JP2724012C - - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for manufacturing an intraocular lens for correcting blue vision, and more particularly, to an intraocular lens for correcting blue vision occurring in aphakic eyes after cataract surgery. It relates to a manufacturing method. BACKGROUND ART In recent years, the number of senile cataract patients has been increasing with an increase in the aging population. Patients with aphakic eyes from which the lens has been removed by cataract surgery generally have glasses, contact lenses,
Visual acuity correction is performed using one of the intraocular lenses. In the case of correction by eyeglasses, the corrective lens becomes a thick convex lens and looks bad, and the retinal image becomes larger than the normal eye. It becomes large and the burden on the user is great. Therefore, in recent years, a contact lens that has excellent oxygen supply to the cornea and has a small burden on the cornea even when worn for a long time has been developed, and has become a very effective means for correcting vision in patients without aphakic eyes. In addition, an intraocular lens which does not need to be removed by being implanted in the eye has been developed and is becoming established in the market. Intraocular lenses have many advantages over the above-mentioned glasses and the like, and are expected to become more popular in the future. By the way, many patients with aphakic eyes after cataract surgery complain of photophobia or discomfort in color, and blue vision, in which an object appears bluish, is generally known. Blue vision is caused by the removal of the lens, which is originally yellow or yellowish-brown, so that blue light (yellowish-yellowish brown color) reaches the retina without being attenuated. It is a symptom that the object looks blue. Even when a conventional artificial intraocular lens is inserted into the eye, the eye with the posterior chamber lens made of polymethyl methacrylate (PMMA)
Since blue light reaches the retina without being attenuated, the color discrimination ability between blue and blue-violet is reduced as compared to the phakic eye. Therefore, there is a demand for an intraocular lens capable of correcting blue vision, and an intraocular lens containing an ultraviolet absorber has been commercialized for the purpose of approximating the light absorption characteristics inherent to the crystalline lens. However, ultraviolet absorbers have extremely low absorption in the visible region and can absorb ultraviolet light of 400 nm or less, which is considered to be a harmful wavelength, but cannot absorb visible blue light. Is incomplete. Therefore, if the intraocular lens is made to contain a large amount of an ultraviolet absorber to increase the light absorption in the visible region, the physical properties of the lens material often deteriorate, which is not preferable. Incidentally, a so-called prepolymer method is known as a method for producing this kind of intraocular lens containing an ultraviolet absorbent. In this prepolymer method, a monomer solution containing a monomer capable of forming a transparent lens material by polymerization, an ultraviolet absorber, and a polymerization initiator is introduced into a reaction vessel, and then heated at a predetermined temperature for a predetermined time to obtain a high-viscosity resin. After obtaining a prepolymer, and then filtering the prepolymer with a filter, for example, pouring the prepolymer into a cell formed by two glass plates and a gasket, and further heating at a predetermined temperature for a predetermined time to obtain a transparent lens material Things. In this prepolymer method, the prepolymer injected into the cell has a high viscosity so that it does not easily leak from the cell, and has a small shrinkage ratio in the process of obtaining a transparent lens material from the prepolymer, so that a transparent lens having a desired shape is obtained. It has the advantage that a material can be obtained, but on the other hand, (i) the operation is complicated because the polymerization is performed in two steps, and (ii) the control of the polymerization rate and viscosity of the prepolymer obtained in the first polymerization step It is difficult, for example, to increase the polymerization rate and, as a result, to increase the viscosity, it becomes difficult to carry out the filtration treatment performed before injecting the prepolymer into the cell. When using a 0.2 micron filter,
