JP2929626B2 - High oxygen permeability contact lens - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a highly oxygen-permeable contact lens obtained by copolymerizing a fumaric acid diester and a vinyl ester, and more particularly to a protein having excellent mechanical strength and protein. The present invention relates to a highly oxygen-permeable contact lens which is non-water-containing, has little adhesion of calcium, calcium and the like, has no fear of bacterial contamination, and can be worn continuously.

<Prior Art> Generally, there are two types of contact lenses, a hard contact lens and a soft contact lens, and it is known that each has excellent characteristics. Specifically, for example, a hard contact lens containing polymethyl (meth) acrylate as a main component was first developed, but there was a problem in terms of a feeling of wearing and the like, and then a soft contact lens was developed and has been up to the present. .

Recently, a contact lens having an oxygen permeability imparted by improving a hard type, for example, JP-A-56-39450
(Meth) acrylate and alkyl (meth) having a siloxane group in the side chain disclosed in JP-A-56-40324, etc.
Contact lenses made of copolymers with acrylates and copolymers containing fluoroalkyl (meth) acrylate as a main component disclosed in JP-A-57-51705 and JP-A-57-211119 have been put to practical use. I have.

These hard contact lenses are characterized by having excellent performance in terms of visual acuity correction effect, durability, ease of handling, machinability, and the like. However, for example, a contact lens containing polymethyl (meth) acrylate as a main component has poor hydrophilicity, so that the feeling of wearing is poor and the oxygen permeability coefficient (DK value) is 0.5 × 10 ⁻¹¹ cm ³ · cm / cm ² sec · It has a drawback of low Hg, causing damage to the cornea if worn for a long time. Furthermore, contact lenses containing a copolymer of (meth) acrylate and alkyl (meth) acrylate having a siloxane bond in a side chain as a main component and contact lenses containing a fluoroalkyl (meth) acrylate as a main component have an oxygen-permeable property. Is slightly improved, but the DK value is 1 × 10 ^-11 to 40 × 10 ^-11 ml · cm / cm ² · se
At present, c · Hg is not enough.

As a contact lens having high oxygen permeability, a contact lens having a three-dimensional crosslinked structure having a fumarate ester skeleton and a (meth) acrylic ester skeleton is disclosed in JP-A-61-176909. Contact lenses using two types of fumaric acid diesters are disclosed in JP-A-62-99720, JP-A-62-160419,
JP-A-62-176518, JP-A-62-212618, JP-A-63-176518
No. 32518. However, among the contact lenses having a fumarate ester skeleton, the former has a relatively high oxygen permeability coefficient (DK value) of about 60, which is relatively high. Since the polymerization reactivity is insufficient, a completely crosslinked polymer is not obtained, and the surface hardness of the obtained contact lens is relatively low, and the mechanical strength is low. On the other hand, in the latter contact lens, there is no problem with the DK value, but the copolymerizability of the fumarate esters depends largely on the structure of the ester alkyl group, and depending on the combination, the molecular weight of the obtained polymer is low, and the contact lens is There is a disadvantage that it becomes soft. Further, when an ester alkyl group uses a fumarate ester having a bulky substituent such as a tert-butyl group, a hard resin having heat resistance can be obtained, but the mechanical strength is insufficient, and the resin is bent or dropped. When it is used, it must be carefully taken care of when it is actually used.

On the other hand, as a soft contact lens, a hydrophilic water-containing contact lens obtained by copolymerizing methyl (meth) acrylate and 2-hydroxyethyl (meth) acrylate or N-vinylpyrrolidone,
BACKGROUND ART Non-water-containing soft contact lenses obtained by copolymerizing butyl methacrylate and butyl acrylate have been produced. For various reasons, soft contact lenses instead of hard contact lenses are used.

Such hydrous soft contact lenses having hydrophilic properties are characterized by being soft and comfortable to wear on the eyeball and relatively high in oxygen permeability, but have low mechanical strength and require careful handling. In addition, there are many problems such as deposition of proteins, lipids, inorganic substances, and the like, and bacteria are easily propagated. Further, in reality, oxygen permeability is not always sufficient for long-term wearing. For non-hydrous soft contact lenses, the DK value is 10 ~ 30 × 10 ^-11 m
Although it is l · cm / cm ² · sec · Hg and has relatively good oxygen permeability, it is unsuitable for long-term continuous wearing because of its low affinity for the eyeball.

