JPH0519214A - Contact lens free from contamination - Google Patents

Abstract

PURPOSE:To obtain a contact lens on which contaminant due to tear and the like hardly adheres and to improve the balance in physical properties such as oxygen transmittance, mechanical strength, etc., by constituting the lens of copolymers obtd. by polymn. of bifunctional org. siloxane macromers having a specified structure and mol.wt. as the essential component. CONSTITUTION:This contact lens consists of copolymers obtd. by polymerizing only one or more kinds of bifunctional org. siloxane macromers expressed by formula I or polymerizing these macromers with one or more kinds of monomers polymerizable with these macromers. In formula I, R1 is hydrogen or methyl group, R2-R5 are hydrocarbon groups or trimethylsiloxane groups having 1-12 carbon number, R6 and R7 are hydrocarbon groups or fluorine-substd. hydrocarbon groups having 1-12 carbon number and at least one of them is the latter, l and n are integers from 1 to 20, p is an integer 0 to 20, m is an integer 4 to 100, and X is -NHCOO- or -OOCHN-R8-NHCOO- (R8 is a specified hydrocarbon group).

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a novel contact lens material. More specifically, the present invention relates to a material of a substantially water-free soft contact lens, which has little stain adhesion due to tears and the like and has a good balance of physical properties such as oxygen permeability.

[0002]

2. Description of the Related Art Soft contact lenses are classified into hydrous soft contact lenses and non-hydrous soft contact lenses. The hydrous soft contact lens is composed of a copolymer obtained by polymerizing a hydrophilic monomer such as hydroxyethyl methacrylate and N-vinylpyrrolidone as a main component, and a lens is prepared by cutting or casting method and swelled in physiological saline. The lens has a water content of about 40 to 70%.

As a non-hydrous soft contact lens, for example, a platinum-based catalyst is added to a mixture of polydimethylsiloxane whose both molecular chain ends are blocked with vinyldimethylsilyl groups and methylhydrogenpolysiloxane, and a molding method is used. Intermediate between soft contact lenses and hard contact lenses, which consists of a silicone rubber lens obtained by the method of heating and curing with a polymer and a polymer whose main component is polyperfluoroether with a polymerizable group such as a methacryloxy group added to both ends. Flexible lenses having the above elastic modulus are known (JP-A-54-81363, JP-A-58-127914).

Further, a hard substrate obtained by copolymerizing (meth) acrylic acid and (meth) acrylic ester is cut to prepare a lens, which is subjected to an esterification and / or transesterification treatment to give a feeling of wearing. A non-hydrous soft contact lens having excellent properties is also manufactured (Japanese Patent Laid-Open No. 48-750).
Issue 47). A contact lens material mainly composed of polyfunctional polysiloxane and having high oxygen permeability is also disclosed in JP-A-54-24.
047, JP-A-56-51715, JP-A-59-229524, and JP-A-2-188717.

Hydrous soft contact lenses are soft and comfortable to wear, and have advantages such as high oxygen permeability when they are of a high water content type, but they are easily damaged and inferior in durability and lacrimal fluid. It is often inconvenient to handle because it is apt to be contaminated by the ingredients inside and there is a risk of bacterial growth, so that it has to be boiled and disinfected regularly. Non-hydrous contact lenses also have the following problems.

[0006] First, regarding the silicone rubber lens, at the beginning of development, the hydrophilic treatment layer applied to improve the hydrophobicity of the lens surface is peeled off, or the elasticity is too large, so that adhesion to the cornea occurs. Although it has drawbacks, it has not been widely put into practical use, but recently, due to advances in surface hydrophilization treatment technology, changes in lens design, and improvements in mechanical properties, the aforementioned drawbacks have been considerably improved. Yes, but it is still not entirely satisfactory and the reality is that it is not widely used.

Next, since the non-water-containing lens containing polyperfluoroether as a main component is closer to a semi-hard type than a soft contact lens, it does not give a feeling of wearing like a soft contact lens, and it does not come on the cornea. The movement of the lens is not satisfactory either. Also (meta)
A soft contact lens mainly composed of an acrylic ester is inferior in oxygen permeability, and is not suitable for wearing for a long time.

None of the materials containing polyfunctional polysiloxane as a main component is closer to the silicone rubber lens, taking into consideration the contamination by the components in the tear fluid.

[0009]

Under these circumstances, the present invention is less likely to have stain adherence due to tears and the like, and has a commercially available oxygen permeability coefficient (DK value), optical characteristics and mechanical characteristics. It is made for the purpose of providing a substantially non-hydrated soft contact lens material that is as good as or better than that.

[0010]

DISCLOSURE OF THE INVENTION The inventors of the present invention have conducted extensive studies to develop a non-hydrous soft contact lens material having the above-mentioned preferable properties, and as a result, have found that the bifunctional compound has a specific structure and molecular weight. It was found that the object can be achieved by a material composed of a copolymer obtained by polymerizing an organosiloxane macromer as a main component, and based on this finding, the present invention could be completed.

