JP2002182167A - Plastic molding and contact lens consisting of it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a plastic molding excellent in the balance of every kind of performance such as high oxygen permeability, low elastic modulus and high moisture content, and to provide a plastic molding for a contact lens or the like. SOLUTION: As for this plastic molding, an oxygen permeation coefficiency is >=60×10-11 (cm2/sec) [mlO2/(ml.hPa)] and the elastic modulus is 275 to 830 kPa.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plastic molded article having both high oxygen permeability, low elastic modulus and high water content, and is particularly suitable for ophthalmic lenses such as contact lenses, intraocular lenses and artificial cornea. Used for

[0002]

2. Description of the Related Art In recent years, plastic molded articles have been proposed for various uses. Among them, various plastic molded articles containing silicon or fluorine have been proposed for contact lenses because of their good oxygen permeability. However,
Plastic molded articles containing silicon and fluorine certainly have high oxygen permeability, but when applied to soft contact lenses, a low elastic modulus is particularly desired because of its high elasticity and poor wearing feeling. As a material of a plastic molded product having both high oxygen permeability and high water content, a macromer type having a silicone polymer segment, a hydrophilic polymer segment (eg, polyethylene glycol) and a polymerizable group is used. (US Pat. No. 5,760,
No. 100, U.S. Pat. No. 5,776,999). However, such a macromer-type material has a problem that purification is difficult and the quality is not stable because of its high molecular weight. On the other hand, as a monomer having a relatively low molecular weight which is not a macromer, tris (trimethylsiloxy) silylpropyl methacrylate is widely used as an ophthalmic lens material. (JP-A-60-142324)
JP, JP-A-54-24047). The polymer obtained by polymerizing tris (trimethylsiloxy) silylpropyl methacrylate certainly has high oxygen permeability, but has a relatively high elastic modulus and is not optimal for use in soft contact lenses.

On the other hand, for example, JP-A-56-39450 and JP-B-56-40324 describe a monomer represented by the following formula (M1).

[0004]

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[0005] A polymer obtained by polymerizing this monomer has characteristics of having a relatively high oxygen permeability and a relatively low elastic modulus. However, in recent years, as a polymer for an ophthalmic lens, an even higher oxygen permeability has been required to enable continuous wearing for a longer time, and an ophthalmic lens obtained from a monomer of the formula (M1) has been required. The oxygen permeability of the application polymer was not always sufficient.

[0006]

DISCLOSURE OF THE INVENTION The present inventors have made intensive studies to solve the above-mentioned problems and have an object to provide plastic molded articles having high oxygen permeability, high water content and low elastic modulus.

[0007]

The present invention has the following arrangement to achieve the above object. “(1) Oxygen permeability coefficient is 60 × 10 ⁻¹¹ (cm ² / sec)
c) A plastic molded article having a modulus of not less than [mlO ₂ / (ml · hPa)] and an elastic modulus of not more than 275 to 830 kPa, and (2) containing silicon and / or fluorine atoms. The plastic molded article according to claim 1, wherein (3) the water content is 15% or more and 60% or less, the plastic molded article according to claim 1 or 2, and (4) any of claims 1 to 3. A contact lens comprising a plastic molded product according to item 1. "

