JP2724012B2 - Manufacturing method of intraocular lens for blue vision correction - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for producing an intraocular lens for correcting blue vision,
More specifically, the present invention relates to a method for manufacturing an intraocular lens for correcting blue vision which occurs in aphakic eyes after cataract surgery.

BACKGROUND ART In recent years, the number of senile cataract patients has been increasing with an increase in the aging population. An aphakic eye patient whose lens has been removed by cataract surgery generally performs vision correction using any of eyeglasses, contact lenses, and 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.In particular, in the case of a monocular aphakic eye, unequal image vision occurs and fatigue of the optic nerve and cranial nerve is caused. 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 widespread 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 colored yellow or tan, and the blue light (yellow or yellowish tan) reaches the retina without being attenuated. The object looks blue, and even when a conventional artificial intraocular lens is inserted into the eye, polymethyl methacrylate (PM
Since the blue light reaches the retina without attenuating the posterior chamber lens made of MA), 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 for the purpose of approximating the light absorption characteristics inherent to the crystalline lens,
An intraocular lens containing an ultraviolet absorber has been commercialized. However, ultraviolet absorbers have extremely low absorption in the visible region and can absorb ultraviolet rays 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. This has the advantage that the 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 is 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 a 0.2 micron filter is used, it is extremely difficult to filter the above high viscosity prepolymer.) (Iii) The obtained polymer is required to have hardness and the like. When a crosslinkable monomer is used, an undesirable insoluble polymer is generated at the stage of producing the prepolymer, and in this case, not only the filtration treatment becomes difficult, but also the insoluble polymer is produced in the production process of the polymer after the filtration treatment. The resulting polymer (intraocular lens material) may be non-uniform.

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 The present inventors have studied to achieve the above object, and as a result, a monomer solution containing a polymerizable monomer, a specific colorant, a polymerization initiator, and an ultraviolet absorber as shown below has been 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 and polymerizing in one step. Further, according to the monomer cast polymerization method, compared to the prepolymer method in which polymerization is performed in two steps,
It has been found that the operation is simple and that the uniformity of the obtained intraocular lens is ensured.

Accordingly, the present invention provides a method in which a monomer solution containing at least one monomer capable of forming a transparent lens material by polymerization, a yellow colorant, a polymerization initiator, and an ultraviolet absorber is injected into a mold, and the mold is sealed. A process for producing an intraocular lens for correcting blue vision by a monomer cast polymerization method.

According to the present invention, the monomer solution further contains a crosslinkable monomer, so that hardness, solvent resistance, and
An intraocular lens excellent in YAG laser properties and the like can be obtained.

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 FIG. 1 to FIG. 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 for producing 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, a yellow colorant, A monomer solution containing an initiator and an ultraviolet absorber is prepared in advance.

Examples of the monomer capable of forming a transparent lens material by polymerization include (meth) acrylic acid ester obtained from (meth) acrylic acid and an alkanol having 1 to 6 carbon atoms (methanol, ethanol, propanol, butanol, heptanol, 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) vinyl group-containing monomers such as styrene and vinyl acetate, (ii) alkyl esters of unsaturated carboxylic acids such as itaconic acid, fumaric acid and maleic acid, (iii) methacrylic acid, acrylic acid, Unsaturated carboxylic acids such as itaconic acid, fumaric acid, and maleic acid; (iv) fluoro (meth)
Examples include fluorine-containing monomers such as acrylates, 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.

The monomer solution further contains a yellow colorant as an essential component. 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, in the method for producing an intraocular lens for correcting blue vision by the monomer cast polymerization method of the present invention, the use of an azo-based polymerization initiator in comparison with the case of using a peroxide-based polymerization initiator in the method for producing an intraocular lens for correcting blue vision (For example, azo-based polymerization initiator with respect to 0.4% by weight of benzoyl peroxide which is a peroxide-based polymerization initiator)
0.1% by weight of 2,2'-azobisisobutyronitrile may be used), and the decomposition of the polymerization initiator remaining in the produced polymer can be reduced, so that a chemically stable intraocular lens is obtained. (Ii) The peroxide-based polymerization initiator has a bleaching action and may cause fading of the colorant coexisting in the monomer solution, whereas the 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, and 2,2'-azobis (2,4-dimethyl Valeronitrile), 2,2'-azobis (4-methoxy-2,4-dimethylvaleronitrile), dimethyl 2,2'-azobisinbutyrate and the like, and the amount of addition is 0.001 to 1.0% of the total monomer amount ( W / W). The reason is that if the content 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.