It is extremely difficult to filter the high-viscosity prepolymer). (Iii) When a crosslinkable monomer is used to impart hardness or the like to the obtained polymer, undesirable insoluble A polymer is produced, and in this case, not only the filtration process becomes difficult, but also an insoluble polymer is produced in the production process of the polymer after the filtration process, and the obtained polymer (intraocular lens material) becomes non-uniform. There are problems such as becoming. Therefore, an object of the present invention is to solve the drawbacks of conventional intraocular lenses containing an ultraviolet absorber and to effectively correct blue vision that occurs in aphakic eyes after cataract surgery. An object of the present invention is to provide a method for manufacturing a lens. Another object of the present invention is to provide a method for producing an intraocular lens for correcting blue vision, which can smoothly obtain an intraocular lens capable of effectively correcting the blue vision without performing a complicated operation. To provide. DISCLOSURE OF THE INVENTION As a result of studies to achieve the above object, the present inventors have found that a monomer solution containing a polymerizable monomer, a specific colorant, a polymerization initiator, and an ultraviolet absorber as shown below is formed into a mold. It has been found that an intraocular lens having light absorption characteristics similar to the light absorption characteristics of the human eye lens and effective for correcting blue vision can be obtained by the monomer cast polymerization method of injecting into a single step and polymerizing in one step. . In addition, it has been found that the monomer cast polymerization method is simpler in operation than the prepolymer method in which polymerization is performed in two steps, and that a uniform method for the obtained intraocular lens is also ensured. Accordingly, the present invention comprises at least one monomer capable of forming a transparent lens material by polymerization, only a yellow colorant as a colorant, a polymerization initiator, and an ultraviolet absorber.
The amount of the colorant is 0.01 to 0.03% (W / V) of the total monomer amount,
A method comprising: injecting a monomer solution in which the amount of an absorbent is 0.03 to 0.05% (W / V) of the total monomer amount into a mold, and then sealing and polymerizing the mold. The present invention relates to a method for producing an intraocular lens for correcting blue vision by a cast polymerization method. According to the present invention, an intraocular lens having excellent hardness, solvent resistance, YAG laser resistance, and the like can be obtained by further including a crosslinkable monomer in the monomer solution. Furthermore, according to the present invention, by selecting an azo-based polymerization initiator as the polymerization initiator, a chemically stable colorant which suppresses a remarkable tendency of the colorant to fade when a peroxide-based polymerization initiator is used is suppressed. A good intraocular lens is obtained.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1 to 8 are graphs showing light transmittance curves of an intraocular lens for correcting blue vision obtained in Reference Examples and Examples. FIG. 9 is a graph showing an example of a light transmittance curve of a human lens. FIG. 10 is a graph showing a light transmittance curve of the intraocular lens of the comparative example. BEST MODE FOR CARRYING OUT THE INVENTION In the method of manufacturing an intraocular lens for correcting blue vision according to the present invention, first, at least one monomer capable of forming a transparent lens material by polymerization, and a yellow colorant as a colorant Only , a monomer solution containing a polymerization initiator and an ultraviolet absorber is prepared in advance. Monomers that can form a transparent lens material by polymerization include (meth) acrylic acid and alkanols having 1 to 6 carbon atoms (methanol, ethanol, propanol,
(Meth) acrylate obtained from butanol, heptanol and hexanol) is preferably used. Here, “(meth) acrylic acid” means both acrylic acid and methacrylic acid. A particularly preferred (meth) acrylate is methyl methacrylate. However, the monomer used in the present invention is not limited to the above (meth) acrylic acid ester, and other monomers can be used as long as they can form a transparent lens material by polymerization. These monomers include (i) styrene, vinyl group-containing monomers such as vinyl acetate, (ii) itaconic acid, fumaric acid, alkyl esters of unsaturated carboxylic acids such as maleic acid, (iii) methacrylic acid, acrylic acid, Unsaturated carboxylic acids such as itaconic acid, fumaric acid, and maleic acid; (iv) fluorine-containing monomers such as fluoro (meth) acrylate; and (v) silicone-containing monomers. One type of monomer may be used, or two or more types may be used. When two or more monomers are used, they may be a mixture of monomers selected from (meth) acrylates or a mixture of (meth) acrylates and the above-mentioned other monomers. Monomer solution, containing only the yellow colorant as an essential component as a further colorant.
