female mold C and taking out the cured contact lens intermediate product having the light shielding substance.

  When the coating layer forming solution in the step (1) has the same composition as the contact lens forming solution in the step (4), the physical properties of both cured products are approximated, which is advantageous in terms of stability such as product specifications. is there. Further, by forming the coating layer forming liquid as a liquid mainly containing hydrophilic 2-hydroxyethyl methacrylate and not containing a hydrophobic silicone component, and the contact lens forming liquid as a liquid containing a hydrophilic component and a silicone component. The inner surface side of the contact lens may be a hydrogel that does not contain a silicone component with excellent wearing feeling, and the middle and outer surface sides may be a silicone hydrogel with excellent oxygen permeability. Similarly, by forming a coating layer consisting only of a hydrophilic component that does not substantially contain a hydrophobic component on the outer surface side of the lens, the inner surface side and the outer surface side of the contact lens have a silicone component excellent in wearing feeling. It is also possible to use a hydrogel that does not contain a silicone hydrogel having excellent oxygen permeability in the middle. At this time, in order not to cause distortion or peeling at the boundary between the coating layer and the cured product layer of the lens forming liquid, (b) the coating layer is made thin so as to follow the cured product layer of the lens forming solution, or (b) the boundary And (ii) physical properties such as moisture content and linear swelling rate of both layers may be approximated by impregnating and crosslinking with each other. In addition, although a coating layer may be fixed to the female type instead of the male type, for the sake of explanation, the example is fixed to the male type.

  In the steps (1) to (2), a coating layer was formed on the male mold A, and in the step (3), the light shielding substance was attached to the rear surface side of the coating layer. The step (2) may be eliminated, and the substance that shields the light may be directly attached to the male mold A or the female mold C in the process (3). When attached to the female mold C, the liquid mixture containing the substance that blocks light is fixed to the outer surface side of the contact lens, and there is no chance of direct contact with the cornea, which is advantageous in terms of safety.

  The method for producing an ophthalmic lens and the ophthalmic lens of the present invention are as described above. The effects of the present invention will be described below with reference to some examples.

A coating layer forming solution P1 (2-HEMA 59 w / w%, glycerol MA 30 w / w%, EDMA 0.5 w / w%, HMPP 0.5 w / w%, glycerin 10 w / w) on PP female mold B with a polymerization shrinkage of 6% %) Was placed in a male P type PP made by plasma treatment, and light (center wavelength 365 nm, 3 mW / cm ² ) was irradiated from female B to male A in a nitrogen atmosphere for 5 minutes. Then, the coating layer forming liquid P1 between both molds was cured, and both molds were separated. The coating layer attached to the male mold A is designed to have a front curvature of 6.6 mm, a rear curvature of 6.6 mm, a center thickness of 0.024 mm, and an outer diameter of 10.88 mm. On the rear surface of the covering layer, the light shielding material S1 (2) in the shape of FIG. 3 (sphere radius 6.6 mm, inner diameter 6.15 mm, outer diameter 10.00 mm, area 63 mm ² ). -HEMA 30 w / w%, iron oxide 40 w / w%, titanium oxide 20 w / w%, thickener 10 w / w%) is printed on the back surface of the coating layer so as to have a thickness of 10 μm, and about 10 minutes in a blower. It was left at 25 ° C. The surface of the printed material S1 that shields the light was observed to be dry. 35 μl of the P1 liquid as a lens forming liquid is put in a PP female mold C, and is fitted with a male mold A to which a coating layer to which the light shielding substance S1 is left standing in a blower is attached, and is in a nitrogen atmosphere. Below, the said light was irradiated for 5 minutes toward the male type A from the female type | mold C, and the said lens formation liquid P1 was hardened. The outer diameter of the cured lens forming liquid is designed to be 10.92 mm. Subsequently, both molds were separated, and eight contact lens intermediate products fixed to the male mold A were inspected with a microscope 10 times from both the front and rear surfaces of the male mold A, but no eight bubbles were detected. When the male mold A to which the contact lens intermediate product was fixed was immersed in 5 ml of purified water, the contact lens intermediate product was swollen and detached from the male mold A. The swollen contact lens intermediate product was immersed in 5 ml of fresh purified water for 10 minutes at room temperature. The operation of immersing in 5 ml of fresh purified water at room temperature for 10 minutes was carried out 5 times to remove the eluting components in the contact lens intermediate product. The contact lens intermediate product from which the eluent has been removed is placed in a hollow in a PP container containing 1.5 ml of purified water containing 0.9% NaCL and 0.03% ethylenediaminetetraacetic acid 3Na, and sealed with a multilayer film. And autoclaving at 121 ° C. for 20 minutes. After cooling, the multilayer film was peeled off and the contact lens was inspected. As a result, eight good products having a power of −3.00 D, a center thickness of 0.11 mm and a diameter of 14.2 mm and having no bubbles or distortion were obtained.