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The plastic molded articles of the present invention include homopolymers of various monomers described below, copolymers of these monomers and other monomers, and polymers containing silicon in the main chain and / or side chains. A molded article mainly composed of a polymer (for example, a polymer containing an organic silane group such as a siloxane bond or a trimethylsilyl group) or a polymer containing a carbon or fluorine bond. Specific examples of monomers for obtaining such a polymer include tris (trimethylsiloxy) silylpropyl (meth) acrylate, polydimethylsiloxane having double bonds at both ends, silicone-containing (meth) acrylate and fluorine-containing (meth) acrylate. Is mentioned. Examples of the plastic molded article of the present invention include homopolymers using these monomers, and copolymers of these monomers and other monomers. Monomers that can be copolymerized include monofunctional monomers such as (meth) acrylic monomers, aromatic vinyl monomers, and heterocyclic vinyl monomers, or bifunctional, trifunctional, tetrafunctional (meth) acrylates, aromatic divinyl monomers, Examples include polyfunctional monomers such as aromatic diaryl monomers. Specific examples of the monofunctional monomer include alkyl (meth) acrylates such as methyl (meth) acrylate and ethyl (meth) acrylate, carboxylic acids such as (meth) acrylic acid, and cycloalkyl (meta) such as cyclohexyl (meth) acrylate. ) Acrylates, halogenated alkyl (meth) acrylates such as trifluoroethyl (meth) acrylate, hexafluoroisopropyl (meth) acrylate, 2
Hydroxyalkyl (meth) acrylates having a hydroxyl group, such as -hydroxyethyl (meth) acrylate and 2,3-dihydroxypropyl (meth) acrylate;
Diacrylamides such as N, N-dimethylacrylamide and N, N-diethylacrylamide; alkyl (meth) acrylates having a siloxanyl group such as tris (trimethylsiloxy) silylpropyl (meth) acrylate; and aromatics such as styrene and vinylpyridine. And heterocyclic vinyl monomers such as N-vinylpyrrolidone. Specific examples of the bifunctional monomer include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, bisphenol A di (meth) acrylate, ethylene oxide-added dibisphenol A (meth) acrylate and its urethane modified product, propylene glycol ( Meta)
Acrylate, glycerol di (meth) acrylate,
Neopentyl glycol (meth) acrylate and the like. Specific examples of the trifunctional monomer include trimethylolpropane tri (meth) acrylate and ethylene oxide-added trimethylolpropane tri (meth) acrylate. Specific examples of the tetrafunctional monomer include tetramethylolmethanetetra (meth) acrylate. Specific examples of the aromatic divinyl monomer include divinylbenzene and the like, and specific examples of the aromatic diaryl monomer include diaryl phthalate. Specific examples of other polyfunctional monomers include bismaleimide and allyl (meth) acrylate. Depending on the copolymerization ratio of these monomers, the plastic molded article used in the present invention may be a hydrogel containing water, a rubbery polymer containing no water, or a hard polymer containing no or low water content. There may be.

The plastic molded article of the present invention may be transparent or opaque.
Alternatively, a plastic molded article containing a fluorine atom is preferably applied to an optical material or the like because of its excellent oxygen permeability. In this case, a plastic article having transparency is preferably used. In the polymer constituting the plastic molded article of the present invention, the content of the polymer containing silicon and / or fluorine atoms is preferably 5% by weight or more in that the balance between oxygen permeability and mechanical properties can be maintained. ,
It is more preferably at least 30% by weight. In addition, a well-known method can be used as a polymerization method. Further, the plastic molded article of the present invention may contain an ultraviolet absorber, a dye, a colorant, and the like. When obtaining the plastic molded article of the present invention, it is preferable to add a thermal polymerization initiator represented by a peroxide or an azo compound, or a photopolymerization initiator in order to facilitate polymerization. In the case of performing the thermal polymerization, a material having an optimum decomposition characteristic for a desired reaction temperature is selected and used. Generally, the 10-hour half-life temperature is 40-120.
C. Peroxide initiators and azo initiators are preferred. Examples of the photopolymerization initiator include carbonyl compounds, peroxides, azo compounds, sulfur compounds, halogen compounds and metal salts. These polymerization initiators are used alone or as a mixture, and are used in an amount up to about 1% by weight. When obtaining the plastic molded article of the present invention, a polymerization solvent can be used. As the solvent,
Various organic and inorganic solvents are applicable and are not particularly limited, but include, for example, water, methanol, ethanol, propanol, 2-propanol, butanol, various alcohol solvents such as tert-butanol, benzene, toluene, xylene and the like. Various aromatic hydrocarbon solvents, various aliphatic hydrocarbon solvents such as hexane, heptane, octane, decane, petroleum ether, kerosene, ligroin, paraffin, various ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and ethyl acetate , Butyl acetate, methyl benzoate, dioctyl phthalate and other ester solvents, diethyl ether, tetrahydrofuran, dioxane, ethylene glycol dialkyl ether, diethylene glycol dialkyl ether, triethylene glycol Various glycol ether-based solvents such as dialkyl ether, tetraethylene glycol dialkyl ether, and polyethylene glycol dialkyl ether are listed, and these can be used alone or in combination.