Examples of the yellow colorant include, but are not limited to, CI (Color Index) Solvent Yellow 16, CI Solvent Yellow 29, CI Solvent Yellow 33, CI Solvent Yellow 44, CI Solvent Yellow 56, CI Solvent Yellow 77, CI Solvent Yellow 93, CI
Disperse Yellow 3 and the like. One of these colorants may be used, or two or more of them may be used. The yellow colorant has a maximum absorption wavelength between 350 and 400 nm, enables absorption of visible blue light and ultraviolet light, and imparts a blue vision correction effect to the obtained intraocular lens. The monomer solution further contains a polymerization initiator as an essential component. As the polymerization initiator, various polymerization initiators such as an azo-based polymerization initiator and a peroxide-based polymerization initiator can be used, and it is particularly preferable to use an azo-based polymerization initiator. The reason is that (i) in the method for producing an intraocular lens for correcting blue vision by the monomer cast polymerization method of the present invention, when an azo-based polymerization initiator is used, compared with the case where a peroxide-based polymerization initiator is used. (For example, 0.4 wt% of benzoyl peroxide, which is a peroxide-based polymerization initiator, and 2,2 ', which is an azo-based polymerization initiator).
0.1% by weight of azobisisobutyronitrile is sufficient), and the decomposition products of the polymerization initiator remaining in the produced polymer can be reduced, so that a chemically stable intraocular lens can be obtained. Possible, (ii) peroxide-based polymerization initiator has a bleaching action, and may cause fading of a colorant coexisting in a monomer solution, whereas in the case of an azo-based polymerization initiator, This is because there are few such problems. Specific examples of the azo polymerization initiator include 1,1'-azobis (cyclohexane-
1-carbonitrile), 2,2'-azobisisobutyronitrile, 2,2'-azobis (2,4-dimethylvaleronitrile), 2,2'-azobis (4-methoxy-2,4-dimethyl Valeronitrile), dimethyl 2,2'-azobisisoformate, and the like, and the amount of addition is preferably 0.001 to 1.0% (W / W) of the total monomer amount. The reason is that if it is less than 0.001% (W / W), the polymerization is insufficient and the polymerization is not uniform, while if it exceeds 1.0% (W / W), there is a risk of foaming. is there. The monomer solution further contains an ultraviolet absorber as an essential component. When this ultraviolet absorber is used together with the above-mentioned coloring agent, the light absorption of 300 to 500 nm can be arbitrarily adjusted. Therefore, the type and concentration of the coloring agent are selected in accordance with the visible absorption characteristics of the human lens, and the UV absorbing agent compensates for the lack of absorption in the ultraviolet to further improve the light absorbing characteristics of the human lens. It is possible to get closer. In the present invention using an ultraviolet absorber together with a colorant, the amount of the colorant is 0.01 to 0.03% (W / V) of the total monomer amount, and the amount of the ultraviolet absorber is 0.1% of the total monomer amount. 03-0.05% (W / V). That is, in the conventional intraocular lens in which only the ultraviolet absorber is mixed, the ultraviolet absorber is used in an amount of 0.3 to 0.5.