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.
The amount of the UV absorber is 0.03-0.05 of the total monomer amount.
% (W / V). In other words, in the conventional intraocular lens in which only the ultraviolet absorbent is mixed, even if the ultraviolet absorbent is used in the range of 0.3 to 0.5% (W / V), a line close to the light absorption characteristic curve of the human lens cannot be drawn. In the intraocular lens obtained by the present invention, the object can be achieved with a total amount of the colorant and the ultraviolet absorber of 1/5 or less of the amount of the ultraviolet absorber in the conventional 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'-di-tert-amylphenyl) benzotriazole 2- (2'-hydroxy-4'-octoxyphenyl) benzotriazole salicylic acid phenyl salicylate p-tert-butylphenyl salicylate p- Octylphenyl salicylate benzophenone 2,4-dihydroxybenzophenone 2-hydroxy-4-methoxybenzophenone 2-hydroxy-4-octoxybenzophenone 2-hydroxy-4-dodecyloxybenzophenone 2,2'-dihydroxy-4-methoxybenzophenone 2, 2'-dihydro C-4,4'-Dimethoxybenzophenone 2-hydroxy-4-methoxy-5-sulfonebenzophenone cyanoacrylate 2-ethylhexyl-2-cyano-3,3'-diphenylacrylate ethyl-2-cyano-3,3'- And diphenyl acrylate.

Further, the monomer solution contains a crosslinkable monomer as an essential component. The use of this crosslinkable monomer improves the hardness and solvent resistance of the obtained intraocular lens. In addition, after the intraocular lens implantation, secondary cataract may occur, YAG laser treatment is performed to prevent the progression of the secondary cataract, cracks in the lens when the YAG laser is erroneously irradiated to the lens at that time, Eventually, lens destruction and the like may occur, but the intraocular lens obtained using the crosslinkable monomer is YA
Cracks hardly occur due to erroneous irradiation of G laser,
Further, the monomer hardly elutes from the lens even after the YAG laser treatment, and 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 other divinylbenzene, vinyl acrylate, vinyl methacrylate, allyl acrylate, allyl methacrylate,
Examples thereof include diallyl phthalate and diethylene glycol bisallyl carbonate, and the added amount is preferably 0.2 to 10% (W / V) of the total monomer amount. The reason is,
If the content 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. (W / V), the workability gradually decreases.

In the method for producing a blue-vision correcting intraocular lens of the present invention, the above obtained, containing a polymerization monomer, a colorant, a polymerization initiator, an ultraviolet absorber and an essential component, and optionally crosslinkable The monomer solution containing the monomer is poured into a mold, preferably after being filtered through a filter. 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 filtering the high viscosity prepolymer by the prepolymer method, the monomer solution has a low viscosity.For example, the filtration process can be smoothly performed using a filter having fine pores having a pore diameter of 0.2 μm. it can.

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.

In addition, since the obtained polymer can be cut to obtain an intraocular lens, and after the obtained polymer is melted, it can be obtained by injection or compression molding to obtain an intraocular lens.
The shape and size of the mold into which the monomer solution is injected are appropriately selected.

In the manufacturing method of the intraocular lens for blue vision correction of the present invention, after the mold in which the monomer solution is injected is then sealed,
Polymerize 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, 30-60 ° C
After heating for 2 to 100 hours at 70 to 90 ° C for 2 to 20 hours, then 1
By heating at 00 to 120 ° C. for 2 to 10 hours, the desired polymer is obtained. The obtained polymer is gradually cooled to 30 to 60 ° C. over 2 to 24 hours, further cooled 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) was used 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 (W / V)) was used as a yellow colorant.
CI Solvent Yellow 77, as a polymerization initiator, 0.1 g
2,2′-azobisisobutyronitrile (AIBN) (about 0.1% (W / W) of the total monomer amount) was used, and these were mixed to obtain a monomer solution.

This monomer solution is added to a membrane filter (pore size 0.2
Micron), 20 ml of the filtrate was injected into a Pyrex-type test tube (inner diameter 15 mm) used as a polymerization mold. The tube was then sealed and placed in a 45 ° C water bath for 24 hours.
After heating for 60 hours, at 80 ° C for 5 hours at 60 ° C in a hot air circulation dryer
After heating for 6 hours at 110 ° C. for 6 hours, the mixture was gradually cooled to 60 ° C. over 6 hours, and then allowed to cool 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. This button-shaped material was subjected to lathing and polishing to obtain an intraocular lens having a diameter of 6.5 mmφ, a center thickness of 1.0 mm, and an intraocular converted principal point refractive power of + 20D. The light transmittance curve of this intraocular lens was measured using a Shimadzu UV-Vis spectrophotometer.
When measured using UV-240, as shown in FIG. 1, this intraocular lens showed absorption around 300 to 500 nm, and its absorption characteristics were close to the light absorption characteristics of the human eye lens (see FIG. 1). An example of the light transmittance curve of the human lens is shown in FIG. 9), which proved to be effective in correcting blue vision.