The plastic molded article of the present invention is, for example,
It can be manufactured by the following method.

That is, the polymer is once formed into a round bar or a plate shape and processed into a desired shape by cutting or the like, or a known method such as mold polymerization or spin cast polymerization can be used. . Further, when forming into a fiber, a film, or the like, the polymer can be melted or dissolved with a solvent, and then spun and extruded. As an example, a case where the plastic molded article of the present invention is obtained by a mold polymerization method will be described below. The monomer mixture of the monomer composition and the polymerization initiator is filled into two voids having a predetermined shape. Then, photopolymerization or thermal polymerization is performed to shape the mold. The mold is made of resin, glass, ceramics, metal, or the like. In the case of photopolymerization, an optically transparent material is used, and usually, resin or glass is used. In the case of manufacturing a plastic molded article, in many cases, a void is formed by two opposing molds, and the void is filled with the monomer mixture. However, depending on the shape of the mold and the properties of the monomer mixture, the plastic is formed. A gasket having the purpose of giving the molded article a certain thickness and preventing leakage of the filled monomer mixture may be used in combination. The mold in which the voids are filled with the monomer mixture is subsequently irradiated with an actinic ray such as ultraviolet light, or is heated in an oven or a liquid tank to be polymerized. There may be a method of using both polymerization methods in which thermal polymerization is performed after photopolymerization, or conversely, photopolymerization is performed after thermal polymerization. In the case of photopolymerization, for example, light containing a large amount of ultraviolet light using a mercury lamp or insect lamp as a light source is generally irradiated for a short time, and usually within one hour. In the case of performing thermal polymerization, the condition of gradually increasing the temperature from around room temperature to raising the temperature to 60 to 200 ° C. over several hours to several tens of hours maintains the optical uniformity and quality of the plastic molded product. It is suitable for improving the reproducibility.

The oxygen permeability of the plastic molded article of the present invention is measured by an electrode method. Oxygen permeability coefficient is 60 × 1
0 ^-11 (cm ² / sec) [mlO ₂ / (ml · hP
a)], when the plastic molded article of the present invention is applied to a contact lens, it becomes difficult to sufficiently supply oxygen necessary for the cornea from the corneal surface through the lens, and the wearer has been continuously worn for a long time. In this case, the physiological burden on the cornea tends to increase. The elastic modulus is 275-8
The pressure is preferably 30 kPa, and if it is smaller than this value, it is too soft and the shape retention is poor, and handling is difficult. If it is large, the wearing feeling as a contact lens is poor, and more preferably 345 to 620 kPa. The water content is preferably from 15 to 60%, and more preferably from 20 to 50%. By adjusting the water content to 15% or more, when applied as a soft contact lens, the movement in the eyes becomes smooth and continuous wearing becomes easy. If the water content exceeds 60%, the oxygen permeability is undesirably reduced.

The plastic molded article of the present invention can be subjected to a surface modification treatment by various methods, and can improve the surface wettability. As a specific surface modification treatment method for a plastic molded article, a known physical technique and a chemical technique can be used. When the plastic molded article is a hydrogel, treatment with a high molecular weight acid or base is particularly effective.

Preferred embodiments of the plastic molded article of the present invention include lenses, fibers, films and the like. Particularly, from the viewpoint of good optical properties, high oxygen permeability, good water wettability and mechanical properties. It is suitably used for optical articles such as contact lenses, intraocular lenses, and plastic lenses.

[0015]

The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

Each measurement and evaluation was carried out by the following methods. 1. Water content After the plastic molded article was hydrated, the water content (%) of the polymer was measured by the following formula.