% (W / V), it is not possible to draw a line close to the light absorption characteristic curve of the human eye lens, whereas in the intraocular lens obtained by the present invention, the total amount of the colorant and the ultraviolet absorber is lower than that of the conventional art. The purpose can be achieved with a small amount of 1/5 or less of the amount of the ultraviolet absorber in the intraocular lens. Examples of such an ultraviolet absorber include benzotriazole-based 2- (2'-hydroxy-5'-methylphenyl) benzotriazole [for example, Tinuvin P, manufactured by Ciba-Geigy] 2- (2'-hydroxy-5'-tert-) Butylphenyl) benzotriazole 2- (2'-hydroxy-3 ', 5'-di-tert-butylphenyl) benzotriazole 2- (2'-hydroxy-3'-tert-butyl-5'-methylphenyl)- 5
-Chlorobenzotriazole [for example, Tinuvin 326, manufactured by Ciba Geigy] 2- (2'-hydroxy-3 ', 5'-di-tert-butylphenyl) -5-chlorobenzotriazole 2- (2'-hydroxy-3'5,5'-di-tert-amylphenyl) benzotriazole 2- (2'-hydroxy-4'-octoxyphenyl) benzotriazole salicylate phenyl salicylate p-tert-butylphenyl salicylate p-octylphenyl salicylate benzophenone 2 2,4-dihydroxybenzophenone 2-hydroxy-4-methoxybenzophenone 2-hydroxy-4-octoxybenzophenone 2-hydroxy-4-dodecyloxybenzophenone 2,2'-dihydroxy-4-methoxybenzophenone 2,2'-dihydroxy 4,4'-dimethoxy benzophenone 2-hydroxy-4-methoxybenzophenone-5-sulfonic benzophenone cyanoacrylate 2-ethylhexyl 2-cyano-3,3'-diphenylacrylate Ethyl-2-cyano-3,3'-diphenylacrylate And the like. Further, the monomer solution contains a crosslinkable monomer as an optional component . The use of this crosslinkable monomer improves the hardness and solvent resistance of the obtained intraocular lens. In addition, secondary cataract may occur after implantation of the intraocular lens, YAG laser treatment is performed to prevent the progression of the secondary cataract, cracks occur in the lens when the YAG laser is erroneously irradiated to the lens, Eventually, lens destruction and the like may occur, but the intraocular lens obtained using the crosslinkable monomer is unlikely to cause cracks due to erroneous irradiation of the YAG laser, and the monomer may be eluted from the lens even after the YAG laser treatment. Almost no, it has excellent chemical stability. Specific examples of the crosslinkable monomer include di- or poly (meth) acrylates of diol or polyol (here, “(meth) acrylate” means both acrylate and methacrylate), for example, ethylene glycol dimethacrylate, triethylene glycol Dimethacrylate, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, and divinylbenzene, vinyl acrylate, vinyl methacrylate, allyl acrylate, allyl methacrylate, diallyl phthalate, diethylene glycol bisallyl carbonate, and the like. It is preferable that the amount is 0.2 to 10% (W / V) of the monomer amount. The reason is that if it is less than 0.2% (W / V), the effect of improving the hardness, solvent resistance, and YAG laser resistance of the obtained intraocular lens is not sufficient, and the amount of the monomer eluted by YAG laser irradiation increases. On the other hand, if it exceeds 10% (W / V), the workability gradually decreases. In the method for producing an intraocular lens for blue vision correction of the present invention, the above obtained, comprising a polymerization monomer, a colorant, a polymerization initiator, and an ultraviolet absorber as essential components,
If necessary, a monomer solution containing a crosslinkable monomer is preferably filtered through a filter and then poured into a mold. The reason why it is preferable to carry out a filtration treatment with a filter before injecting into a mold is that this can remove dust and remove bacteria. Unlike the high-viscosity prepolymer that is filtered by the prepolymer method, the monomer solution has a low viscosity. For example, even if a filter having fine pores having a pore size of 0.2 micron is used, the filtration process is performed smoothly. be able to. The mold into which the monomer solution is injected can be glass or metal, or a plastic test tube such as polypropylene, polyethylene, or Teflon that is chemically stable to the monomer used, or an intraocular lens shape of the same material as above Type. The obtained polymer can be cut to obtain an intraocular lens, and the obtained polymer can be melted and then injected or compression-molded to obtain an intraocular lens. The shape and size of the mold into which is injected are appropriately selected. In the method for producing the intraocular lens for correcting blue vision of the present invention, the mold into which the monomer solution has been injected is then sealed, and then polymerized to obtain a polymer. This polymerization is performed in a single step, unlike the above-mentioned prepolymer method, and the operation is simple. The polymerization is carried out by means such as heating, ultraviolet irradiation, etc., depending on the type of the monomer used. However, since a monomer which is polymerized by heating is usually used as a monomer for an intraocular lens, heat polymerization is generally used. The conditions of the heat polymerization are different depending on the type of the monomer and the polymerization initiator used and the amount of the polymerization initiator to be used, but usually a stepwise or continuous heating method is adopted, and in the case of the stepwise heating method, For example, at 30-60 ° C
After heating for 100 hours, 2 to 20 hours at 70 to 90 ° C., then 2 to 100 to 120 ° C.