<Problems to be Solved by the Invention> The present invention provides a high oxygen permeable hard contact that has excellent visual acuity correcting effect, has oxygen permeability that allows long-term continuous wearing, and is excellent in shape stability, stain resistance, and durability. It is to provide a lens.

<Means for Solving the Problems> According to the present invention, the following general formula (I) (In the formula, X and Y are the same or different groups and each include a branched alkyl group having 3 to 12 carbon atoms, a cycloalkyl group having 4 to 10 carbon atoms, and a carbon having a branched alkyl group having 3 to 12 carbon atoms. A cycloalkyl group having 4 to 10 carbon atoms, an alkyl group having 3 to 12 carbon atoms or an aryl group having a cycloalkyl group having 4 to 10 carbon atoms, or a group comprising a combination of the above substituents. A fumaric acid diester represented by the following formula (II): CH ₂ CHCH—O—OC—Z (II) wherein a part or all of the atoms may be substituted by a fluorine atom; , Z is an alkyl group having 1 to 12 carbon atoms, 4 to 10 carbon atoms.
A cycloalkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 1 to 12 carbon atoms, an alkyl group having 1 to 12 carbon atoms or an aryl group having a cycloalkyl group having 4 to 10 carbon atoms or the above-mentioned substitution A group consisting of a combination of groups is shown. A part or all of the hydrogen atoms of the alkyl group may be substituted with a fluorine atom), and a vinyl ester in an amount of 1 to 20 parts by weight of the vinyl ester to 100 parts by weight of the fumaric acid diester. A highly oxygen-permeable contact lens comprising a non-crosslinkable polymer obtained by copolymerization, wherein the molecular weight of the non-crosslinkable polymer is 300,000 or more in number average molecular weight.

 Hereinafter, the present invention will be described in more detail.

The high oxygen permeable contact lens of the present invention is a polymer having a specific molecular weight obtained by copolymerizing a specific fumaric acid diester and a specific vinyl ester.

In the present invention, the fumaric acid diester used as a polymer component can be represented by the following general formula (I): In the formula, X and Y are the same or different groups and each have a branched alkyl group having 3 to 12 carbon atoms, a cycloalkyl group having 4 to 10 carbon atoms, and a carbon number having a branched alkyl group having 3 to 12 carbon atoms. It represents a cycloalkyl group having 4 to 10 carbon atoms, an alkyl group having 3 to 12 carbon atoms or an aryl group having a cycloalkyl group having 4 to 10 carbon atoms, or a combination of the above substituents.
Further, a part or all of the hydrogen atoms of the alkyl group may be substituted with a fluorine atom. In this case, when the number of carbon atoms of the substituent is out of the range, the production is difficult. Examples of the fumaric acid diester represented by the general formula (I) include diisopropyl fumarate and disec-fumarate.
Butyl, diisobutyl fumarate, di-tert-butyl fumarate, di-tert-amyl fumarate, di (3-pentyl) fumarate, di (2,3-dimethyl-2-butyl) fumarate, -3-pentyl fumarate -Tert-amyl, di-fumarate (2,
3-dimethyl-2-butyl), 3-pentyl-tert-butyl fumarate, 3-pentyl-tert-amyl fumarate, 3-pentyl-2,3-dimethyl-2-butyl fumarate, fumaric acid Examples include fumaric acid diesters such as dicyclopentyl, dicyclohexyl fumarate, and di (4-tert-butyl-cyclohexyl) fumarate. Also, the two diester residues are different,
For example, isopropyl fumarate-sec-butyl, isopropyl isobutyl fumarate, isopropyl fumarate-tert
-Butyl, tert-butyl-4-methyl-2-fumarate
Pentyl, tert-butyl-fumarate-n-pentyl, tert-butyl-3-fumarate, tert-fumarate
-Butyl-isobutyl, cyclohexyl fumarate-tert
-Butyl, (tert-butyl) fumarate-cyclohexyl-tert-butyl, (tert-butyl) cyclohexyl-4-methyl-2-pentyl fumarate, and the like. Some or all of the hydrogen atoms of the alkyl groups of these various fumaric acid diesters may be substituted with fluorine atoms.Examples thereof include, for example, isopropyl fumarate-2,2,2-trifluoroethyl , Isopropyl fumarate-1,1,1-trifluoromethyl, tert-butyl fumarate-1,1,1,3,3,3-hexafluoro-2-
Pentyl, tert-butyl fumarate-1,1,1-trifluoromethyl, tert-butyl-2,2,2-trifluoroethyl fumarate, cyclohexyl fumarate-1,1,1,3,3, Three
-Hexafluoro-2-pentyl, -tert-butyl-cyclohexyl fumarate-1,1,1,1,3,3,3-hexafluoro-2-pentyl and the like. In order to prepare the diesters, for example, a method in which fumaric acid and a corresponding alcohol are subjected to a normal esterification reaction, maleic acid and a corresponding alcohol are subjected to esterification and cis
-Trans isomerization method or once reacting maleic anhydride and an equimolar alcohol to form a monoester,
Next, there is a method of synthesizing an asymmetric ester by reacting a second alcohol, etc., but any of them can be industrially synthesized without any problem.