  (Comparative Example 1) The same procedure as in Example 1 was performed except that the light was irradiated from the male mold A toward the female mold C when the lens forming liquid P1 was cured. Bubble defects were confirmed with the naked eye on 6 out of 8 contact lens intermediate products attached to the male mold A, and bubble defects were confirmed on all 8 with a 10 × microscope.

When the lens forming liquid P1 is cured, it is ² mW / cm ² from the female mold C to the male mold A and 1 mW / cm ² from the male mold A to the female mold C at the same wavelength as described above. The same procedure as in Example 1 was performed except that intense light was irradiated. Air bubbles were not confirmed on all 8 contact lenses, and the product was determined to be good.

  Example 1 except that a lens forming solution L2 (2-HEMA 50 w / w%, EDMA 0.5 w / w%, HMPP 0.5 w / w%, glycerin 49 w / w%) having a polymerization shrinkage rate of 3% was used. Went to. Air bubbles were not confirmed in all 8 contact lenses, and the product was determined to be good.

  Except for using coating layer forming solution P2 (2-HEMA 69 w / w%, EDMA 0.5 w / w%, photopolymerization initiator 0.5 w / w%, 1-octanol 30 w / w%) with a polymerization shrinkage of 6% In the same manner as in Example 1, a male mold A having a coating layer on which a substance S1 that shields light left in a blower was printed was obtained. PP female mold C with lens forming solution L3 (compound 40w / w%, tris MA 20w / w%, DMAA 39w / w%, EDMA 0.5w / w) (w%, HMPP 0.5 w / w%) was put in 30 μl, fitted with the male mold A, and irradiated with the same light from the female mold C toward the male mold A for 5 minutes in a nitrogen atmosphere. Irradiation was performed to cure the liquid L3. The contact lens intermediate product is designed to have a center thickness of 0.08 mm and an outer diameter of 10.92 mm. When both molds were separated, the contact lens intermediate product adhered to male mold A. The contact lens intermediate product was treated in the same manner as in Example 1 to obtain eight contact lenses having a hydrogel with excellent wear feeling on the inner surface and a silicone hydrogel with excellent oxygen permeability on the intermediate and outer surfaces. Air bubbles were not confirmed on all 8 contact lenses, and the product was determined to be good.

  The production method of the present invention can be used in a process for producing an ophthalmic lens having a light shielding material such as an iris contact lens in a mold at a low cost and in a large amount at a low cost.

DESCRIPTION OF SYMBOLS 10 Covering layer formation liquid 11 Covering layer 12 Light shielding substance 13 Contact lens forming liquid 14 Contact lens intermediate product which has light shielding substance

Claims (4)

A method of manufacturing an irised contact lens comprising:
(A) at least a portion of the male and female one lens forming surface of a material to shield the light to be used to cure the lens forming liquid contracts volume of 3% or more when cured, annular A process of adhering as one continuous body or a plurality of aggregates (excluding cases in which symbols and characters representing product names, standards, etc. are adhered so as not to affect the curing of the lens forming liquid by light );
(B) filling the lens forming liquid between the male mold and the female mold; and (C) curing the lens forming liquid by irradiating the light.
In the step (C), the light is irradiated at least from the direction of the mold to which the light shielding substance is not attached to the mold to which the light shielding substance is attached. A manufacturing method of contact lenses with iris to prevent defective bubbles .
In the step (C), the intensity of the light reaching the lens forming liquid is irradiated at an intensity of 0.01 to 100 mW / cm ² for 1 second to 100 minutes, and a substance that shields the light is attached. The material that shields the light from the direction of the mold that does not have the substance that shields the light adheres from the intensity irradiated to the mold that does not have the substance that shields the light from the direction of the mold that adheres. 2. The method for producing an iris contact lens for preventing bubble defects according to claim 1, wherein the intensity irradiated toward the mold is stronger.
Type material for shielding the light is attached prevents bubbles defects according to claim 1 or 2, characterized in Rukoto which have a coating layer between the material and the mold to shield the light Manufacturing method of contact lens with iris .
4. The method of manufacturing an iris contact lens for preventing bubble defects according to claim 3 , wherein the coating layer covers at least all optical surfaces on one side of the contact lens.


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