By heating for 10 to 10 hours, the desired polymer is obtained. The obtained polymer is gradually cooled to 30 to 60 ° C. over 2 to 24 hours, and further allowed to cool to room temperature, and then taken out of the mold. The polymer removed from the mold is processed into an intraocular lens using conventional intraocular lens processing techniques. Hereinafter, the present invention will be further described with reference to Examples and Reference Examples. Reference Example 1 100 ml of methyl methacrylate (MMA) as a monomer capable of forming a transparent lens material by polymerization, and 0.015 g (0.015% (W / V) of the total monomer amount) of CI solvent as a yellow colorant Yellow 77 as a polymerization initiator,
0.1 g (about 0.1% (W / W) of the total monomer amount) of 2,2'-azobisisobutyronitrile (AIBN) was used, and these were mixed to obtain a monomer solution. This monomer solution was filtered through a membrane filter (pore size 0.2 μm), and the filtrate was placed in a Pyrex test tube (inner diameter 15 mm) using the filtrate as a polymerization mold.
0 ml was injected. Then, the test tube was sealed, heated in a 45 ° C water bath for 24 hours, and then heated in a hot air circulating dryer at 60 ° C for 5 hours, 80 ° C for 6 hours, 110 ° C for 6 hours, and then heated to 60 ° C. And slowly cooled to room temperature to obtain a bar made of polymethyl methacrylate (PMMA). The obtained bar was processed into a button-shaped material having a diameter of 8 mm and a thickness of 3 mm. The button-shaped material is turned and polished to a diameter of 6.5 mm and a center thickness of 1 mm.
. An intraocular lens of 0 mm and an intraocular equivalent principal point refractive power of +20 D was obtained. When the light transmittance curve of this intraocular lens was measured using an ultraviolet-visible spectrophotometer UV-240 manufactured by Shimadzu Corporation, as shown in FIG. 1, the intraocular lens showed absorption up to around 300 to 500 nm, Its absorption characteristics are close to the light absorption characteristics of the human lens (FIG. 9 shows an example of the light transmittance curve of the human lens), and it is clear that it is effective for correcting blue vision. . Reference Example 2 Same as Reference Example 1 except that CI Solvent Yellow 29 having 0.03% (W / V) of the total monomer amount was used instead of CI Solvent Yellow 77 used in Reference Example 1 as a yellow colorant. To obtain an intraocular lens having a diameter of 6.5 mmφ, a center thickness of 1.0 mm, and an intraocular equivalent principal point refractive power of +20 D. The results of measuring the light transmittance curve of the obtained intraocular lens in the same manner as in Reference Example 1 are shown in FIG. As shown in FIG. 2, this intraocular lens also exhibits absorption around 300 to 500 nm similarly to the intraocular lens of Reference Example 1, and its absorption characteristics are close to the light absorption characteristics of the human lens. It was found to be effective in correcting blue vision. Example 1 100 ml of methyl methacrylate (MMA) as a monomer capable of forming a transparent lens material by polymerization, and 0.015 g (0.015% (W / V) of the total monomer amount) of CI solvent as a yellow colorant Yellow 77 was used as an ultraviolet absorber, and 0.03 g (0.03% (W / V) of the total monomer amount) of Tinuvin P (manufactured by Ciba Geigy) was used as a polymerization initiator. 0.1 g (of the total monomer amount) was used as a polymerization initiator. About 0.1% (W / W)) of 2,2'-azobisisobutyronitrile (AIBN) was used, and these were mixed to obtain a monomer solution. This monomer solution was filtered through a membrane filter (pore size 0.2 μm), and the filtrate was placed in a Pyrex test tube (inner diameter 15 mm) using the filtrate as a polymerization mold.