That is, the present invention is as follows. A copolymer obtained by polymerizing one or more difunctional organosiloxane macromers represented by the following chemical formula 2 with only the difunctional organosiloxane macromers or with one or more copolymerizable monomers. It is a contact lens made of a polymer.

[0012]

[Chemical 2]

The present invention will be described in detail below. The bifunctional organosiloxane macromer represented by the formula (I) has a longer intermolecular chain as the molecular weight increases, so that the oxygen permeability is improved, the cohesive energy is lowered, and the glass transfer point is low. Therefore, when used as a soft contact lens, it has a great effect on the softness and physical properties such as shape retention indicated by rubber elasticity.

However, when the repeating number m of the siloxanyl unit of the macromer exceeds 100, the compatibility with the copolymerizable monomer is deteriorated, resulting in white turbidity or phase separation. The oxygen permeability also disappears when the number of repetitions m increases. Further, when the number of repetitions m is 4 or less, not only the oxygen permeability is lowered, but also the softness and flexibility required for the soft contact lens are deteriorated. For the above reason, the value of the repeating number m of the siloxanyl group which determines the molecular weight is in the range of 4 to 100, preferably 10 to 80 to provide the most balanced contact lens material.

Next, the side chain of the siloxanyl group is a hydrocarbon group having 1 to 12 carbon atoms or a fluorine-substituted hydrocarbon group, at least one of which must be a fluorine-substituted hydrocarbon group. By having a fluorine-substituted hydrocarbon group in the side chain, the critical surface tension is reduced due to the fluorine atom, resulting in water-repellent and oil-repellent properties. This has the effect of suppressing the surface of the contact lens from being contaminated by proteins, lipids, inorganic components, etc. in tear fluid, and has the property of easily peeling off even if contaminants adhere. As these fluorine-substituted hydrocarbon groups, for example, 3,3,3-trifluoropropyl group, 1,1,2,2-tetrahydroperfluorooctyl group, 1,1,2,2-tetrahydroperfluorodecyl group, etc. There is.

X in the formula (I) represents a residue of a monofunctional isocyanate represented by the following chemical formula 3 or a residue of a difunctional isocyanate represented by the following chemical formula 4.

[0017]

[Chemical 3]

[0018]

[Chemical 4]

By including these urethane bonds in the molecular structure, the strength and water leakage of the contact lens can be improved. As the residue of the bifunctional isocyanate, for example, hexamethylene diisocyanate, tetramethylene diisocyanate, 2,4,4-trimethyl-1,6-
Hexamethylene diisocyanate, 2,6-diisocyanate methyl caproate, 3-isocyanate methyl-3,5,5-trimethylcyclohexyl isocyanate, dicyclohexylmethane-4,4'-diisocyanate, hydrogenated xylylene diisocyanate, hydrogenated tolylene diisocyanate , There are residues such as isophorone diisocyanate.

In the formula (I), R ₁ is hydrogen or a methyl group, and R ₂ , R ₃ , R ₄ and R ₅ each have 1 to 1 carbon atoms.
It is a hydrocarbon group of 2 or a trimethylsiloxy group, and a hydrocarbon group of 1 to 3 carbon atoms or a trimethylsiloxy group is preferable from the viewpoint of softness, elasticity, strength and dirt adhesion of a contact lens. l and n are the same or different integers of 1 to 20, and p is an integer of 0 to 20. If the amount exceeds 20 and becomes large, the compatibility with other monomers deteriorates and white turbidity easily occurs, which is not preferable.

The bifunctional organosiloxane macromer represented by the formula (I) is, for example, 1,3-bis (4-hydroxyalkyl) tetramethyldisiloxane and 1,3,5.
A diol having a polysiloxane structure obtained by a ring-opening insertion reaction with trimethyltrifluoropropylcyclotrisiloxane is reacted with, for example, the same equivalent of isocyanate ethyl methacrylate, or a double equivalent of diisocyanate is reacted. It is obtained by reacting with hydroxyethyl methacrylate.

The contact lens of the present invention comprises a difunctional organosiloxane macromer represented by the formula (I), or one or more difunctional organosiloxane macromers alone or as a copolymerizable monomer. It consists of a cross-linked polymer obtained by polymerizing with one or more species. Depending on the target performance of the contact lens, such as oxygen permeability, softness, resistance to dirt, strength, etc., R in formula (I)
₆ , the type of R ₇ , the value of m, and the type of X are selected.