In the present invention, the vinyl ester to be copolymerized with the fumaric acid diester, polymerization reactivity, chemical properties such as monomer persistence and various physical necessary when processing the resulting polymer into a contact lens, particularly Mechanical strength,
Monomers having bending strength, difficulty in breaking, and affinity for eyes, and capable of giving a high molecular weight without lowering high oxygen permeability which is a feature of the present invention. II).

CH ₂ CHCH—O—OC—Z (II) wherein Z is an alkyl group having 1 to 12 carbon atoms, and 4 to 10 carbon atoms.
A cycloalkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 1 to 12 carbon atoms, an alkyl group having 1 to 12 carbon atoms or an aryl group having a cycloalkyl group having 4 to 10 carbon atoms or the above-mentioned substitution A group consisting of a combination of groups is shown. A part or all of the hydrogen atoms of the alkyl group may be replaced by fluorine atoms. At this time, when the number of carbon atoms of the substituent is out of the range, the production is difficult. Examples of the vinyl ester represented by the general formula (II) include vinyl acetate, vinyl propionate, vinyl butanoate, vinyl butyrate, vinyl pivalate, vinyl 2,2-dimethylbutanoate, and vinyl 2,2-dimethylpentanoate. , 2-methyl-2-ethyl-vinyl butanoate, p-te
Rt-butyl vinyl benzoate and the like can be mentioned. The vinyl ester can be easily prepared by a method of transesterifying vinyl acetate with a corresponding organic acid in the presence of a suitable catalyst.

The polymer used in the contact lens of the present invention needs to have a number average molecular weight of 300,000 or more in order to obtain particularly excellent oxygen permeability and mechanical strength.

In the present invention, the mixing ratio of the fumaric acid diester, which is a polymer component, and the vinyl ester is in the range of 1 to 20 parts by weight of one or more vinyl esters with respect to 100 parts by weight of the fumaric acid diester. It is preferable to carry out the polymerization. In this case, when the content exceeds 20 parts by weight, the oxygen permeability of the obtained contact lens becomes extremely low, and furthermore, the heat resistance, mechanical strength,
Hardness and the like become insufficient, which is not preferable. If the amount is less than 1 part by weight, the molecular weight does not increase and the effect of modification by copolymerization cannot be expected. In addition, performance as a contact lens,
For example, the feeling of wearing, the mechanical strength, the cracking property, and the like are poor and not practical, which is not preferable.

In preparing the polymer used in the contact lens of the present invention, the fumaric acid diester and the vinyl ester can be easily synthesized by, for example, a generally used radical polymerization method. That is, a radical polymerization initiator, for example, an azo radical polymerization initiator such as azobisisobutyronitrile, azobiscyclohexylcarbonitrile, azobisvaleronitrile or benzoyl peroxide, tert-butyl hydroperoxide, cumene peroxide, The polymerization can be carried out using an organic peroxide-based radical polymerization initiator such as diacyl peroxide; an inorganic radical polymerization initiator such as ammonium persulfate and potassium persulfate; or a number of other radical polymerization initiator systems. However, in order to obtain a molecular weight of 300,000 or more in terms of the number average molecular weight of the obtained polymer, the polymerization is preferably performed at a polymerization temperature of 40 ° C. or lower and a polymerization time of 10 to 150 hours, and radicals are easily generated at such a low temperature. Polymerization initiator, for example, low-temperature decomposable peroxides such as diisopropyl peroxydicarbonate, di-2-ethylhexyl peroxydicarbonate; 2,
Low-temperature decomposable azo compounds such as 2'-azobis (4-methoxy-2,4-dimethylvaleronitrile); azobisisobutyronitrile, azobiscyclohexylcarbonitrile,
It is preferable to synthesize a polymer by performing photosensitization polymerization at a low temperature using azobisvaleronitrile or the like.