0 ml was injected. Then, the test tube was sealed, heated in a 45 ° C water bath for 24 hours, and then heated in a hot air circulating dryer at 60 ° C for 5 hours, 80 ° C for 6 hours, 110 ° C for 6 hours, and then heated to 60 ° C. And slowly cooled to room temperature to obtain a bar made of polymethyl methacrylate (PMMA). The obtained bar was processed into a button-shaped material having a diameter of 8 mm and a thickness of 3 mm. The button-shaped material is turned and polished to a diameter of 6.5 mm and a center thickness of 1.
An intraocular lens of 0 mm and an intraocular equivalent principal point refractive power of +20 D was obtained. FIG. 3 shows the result of measuring the light transmittance curve of this intraocular lens in the same manner as in Reference Example 1. In the case of the intraocular lens of Reference Example 1 using only the yellow colorant without using the ultraviolet absorber, as shown in FIG. 1, slight light transmission was observed in the ultraviolet region (300 to 370 nm). In the case of the intraocular lens according to the present embodiment, it is possible to completely absorb the light beam in the ultraviolet region as apparent from FIG. Therefore, it became clear that the intraocular lens of this example had light absorption characteristics much closer to the light absorption characteristics of the human eye lens, and was particularly effective for correcting blue vision. As a comparative example corresponding to the prior art, only tinuvin P of 0.3% (W / V) of the total monomer amount was added as an ultraviolet absorber without using a yellow colorant.
An intraocular lens was obtained in the same manner as described above. FIG. 10 shows a light transmittance curve of this comparative intraocular lens containing a large amount of an ultraviolet absorbent. As is apparent from FIG. 10, it is more difficult for the comparative intraocular lens to approach the light transmittance curve of the human eye lens than in the case of Example 1 even if the ultraviolet absorbent is contained in an extremely large amount. Met. From these results, in the intraocular lens of Example 1, even if the total amount of the coloring agent and the ultraviolet absorber was extremely small, 3/20 of the amount of the ultraviolet absorber of the comparative intraocular lens,
It has been clarified that the light absorption characteristics of the human lens can be made closer to those of the comparative intraocular lens. Examples 2 to 5 The intraocular lenses of Examples 2 to 5 were obtained in the same manner as in Example 1 except that the following were used as the yellow colorant and the ultraviolet absorber. (Example 2) Yellow colorant: CI Solvent Yellow 0.03% (W / V) of total monomer amount Ultraviolet absorber: Tinuvin P (Ciba Geigy) 0.03% (W / V) of total monomer amount (Example 3) Yellow colorant: CI Solvent Yellow 16% of total monomer amount (W / V) 16 UV absorber: Tinuvin of 0.05% (W / V) of total monomer amount 326 (manufactured by Ciba Geigy) (Example 4) Yellow colorant: CI Solvent Yellow 93 containing 0.01% (W / V) of total monomer amount Ultraviolet absorber: 0.05% (W / V) of total monomer amount V) Tinuvin 326 (manufactured by Ciba Geigy) (Example 5) Yellow colorant: CI Solvent Yellow 56 at 0.01% (W / V) of total monomer amount UV absorber: 0.05 of total monomer amount % (W / V) of Tinuvin 326 (manufactured by Ciba Geigy) The results of measuring the light transmittance curves of the intraocular lenses Nos. 5 and 5 in the same manner as in Reference Example 1 are shown in FIGS. 4, 5, 6 and 7, respectively. The light transmittance curves of the intraocular lenses of Examples 2 to 5 shown in FIGS. 4 to 7 are similar to the light absorption characteristics of the human lens as in the case of the intraocular lens