Water content (%) = (W−WO) / W * 100 (W is the weight (g) of the plastic molded article after the hydration treatment, and WO is the weight of the plastic molded article in a dry state. (G)). 2. Dynamic Contact Angle Using a plastic molded product having a size of 5 mm × 10 mm × 0.1 mm, a dynamic contact angle at the time of advance with respect to a borate buffer (pH 7.1 to 7.3) was measured. The immersion speed is 0.1 mm /
sec, the immersion depth was 7 mm. The dynamic contact angle of the present invention is an evaluation of surface tension and contact angle based on the principle of the Wilhelmy method (Fiber Polymer Materials Laboratory Report No. 16
No. 7, Special Issue, "Study on Synthesis and Function of Thermosensitive Polymer", pp. 51-52). 3. Water wettability The plastic molded product is diluted with borate buffer (boric acid, sodium borate, sodium chloride and disodium ethylenediaminetetraacetate in purified water at pH 7.1 to pH 7.1).
After being immersed in 7.3) overnight, it was pulled up, the surface appearance was visually observed, and evaluated according to the following criteria.

A: The surface of the plastic molded product is uniformly wet.

：: More than half of the surface area of the plastic molded product is uniformly wet.

Δ: Wetting of more than half of the surface area of the plastic molded product is non-uniform.

×: The surface of the plastic molded product is hardly wet. 4. Mechanical Properties As a sample, a plastic molded product having a size of 15 mm × 10 mm × 0.1 mm was used, and the elastic modulus was measured using Tensilon RTM-100 manufactured by Toyo Baldwin Co., Ltd. Pull at a speed of 100 mm / min,
The distance between the grips was 5 mm. 5. Oxygen Permeability As a sample, a plastic molded product having a size of 15 mmφ was used, and the oxygen transmission coefficient was measured in water at 35 ° C. using a Kakenhi type film oxygen permeability meter manufactured by Rika Seiki Kogyo Co., Ltd. In addition, the thickness of the sample was adjusted by laminating a plurality of sheets as necessary. Example 1 Tris (trimethylsiloxy) silylpropyl acrylate 50 parts by weight, compound (M1) 25 parts by weight, N-vinylformamide 25 parts by weight, acrylic acid 1 part by weight, vinyl acrylate 0.2 part by weight, triethylene glycol After uniformly mixing 1 part by weight of dimethacrylate and 20 parts by weight of ethylene glycol diacetate and adding 0.5 part by weight of "Darocur 1173" (manufactured by CIBA) as a polymerization initiator, the monomer mixture was placed under an argon atmosphere. Degassed. It was injected between plastic molds in a glove box under a nitrogen atmosphere and sealed. Light irradiation using insect lamp with (illuminance 1 mW / cm ^2, 25 min), the polymerization was carried out. Then, each mold is immersed in isopropyl alcohol at 40 ° C./30 minutes, and further at 60 ° C./60 minutes.
After immersing for a minute, the mold was released to obtain a plastic molded article to be treated. Thereafter, the remaining monomer was extracted at 60 ° C. for 16 hours. Thereafter, the plastic molded article to be treated is washed twice with isopropyl alcohol, and then immersed in isopropyl alcohol / purified water = 50/50 (parts by weight) for 30 minutes, and then isopropyl alcohol / purified water = 25/50.
75 (parts by weight) for 30 minutes.
After immersion for a while, isopropyl alcohol was completely removed from the plastic molded product to obtain a plastic molded product to be treated. The plastic molded article to be treated is 0.25
It was immersed in an N-NaOH aqueous solution at 23 ° C./24 hours. Thereafter, the plastic molded product is sufficiently washed with purified water, and then a borate buffer (pH 7.1 to 7.3) in a vial bottle.
And the vial was sealed. The vial was placed in an autoclave and subjected to boiling at 120 ° C. for 120 minutes. After cooling, the plastic molded product was taken out of the vial and immersed in a borate buffer (pH 7.1 to 7.3). The moisture content of this plastic molded product is 35%,
The advancing contact angle in borate buffer was 48 °. The water wettability was ◎. Further, the mechanical properties are as follows:
It was 45 kPa. Furthermore, the oxygen permeability coefficient is 90 ×
10 ^-11 (cm ² / sec) [mlO ₂ / (ml · hP
a)]. Example 2 Tris (trimethylsiloxy) silylpropyl acrylate 56.25 parts by weight, Compound 1 of (M2) shown below
8.75 parts by weight, 25 parts by weight of N-vinylformamide,
Polyethylene glycol dimethacrylate (MW: 77
1) 1 part by weight and 20 parts by weight of diethylene glycol dimethyl ether were uniformly mixed, and 0.5 part by weight of "Darocur 1173" (manufactured by CIBA) was added as a polymerization initiator. Then, the monomer mixture was degassed under an argon atmosphere. did. It was injected between plastic molds in a glove box under a nitrogen atmosphere and sealed. Polymerization was performed by irradiating light (illuminance: 1 mW / cm ² , 10 minutes) using a trap lamp. Thereafter, the mold is immersed in diethylene glycol dimethyl ether at 40 ° C. for 30 minutes and then at 60 ° C.
/ 60 minutes immersion and release to obtain a plastic molded article to be treated. After that, diethylene glycol dimethyl ether was replaced with isopropyl alcohol, and 60 ° C /
A residual monomer extraction for 16 hours was performed. Thereafter, the plastic molded article to be treated is washed twice with isopropyl alcohol, and then isopropyl alcohol / purified water = 5.
0/50 (parts by weight) for 30 minutes, then immersed in isopropyl alcohol / purified water = 25/75 (parts by weight) for 30 minutes, further immersed in purified water for 16 hours, and isopropyl The alcohol was completely removed to obtain a plastic molded article to be treated. The above-mentioned plastic molded article to be treated is placed in a 0.5N-NaOH aqueous solution for 40 minutes.
C./24 hours. Thereafter, the plastic molded product was sufficiently washed with purified water, and then immersed in a borate buffer (pH 7.1 to 7.3) in the vial, and the vial was sealed. Place the vial in an autoclave,
/ 60 minutes boiling treatment. After allowing to cool, remove the plastic molded product from the vial, and add borate buffer (pH
7.1 to 7.3). The water content of this plastic molded product was 31%, and the advancing contact angle in the borate buffer was 54 °. The water wettability was ◎. Further, as for mechanical properties, the elastic modulus was 600 kPa. Further, the oxygen permeability coefficient is 106 × 10 ⁻¹¹ (cm ² / sec)
c) It was [mlO ₂ / (ml · hPa)].