Also, when synthesizing a polymer, it is important to lower the polymerization temperature and increase the concentration of the copolymerized monomer in order to sufficiently increase the molecular weight, and it is also important to increase the concentration of the copolymerized monomer, and bulk polymerization or a polymerization system close to this is preferable. Further, it is preferable to use a polymerization method in which impurities are less mixed. The contact lens of the present invention has excellent oxygen permeability
The DK value is preferably from 20 to 150 × 10 ⁻¹¹ ml · cm / cm ² · sec · mmHg, particularly preferably 30 × 10 ⁻¹¹ ml · cm / cm ² · sec · mmHg or more. In this case less than ^{20 × 10 -11 ml · cm /} cm 2 · sec · mmHg,
Insufficient oxygen permeability for long-term continuous wearing, and
Those exceeding 150 × 10 ⁻¹¹ ml · cm / cm ² · sec · mmHg are not preferable because physical properties such as strength are deteriorated as contact lenses.

In preparing the contact lens of the present invention,
It can be obtained by a commonly used method.For example, after a monomer material containing a polymerization initiator is polymerized or copolymerized in a container such as a test tube, a round bar or a block is obtained, and then cut and polished. Either processing into a lens that matches the prescription by machining, etc., or injecting a monomer containing a polymerization initiator into the space formed by two molds and directly molding it into a contact lens by mold polymerization However, the contact lenses obtained by these methods have low performance such as heat resistance and mechanical strength, and it is difficult to completely react the monomers by polymerization.

Therefore, in order to prepare a contact lens in the present invention, for example, after low-temperature polymerization of monomers, reprecipitation purification and removal of low molecular weight components, or after extraction, a copolymer having a number average molecular weight of at least 300,000 or more is obtained. Once removed, a method of forming a contact lens is preferable,
The resulting contact lenses also have excellent performance.

The contact lens of the present invention is prepared by dissolving a copolymer having a number average molecular weight of 300,000 or more synthesized by the above method in a relatively low boiling organic solvent to form a concentrated polymer solution. The organic solvent is gradually evaporated on a glass mold formed into a desired shape to form a contact lens, or an appropriate container, for example, a Teflon-based or metal-based container, and the polymer solution is placed in the container. There is a method of forming a transparent thick resin plate by gradually evaporating an organic solvent and then forming a desired contact lens by processing. The contact lens thus prepared has the same high surface hardness, heat resistance, and mechanical strength as a conventional contact lens made of polymethyl methacrylate resin, and the oxygen permeability of the obtained contact lens is As with the silicon-based methacrylic resin, a new type of excellent contact lens can be obtained with less deposition of proteins and calcium.

It is also possible to add a coloring agent such as a dye or an additive such as an ultraviolet absorber to the raw material monomer to carry out polymerization.

In the present invention, the contact lens obtained by the above-mentioned preparation method can be subjected to an acid or alkali treatment or a low-temperature plasma treatment to perform a surface modification.
The feeling of wearing can also be improved by performing graft polymerization of a hydrophilic monomer by low-temperature plasma treatment or the like.

<Effect of the Invention> The contact lens of the present invention has a number average molecular weight of 30 obtained by copolymerizing a fumaric acid diester and a vinyl ester.
Made of more than 000 polymer, excellent mechanical strength,
It is excellent in physical performance such as heat resistance and high surface hardness, and it is possible to obtain a hard type with high oxygen permeability that can be worn continuously.
It has excellent performance that can prevent the deposition of proteins, lipids, and minerals, specifically, for example, calcium and the like on the surface, and improves the disadvantages of conventional contact lenses, such as preventing the penetration of water into the inside of the lens.

<Examples> Hereinafter, the present invention will be described in more detail with reference to Examples.
The present invention is not limited to these.