of Example 1, It proved to be particularly effective for correcting blue vision. Example 6 An intraocular lens was obtained using the same yellow colorant and ultraviolet absorber as in Example 4, but using different amounts of these additives from Example 4. The amount of the yellow colorant (CI Solvent Yellow 93) used was 0.03% (W / V) of the total monomer amount (0.01% (W / V) in Example 4), The amount of the agent (Tinuvin 326) added was 0.03% (W / V) of the total monomer amount (0.05% (W / V) in Example 4). FIG. 8 shows the result of measuring the light transmittance curve of the obtained intraocular lens. From FIG. 8, the light transmittance curve of the intraocular lens according to the present example can absorb more visible light rays of 400 to 500 nm than the intraocular lens according to the example 4, and the yellow colorant It has been clarified that by appropriately changing the amount of the ultraviolet absorber added, various blue-eye correction intraocular lenses having different light absorption characteristics can be obtained. This is extremely significant in view of the fact that the light absorption characteristics of the human eye lens vary with age. Example 7 100 ml of methyl methacrylate (MMA) was used as a monomer capable of forming a transparent lens material by polymerization, and 2 g (2% of the total monomer amount) was used as a crosslinking monomer.
(W / V)) ethylene glycol dimethacrylate (EDMA) as a yellow colorant, and 0.01 g (0.01% (W / V) of the total monomer amount (W / V)) of CI Solvent Yellow 93 as an ultraviolet absorber 0.05g (0.05% of total monomer (W / V)
) Of Tinuvin 326 (manufactured by Ciba Geigy) as a polymerization initiator in an amount of 0.1 g (about 0.1% (W / W) of the total monomer amount) of 2,2'-azobisisobutyronitrile (A
IBN), and these were mixed to obtain a monomer solution. This monomer solution was filtered through a membrane filter (pore size 0.2 μm), and the filtrate was placed in a Pyrex test tube (inner diameter 15 mm) using the filtrate as a polymerization mold.
0 ml was injected. Then, after sealing the test specimen, the mixture was heated in a water bath at 45 ° C. for 24 hours, and then heated at 60 ° C. for 5 hours, at 80 ° C. for 6 hours, at 110 ° C. for 6 hours, and then at 60 ° C. And slowly cooled to room temperature to obtain a bar mainly composed of polymethyl methacrylate (PMMA). The obtained bar was processed into a button-shaped material having a diameter of 8 mm and a thickness of 3 mm. This button-shaped material is turned and polished to 6.5 mm in diameter and 1.0 mm in center thickness.
And an intraocular lens having an intraocular converted principal point refractive power of + 20D. Next, the amount of the crosslinkable monomer was changed to 0.2% (W / V), 10.0% (W / V) of the total monomer amount.
, 15.0% (W / V), except that the amount of the crosslinkable monomer was 2% (W / V) to obtain three more intraocular lenses. The obtained four kinds of intraocular lenses had a light transmittance curve similar to the light transmittance curve of the human eye lens, and the effectiveness as an intraocular lens for correcting blue vision was confirmed. The hardness, solvent resistance, lens workability, Nd: YAG laser resistance, and elution of the monomer, colorant, and ultraviolet absorber by Nd: YAG laser irradiation were tested for these four types of intraocular lenses. The results are shown in Table 1 together with the results of the intraocular lens without the addition of the crosslinkable monomer (corresponding to the intraocular lens of Reference Example 1). As is clear from Table 1, when the crosslinkable monomer is added in the range of 0.2 to 15% (W / V), the hardness, solvent resistance, and Nd: Y are higher than when no crosslinkable monomer is added.