Reference Example 2 CI solvent used in Reference Example 1 as a yellow colorant
Instead of Yellow 77, 0.03% (W / V) of the total monomer amount of C
The same procedure as in Reference Example 1 was carried out except that I Solvent Yellow 29 was used, to obtain an intraocular lens having a diameter of 6.5 mm, a center thickness of 1.0 mm, and an intraocular equivalent principal point refractive power of + 20D.

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 shows absorption up to 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 (W / V)) of a yellow colorant as a yellow colorant.
CI Solvent Yellow 77 is used as an ultraviolet absorber.
03 g (approximately 0.03% (W / V) of the total monomer content) of Tinuvin P
Using 0.1 g (about 0.1% (W / W) of the total monomer amount) of 2,2'-azobisisobutyronitrile (AIBN) as a polymerization initiator, and mixing them. As a result, a monomer solution was obtained.

This monomer solution is added to a membrane filter (pore size 0.2
Micron), 20 ml of the filtrate was injected into a Pyrex test tube (inner diameter 15 mm) used as a polymerization mold. The tube was then sealed and placed in a 45 ° C water bath for 24 hours.
After heating for 60 hours, at 80 ° C for 5 hours at 60 ° C in a hot air circulation dryer
After heating for 6 hours at 110 ° C. for 6 hours, the mixture was gradually cooled to 60 ° C. over 6 hours, and then allowed to cool 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. This button-shaped material was polished and polished to obtain an intraocular lens having a diameter of 6.5 mmφ, a center thickness of 1.0 mm, and an intraocular converted principal point power of + 20D.

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 a yellow colorant without using an 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, 0.3% of the total monomer amount was used as an ultraviolet absorber without using a yellow colorant.
An intraocular lens was obtained in the same manner as in Example 1 except that only tinuvin P (W / V) was added. Contains a large amount of ultraviolet absorbers,
FIG. 10 shows a light transmittance curve of this comparative intraocular lens.
As is clear from FIG. 10, even in the case of the comparative intraocular lens, even if the ultraviolet absorbent is contained in a remarkably large amount, it is more difficult to approach the light transmittance curve of the human eye lens than in the case of Example 1. 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 as 3/20 of the amount of the ultraviolet absorber in the comparative intraocular lens, It has been clarified that it is possible to approach the light absorption characteristics of the human eye lens more than the 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 29 of 0.03% (W / V) of the total amount of monomers UV absorber: Tinuvin P (manufactured by Ciba Geigy) of 0.03% (W / V) of the total amount of monomers Example 3) Yellow colorant: CI Solvent Yellow 16 containing 0.01% (W / V) of total monomer amount UV absorber: Tinuvin 326 (manufactured by Ciba Geigy) containing 0.05% (W / V) of total monomer amount (Example 4) Yellow colorant: CI Solvent Yellow of 0.01% (W / V) of total monomer amount 93 UV absorber: Tinuvin 326 (manufactured by Ciba Geigy) of 0.05% (W / V) of total monomer amount (Example 5) Yellow Coloring agent: CI Solvent Yellow 56 having 0.01% (W / V) of the total monomer amount Ultraviolet absorber: Tinuvin 326 (manufactured by Ciba Geigy) having 0.05% (W / V) of the total monomer amount Examples 2 and 3 obtained The light transmittance curves of the intraocular lenses of Examples 4, 4 and 5 were measured in the same manner as in Reference Example 1. Results respectively shown in 4, 5, 6 and 7 FIG.

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 is 0.03% (W / V) of the total monomer amount
(0.01% (W / V) in Example 4), and the amount of the ultraviolet absorber (Tinuvin 326) added was 0.0% of the total monomer amount.
3% (W / V) (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 of the present embodiment is 400 to 5 compared to the intraocular lens of the fourth embodiment.
It is possible to absorb more visible light rays of 00 nm more, and by appropriately changing the addition amount of the yellow colorant and the ultraviolet light absorber, various intraocular lenses for correcting blue vision having different light absorption characteristics can be obtained. It became clear that it could be done. 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% (W / V) of ethylene glycol dimethacrylate (EDMA) of the total monomer amount) was used as a crosslinking monomer. As a yellow colorant, 0.01 g (0.01% (W / V) of the total monomer amount) of CI
Solvent Yellow 93, 0.05g as UV absorber
As a polymerization initiator, 0.1 g (about 0.1% (W / W) of 2,2′-) of tinuvin 326 (manufactured by Ciba-Geigy) containing 0.05% (W / V of the total monomer) was used as a polymerization initiator. Azobisisobutyronitrile (AIBN) was used and mixed together to obtain a monomer solution.