[0022]

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Example 3 Tris (trimethylsiloxy) silylpropyl methacrylate (30.5 parts by weight), the compound (M1) (30.5 parts by weight), N, N-dimethylacrylamide (39 parts by weight), and a polymer having polymerizable groups at both terminals 2.5 parts by weight of dimethylsiloxane macromer (MW: 1,900) and 10 parts by weight of diethylene glycol dimethyl ether were uniformly mixed, and 0.2 part by weight of "Darocur 1173" (manufactured by CIBA) was added as a polymerization initiator. The monomer mixture was degassed under an argon atmosphere. It was injected between plastic molds in a glove box under a nitrogen atmosphere and sealed. Light irradiation using an insect lamp (illuminance 1 mW / cm ² , 1
(2 minutes) to carry out polymerization. Then, the mold was immersed in diethylene glycol dimethyl ether at 40 ° C.
/ 30 min, further immersion at 60 ° C./60 min, and release to obtain a plastic molded article to be treated. Thereafter, diethylene glycol dimethyl ether was replaced with isopropyl alcohol, and the remaining monomer was extracted at 60 ° C. for 16 hours. Thereafter, the plastic molded article to be treated is washed twice with isopropyl alcohol, and then immersed in isopropyl alcohol / purified water = 50/50 (parts by weight) for 30 minutes, and then isopropyl alcohol / purified water = 25.
/ 75 (parts by weight) for 30 minutes.
After immersion for 6 hours, isopropyl alcohol was completely removed from the plastic molded product to obtain a plastic molded product to be treated. The plastic molded article to be treated is 1.2
wt% polyacrylic acid (average molecular weight: 250,000)
It was immersed in an aqueous solution (pH 3.1) at 23 ° C. for 4 hours. Thereafter, the plastic molded product is sufficiently washed with purified water, and then a borate buffer (pH 7.1 to 7.3) in a vial bottle.
And the vial was sealed. The vial was placed in an autoclave and subjected to boiling at 120 ° C. for 30 minutes. After cooling, the plastic molded product was taken out of the vial and immersed in a borate buffer (pH 7.1 to 7.3). The moisture content of this plastic molded product is 32%,
The advancing contact angle in borate buffer was 24 °. The water wettability was ◎. Further, the mechanical properties are as follows:
It was 17 kPa. Furthermore, the oxygen permeability coefficient is 68 ×
^{10 -11 (cm 2 / sec)} [mlO 2 / (ml · hP
a)]. Example 4 Tris (trimethylsiloxy) silylpropyl methacrylate 21.33 parts by weight, the following compound (M3) 42.67 parts by weight, N, N-dimethylacrylamide 3
The same procedure was performed except that 6 parts by weight of diethylene glycol dimethyl ether was changed to ethylene glycol diacetate. The moisture content of this plastic molded product is 33%
And the advancing contact angle in borate buffer was 27 °.
The water wettability was ◎. Further, the elastic modulus of the mechanical properties was 558 kPa. Further, the oxygen permeability coefficient is 69 × 10 ⁻¹¹ (cm ² / sec) [mlO ₂ / (ml
HPa)].