It was confirmed that the AG laser property was remarkably improved and the amount of the monomer eluted by Nd: YAG laser irradiation was significantly reduced. Also, if the amount of crosslinkable monomer added is 10.0% (W / V) or less,
It turned out to be satisfactory. The test methods for various properties shown in Table 1 are as follows. (1) Hardness: JIS K using a test piece consisting of a disk with a diameter of 15 mm and a thickness of 5 mm
Measured based on 7202. (2) Solvent resistance: 0.5 g of the pulverized sample was put in a stoppered Erlenmeyer flask, 50 ml of benzene was added, and the mixture was allowed to stand at room temperature for 5 days while stirring at predetermined intervals to check the dissolved state of the sample. Observed. In the evaluation, a sample insoluble was evaluated as having good solvent resistance, and a sample soluble was evaluated as having poor solvent resistance. (3) Lens workability: Observe the surface condition after lathing with a 40x magnifying glass, check the condition of small surface shavings and cutting marks. ○, poor ones are indicated by △. (4) Nd: YAG laser resistance: After irradiating the intraocular lens with an Nd: YAG laser with a power of 2 mJ (millijoule) while aiming at the rear surface of the lens, the change of the intraocular lens is enlarged. Observed using a mirror. The change of the intraocular lens after the irradiation of the Nd: YAG laser is evaluated by dividing it into pits and cracks. The pits are through holes formed in the lens and are unique to laser irradiation. The pits have little effect on the optical properties of the lens because the through holes themselves are very small. In contrast, a crack is not limited to the formation of a through-hole in a lens, but also causes a secondary modification of the material in the periphery of the through-hole. Optical properties are not often maintained. In addition, cracks have a large degree of physical damage to the lens, and may even lead to destruction of the lens. (5) Elution of monomers etc. by Nd: YAG laser irradiation: diameter 12 mmφ, thickness 1 m
A test piece consisting of a disc having a diameter of m was put together with 4 ml of purified water into a spectrophotometer cell having a volume of 5 ml, and Nd: YAG was applied to the surface of the test piece 100 times with a power of 10 mJ (millijoule).
The laser was irradiated. After the irradiation, the test piece was taken out, the absorbance at the maximum absorption wavelength (206 nm) of the monomer was measured with a spectrophotometer, and Nd was obtained from a calibration curve prepared in advance.
: Amount of monomer eluted into water by YAG laser irradiation [MMA conversion value (unit: μ
g)] was calculated. For the colorant and the ultraviolet absorber, the absorbance was measured at the maximum absorption wavelength (detection limit: 0.007 ppm). As described above, the present invention provides a method for manufacturing an intraocular lens for correcting blue vision, which is capable of effectively correcting blue vision occurring in aphakic eye patients after cataract surgery. Was done. Further, according to the present invention, there is provided a method for producing an intraocular lens for correcting blue vision, wherein an intraocular lens capable of effectively correcting the blue vision is smoothly obtained without performing a complicated operation. Was.

Claims (1)

Claims: 1. A composition comprising at least one monomer capable of forming a transparent lens material by polymerization, only a yellow colorant as a colorant, a polymerization initiator, and an ultraviolet absorber ,
The amount of the colorant is 0.01 to 0.03% (W / V) of the total monomer amount,
A monomer solution in which the amount of the agent is 0.03 to 0.05% (W / V) of the total monomer amount is injected into the mold, and the mold is sealed and polymerized. A method of manufacturing an intraocular lens for correcting blue vision by a legal method. 2. The method according to claim 1, wherein the polymerization initiator is an azo-based polymerization initiator. 3. The amount of the azo polymerization initiator is 0.001 to 1.0% (W
/ W). 4. A monomer capable of forming a transparent lens material by polymerization is (meth) acrylate , the polymerization initiator is an azo-based polymerization initiator, and the ultraviolet absorber is
The method according to claim 1 , which is a benzotriazole-based ultraviolet absorber . 5. The method according to claim 1, wherein the monomer solution further comprises a crosslinking monomer. 6. The method according to claim 5, wherein the amount of the crosslinking monomer is 0.02 to 10% (W / V) of the total amount of the monomers. 7. An intraocular lens for correcting blue vision produced by the method according to any one of claims 1 to 6.