Example 1 A 1-liter four-necked flask was equipped with a stirrer, a cooling pipe, and a nitrogen inlet pipe, and was charged with polyvinyl alcohol (degree of saponification).
570 parts by weight of a 0.2 wt% aqueous solution of 95%) (trade name: "Gohsenol KH-17" manufactured by Nippon Gohsei Chemical Co., Ltd.), 5 parts by weight of a 1 wt% aqueous sodium dodecyl sulfate solution, and calcium carbonate
Add 30 parts by weight and raise the internal temperature to 35 ° C while introducing nitrogen
Kept. On the other hand, a uniform solution was prepared by mixing 95 parts by weight of di-tert-butyl fumarate, 5 parts by weight of vinyl acetate, and 60 parts by weight of purified benzene, and nitrogen was sufficiently introduced into the solution to prepare diisopropyl peroxydicarbonate. Add 1.5 parts by weight, mix quickly, purge with nitrogen, place in the 1 liter four-necked flask, and stir at 35 ° C.
For 50 hours to carry out suspension polymerization. After completion of the polymerization, the reaction solution was acidified with hydrochloric acid to dissolve calcium carbonate, and then filtered to remove a particulate polymer. The particles were sufficiently washed with warm water to remove polyvinyl alcohol. Further, the obtained polymer is placed in a large amount of methanol, heated to reflux and unreacted di-tert-butyl fumarate,
After extracting vinyl acetate, unreacted polymerization initiator, and benzene, repeating extraction of low molecular weight components with a mixed solvent of benzene / methanol = 1/1, and then drying under reduced pressure to obtain a number average molecular weight of 350,000 (by GPC method). Thus, a copolymer of standard polystyrene was obtained. Dissolve the obtained copolymer in benzene,
The solution was placed in a glass mold for contact lenses, and benzene was slowly evaporated to form a transparent contact lens chip. The oxygen permeability and physical properties of the obtained contact lens were measured by the following methods. Table 1 shows the composition and performance of the copolymer.

Oxygen permeability coefficient MODEL 2110 (Multirange Ana) manufactured by Xertex Corporation
Using a lyzer for Dissolved Oxygen), the DK value (90 × 10 ^-11 ml · cm / cm ² · sec.) was measured for a test piece having a diameter of 12.7 mm and a thickness of 0.2 mm in 0.9% physiological saline at 35 ° C. mmHg).

12.7mm diameter, thickness in 0.2% egg white lysozyme aqueous solution
A 0.2 mm test piece was immersed at 37 ° C. for 24 hours, and the amount of adhesion was determined from the change in absorbance at 280 nm.

Vickers hardness (HV) It was measured using a Terasawa MM-2 type ultra-micro hardness tester manufactured by Taiyo Tester Co., Ltd.

Cracking test A smooth circular test piece with a diameter of 10 mm and a thickness of 0.2 mm was prepared, a load was applied from the diametric direction, and gradually bent. The measurement was performed with the sample as ○.

Examples 2 to 10 The copolymers having the molecular weights shown in Table 1 were prepared in the same manner as in Example 1 except that the fumaric acid diester and vinyl ester monomers shown in Table 1 were copolymerized in the proportions shown in Table 1. Then, a contact lens chip was prepared and its performance was evaluated. Table 1 shows the results.

 However, the abbreviations shown in Table 1 are shown below.

Abbreviations: DtBF (di-tert-butyl fumarate), DsBF (di-sec-butyl fumarate), tB / cHF (tert-butyl fumarate / cyclohexyl), tB / F ₃ EF (tert-butyl fumarate /
2,2,2-trifluoroethyl), iP / tBF (fumaric acid isopropyl / tert- butyl), tB / F ₁₃ OF (fumaric acid tert-
Butyl / perfluorohexylethyl), cH / 3PF (cyclohexyl fumarate / 3-pentyl), iP / tBcHF (isopropyl / 4-tert-butyl-cyclohexyl fumarate),
DcHF (dicyclohexyl fumarate), VAc (vinyl acetate), VPiv (vinyl pivalate), VDMB (vinyl 2,2-dimethylbutanoate), VMEB (vinyl 2,2-methyl-ethylbutanoate), VDMAB (4-dimethyl Vinyl aminobenzoate), VDMP (vinyl 2,2-dimethylpentanoate), VPr
o (vinyl propionate).