This monomer solution is added to a membrane filter (pore size 0.2
Micron), 20 ml of the filtrate was injected into a Pyrex test tube (inner diameter 15 mm) used as a polymerization mold. The tube was then sealed and placed in a 45 ° C water bath for 24 hours.
After heating for 60 hours, at 80 ° C for 5 hours at 60 ° C in a hot air circulation dryer
After heating for 6 hours at 110 ° C. for 6 hours, the resultant was gradually cooled to 60 ° C. over 6 hours, and then allowed to cool 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. The button-shaped material was turned and polished 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 + 20D.

Next, the amount of the cross-linkable monomer was changed to 0.2% (W
/ V), 10.0% (W / V), and 15.0% (W / V) except that the amount of the crosslinkable monomer was 2% (W / V). Intraocular lens was obtained.

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 monomers, colorants, and ultraviolet absorbers by Nd: YAG laser irradiation were also 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 evident from Table 1, the crosslinkable monomer was 0.2 to 1
When added in the range of 5% (W / V), the hardness, solvent resistance and Nd: YAG laser resistance are remarkably improved as compared with the case where no crosslinkable monomer is added, and the amount of monomer eluted by Nd: YAG laser irradiation Was significantly reduced.

In addition, the amount of crosslinkable monomer added is 10.0% for lens processing.
(W / V) When it was below, it became clear that it was satisfactory.

The test methods for various properties shown in Table 1 are as follows.

(1) Hardness: Measured based on JIS K 7202 using a test piece consisting of a disk having a diameter of 15 mmφ and a thickness of 5 mm.

(2) Solvent resistance: 0.5 g of the crushed sample is placed in a stoppered Erlenmeyer flask, 50 ml of benzene is added, and then left at room temperature for 5 days while stirring at predetermined intervals to observe the dissolution state of the sample. did. 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 state of the surface after lathing with a magnifier of 40x, and check the condition of small surface shavings and cutting marks. ，, poor ones are indicated by △.

(4) Nd: YAG laser resistance: Power for intraocular lens
After irradiating a 2 mJ (millijoule) Nd: YAG laser aiming at the rear surface of the lens, changes in the intraocular lens were observed using a magnifying glass. 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 and the like by Nd: YAG laser irradiation: A test piece consisting of a disc having a diameter of 12 mm and a thickness of 1 mm was put into a 5 ml volume spectrophotometer cell together with 4 ml of purified water, and the surface of the test piece was 10 mJ Nd: YAG laser irradiation was performed 100 times at a power of (millijoules). After irradiation, remove the test piece, measure the absorbance of the monomer at the maximum absorption wavelength (206 nm) with a spectrophotometer, and determine the amount of monomer eluted in water by Nd: YAG laser irradiation [MMA conversion value] from a calibration curve created in advance. (unit:
μg)] was calculated.

For the colorant and the ultraviolet absorber, the absorbance was measured at the respective maximum absorption wavelengths (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 can be obtained smoothly without performing a complicated operation. Was.

Claims (8)

(57) [Claims] A monomer solution containing at least one monomer capable of forming a transparent lens material by polymerization, a yellow colorant, a polymerization initiator, and an ultraviolet absorber is injected into a mold, and the mold is sealed. A method for producing an intraocular lens for correcting blue vision by a monomer cast polymerization method, which comprises a step of polymerizing by means of a monomer cast polymerization method. 2. The amount of the colorant is 0.01 to 0.03% of the total monomer amount.
(W / V), and the amount of the ultraviolet absorber is 0.0% of the total monomer amount.
The method according to claim 1, wherein the amount is 3 to 0.05% (W / V). 3. The method according to claim 1, wherein the polymerization initiator is an azo polymerization initiator. 4. The amount of the azo-based polymerization initiator is 0.1% of the total monomer amount.
4. The method according to claim 3, wherein the amount is 001 to 1.0% (W / W). 5. The monomer capable of forming a transparent lens material by polymerization comprises (meth) acrylic acid ester, vinyl group-containing monomer, unsaturated carboxylic acid alkyl ester, unsaturated carboxylic acid, fluorine-containing monomer and silicone-containing monomer. The method according to claim 1, wherein the method is selected from the group. 6. The method according to claim 1, wherein the monomer solution further comprises a crosslinking monomer. 7. The amount of the crosslinkable monomer is 0.02 of the total monomer amount.
7. The method according to claim 6, wherein the method is 1010% (W / V). 8. An intraocular lens for correcting blue vision, produced by the method according to any one of claims 1 to 7.