[0024]

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Comparative Example 1 The procedure of Example 3 was repeated except that tris (trimethylsiloxy) silylpropyl methacrylate was changed to 60 parts by weight and N, N-dimethylacrylamide was changed to 40 parts by weight. The water content of this plastic molded product was 31%, and the advancing contact angle in borate buffer was 58 °. The water wettability was ◎. Further, the elastic modulus of the mechanical properties was 1165 kPa. Further, the oxygen permeability coefficient is 75 × 10 ⁻¹¹ (cm ² / sec) [mlO ₂ / (ml
HPa)]. Comparative Example 2 The procedure of Example 3 was repeated except that tris (trimethylsiloxy) silylpropyl methacrylate was changed to 50 parts by weight and N, N-dimethylacrylamide was changed to 50 parts by weight. The water content of this plastic molded product was 50%, and the advancing contact angle in the borate buffer was 41 °. The water wettability was ◎. Further, as for mechanical properties, the elastic modulus was 731 kPa. Further, the oxygen permeability coefficient is 42 × 10 ⁻¹¹ (cm ² / sec) [mlO ₂ / (ml ·
hPa)]. Comparative Example 3 In Example 3, 65 parts by weight of the compound of (M1), N,
All procedures were the same except that the amount was changed to 35 parts by weight of N-dimethylacrylamide. The water content of this plastic molded product was 39%, and the advancing contact angle in borate buffer was 65 °. The water wettability was ◎. Further, the elastic modulus of the mechanical properties was 483 kPa. Furthermore, the oxygen permeability coefficient is ^{52 × 10 -11 (cm 2 /} sec) [mlO 2
/ (Ml · hPa)]. Comparative Example 4 In Example 3, 20 parts by weight of a polydimethylsiloxane macromer (MW: 1,900) having a polymerizable group at both terminals, 40 parts by weight of tris (trimethylsiloxy) silylpropyl methacrylate, and N, N-dimethylacrylamide 40 The same procedure was carried out except that the amount was changed to parts by weight and triethylene glycol dimethacrylate was not blended. The water content of this plastic molded product was 28%, and the advancing contact angle in the borate buffer was 26 °. The water wettability was ◎. Further, the elastic modulus of the mechanical properties is 1407.
kPa. Furthermore, the oxygen permeability coefficient is 79 × 10
^{-1 1 (cm 2 / sec)} [mlO 2 / (ml · hPa)]
Met.

[0026]

According to the present invention, it is possible to obtain a plastic molded article having an excellent balance of various properties such as high oxygen permeability, low elastic modulus and high water content.

In particular, when the plastic molded article is an optical article such as a contact lens, an intraocular lens, a plastic lens, etc., the above-mentioned excellent performance is exhibited and an excellent product is obtained.

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Claims (4)

[Claims] An oxygen permeability coefficient of 60 × 10 ^-11 (cm ² / s)
ec) A plastic molded product having a modulus of [mlO ₂ / (ml · hPa)] or more and an elastic modulus of 275 to 830 kPa. 2. The plastic molded article according to claim 1, which contains silicon and / or fluorine atoms. 3. The plastic molded article according to claim 1, wherein the water content is 15% or more and 60% or less. 4. A contact lens comprising the plastic molded product according to claim 1.