Comparative Example 1 Di-tert-butyl fumarate (5 g), benzene (1.5 g), and benzoyl peroxide (0.05 g) were placed in a glass ampule and subjected to vacuum degassing under a high vacuum in a conventional manner, followed by sealing. The polymerization tube thus obtained was placed in a reactor equipped with a shaker set at 65 ° C., and polymerized for 30 hours. After the reaction is completed, the polymer is
Dissolved in 50 ml of benzene, poured into a large amount of methanol to precipitate the polymer produced, isolated by filtration, and dried under reduced pressure to obtain 4.6 g of di-tert-butyl fumarate homopolymer. Was. The molecular weight of this polymer measured by GPC was 92,000. This polymer was dissolved in benzene to prepare a contact lens chip in the same manner as in Example 1, and the performance was examined. Table 1 shows the results. In the contact lens of Comparative Example 1, there was no problem with the gas permeability (DK value = 160), but it was found that the mechanical strength was low, it was very fragile, and it was not practical.

Comparative Example 2 di-tert-butyl fumarate 5 g, vinyl acetate 2 g, benzene
Using 0.5 g, 2,2'-azobisisobutyronitrile 0.05 g
The same procedure as in Comparative Example 1 was carried out except that the polymerization was carried out at 60 ° C. for 40 hours, to obtain 5.3 g of a copolymer having a molecular weight of 180,000. The obtained copolymer was dissolved in benzene to prepare a contact lens chip in the same manner as in Example 1, and the performance was examined. Table 1 shows the results. The contact lens of Comparative Example 2 has no problem in mechanical strength and cracking property, but has gas permeability (DK
The value = 15) was low, indicating that a problem occurred.

Comparative Example 3 5 g of di-tert-butyl fumarate and bis (2,2,2
-Trifluoroethyl), 0.5 g, benzene 2 g, 2,2'-azobisisobutyronitrile 0.05 g, and polymerization was carried out in the same manner as in Comparative Example 1 except that polymerization was carried out at 60 ° C. for 60 hours.
4.8 g of the copolymer No. 00 was obtained. The obtained polymer was dissolved in chloroform to prepare a contact lens chip in the same manner as in Example 1, and the performance was examined. Table 1 shows the results. Although the contact lens of Comparative Example 3 had a considerably high gas permeability (DK value = 65) and no problem, it was found that the mechanical strength was low and it was very easily broken, so that there was a problem in practice.

Continuation of front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G02C 7/04

Claims (2)

(57) [Claims] 1. A compound represented by the following general formula (I) (In the formula, X and Y are the same or different groups and each include a branched alkyl group having 3 to 12 carbon atoms, a cycloalkyl group having 4 to 10 carbon atoms, and a carbon having a branched alkyl group having 3 to 12 carbon atoms. A cycloalkyl group having 4 to 10 carbon atoms, an alkyl group having 3 to 12 carbon atoms or an aryl group having a cycloalkyl group having 4 to 10 carbon atoms, or a group comprising a combination of the above substituents. A fumaric acid diester represented by the following formula (II): CH ₂ CHCH—O—OC—Z (II) wherein a part or all of the atoms may be substituted by a fluorine atom; , Z is an alkyl group having 1 to 12 carbon atoms, 4 to 10 carbon atoms.
A cycloalkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 1 to 12 carbon atoms, an alkyl group having 1 to 12 carbon atoms or an aryl group having a cycloalkyl group having 4 to 10 carbon atoms or the above-mentioned substitution A group consisting of a combination of groups is shown. A part or all of the hydrogen atoms of the alkyl group may be substituted with a fluorine atom), and a vinyl ester in an amount of 1 to 20 parts by weight of the vinyl ester to 100 parts by weight of the fumaric acid diester. A highly oxygen-permeable contact lens comprising a non-crosslinkable polymer obtained by copolymerization, wherein the non-crosslinkable polymer has a molecular weight of 300,000 or more in number average molecular weight. 2. The polymer is obtained by copolymerizing the fumaric acid diester and the vinyl ester at a ratio of 1 to 20 parts by weight of a vinyl ester with respect to 100 parts by weight of a fumaric acid diester. 2. The highly oxygen-permeable contact lens according to claim 1, wherein the component is removed to obtain a polymer composition having a number average molecular weight of 300,000 or more, which is a cured polymer.