Examples of the monomer copolymerizable with the bifunctional organosiloxane oligomer in the present invention include trifluoroethyl acrylate, tetrafluoroethyl acrylate, tetrafluoropropyl acrylate, pentafluoropropyl acrylate, hexafluorobutyl acrylate, and hexafluorobutyl acrylate. Fluoroisopropyl acrylate, heptafluorobutyl acrylate,
One or more fluorine-containing monomers selected from acrylic acid fluoroalkyl esters such as octafluoropentyl acrylate and corresponding methacrylic acid fluoroalkyl esters, such as methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, tert- Butyl acrylate, isobutyl acrylate, n-hexyl acrylate, n-octyl acrylate, n-heptyl acrylate, n-nonyl acrylate, n-decyl acrylate, isodecyl acrylate, n-lauryl acrylate, tridecyl acrylate, n-dodecyl acrylate, cyclopentyl Acrylate, cyclohexyl acrylate, n-
One or more kinds of monomers selected from methacrylic acid alkyl esters such as stearyl acrylate and corresponding acrylic acid alkyl esters, for example, aromatic vinyl compounds such as styrene, t-butyl styrene and α-methyl styrene. One or more monomers, such as methacrylic acid, acrylic acid, itaconic acid, 2
-Hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl methacrylate, 2-hydroxypropyl acrylate, glycerol methacrylate, polyethylene glycol methacrylate, N, N'-dimethylacrylamide, N-methylacrylamide, dimethylaminoethyl methacrylate, methylenebis One or more hydrophilic monomers selected from acrylamide, diacetone acrylamide, N-vinylpyrrolidone, etc., such as ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, Pentaerythritol tetramethacrylate, Scan phenol A dimethacrylate, vinyl methacrylate, acrylates corresponding to acrylic methacrylate and methacrylates thereof, divinylbenzene, and the like one or more crosslinkable monomers selected from such triacrylate isocyanurate.

Acrylic acid fluoroalkyl ester and methacrylic acid fluoroalkyl ester used as copolymerizable monomers in the present invention have water-repellent and oil-repellent properties due to the reduction of the critical surface tension due to the fluorine atom. Has the effect of preventing the contact lens surface from being contaminated by components such as proteins and lipids in tear fluid. Further, the monomer component preferably has a glass transition point of room temperature or lower in terms of physical properties, and when copolymerized, it can exhibit the softness and flexibility required for a soft contact lens.

Further, the acrylic acid ester monomer and the methacrylic acid ester monomer used as the copolymerizable monomer in the present invention have the effect of improving the compatibility between the bifunctional organic siloxane and the (meth) acrylic acid fluoroalkyl ester. Yes, it greatly expands the range of use. It is preferable to lower the glass transition point of the copolymer to room temperature or 0 ° C. or lower. Since these reduce the cohesive energy, they have the effect of imparting rubber elasticity and softness to the copolymer.

Good balance of characteristics such as optical characteristics of contact lens, oxygen permeability, mechanical strength, deformation recovery, stain adhesion when worn on the eye, dimensional stability in tear fluid and its change with time. Therefore, a mixed monomer in which these copolymerizable monomers are combined can be used. Examples of mixed monomers copolymerizable with the difunctional organosiloxane macromer of the present invention include trifluoroethyl acrylate, n-butyl acrylate, a combination of methacrylic acid and ethylene glycol dimethacrylate, hexafluoroisopropyl acrylate, n-butyl acrylate. , A combination of methacrylic acid and diethylene glycol dimethacrylate.

The copolymer used as the contact lens material of the present invention is a cast polymerization method in which a monomer mixture is filled in a mold and radical-polymerized by a known method, and the monomer mixture is charged in a rotating half-face mold. To polymerize with,
Alternatively, the copolymer can be formed into a contact lens by a method such as freeze cutting at a low temperature. The method of copolymerization is
Photoinitiators such as benzoin, benzophenone and benzyldimethylketanol are present in the monomer mixture,
A method of polymerizing by irradiating ultraviolet rays or a method of thermally polymerizing by using an azo compound such as azobisisobutyronitrile, benzoyl peroxide, lauroyl peroxide or an organic peroxide is preferable.

[0028]

EXAMPLES The present invention will be described in more detail by way of examples, which should not be construed as limiting the invention thereto. In addition, each physical property and molecular weight were calculated as follows. (1) Oxygen permeability coefficient Gas permeability measuring device K-315 manufactured by Rika Seiki Co., Ltd.
-N was used. The sample piece has a diameter of 30 mm and a thickness of 0.3 mm
The disk-shaped sample of was subjected to measurement, and the oxygen permeation coefficient was calculated from the slope of the straight line on the obtained chart. The measurement was carried out in a thermostatic chamber at 25 ° C. and at a sample piece setting place of 35 ° C. (2) Contact angle Contact Angle manufactured by Kyowa Interface Science Co., Ltd.
Meter CA-A was used. Prior to measurement, the sample piece was mirror-polished, the surface was cleaned with a surfactant, and the sample piece was immersed in physiological saline for 24 hours and then used for measurement. For the measurement, the sample piece is allowed to stand in pure water, a bubble with a diameter of 1.5 to 2.0 mm is brought into contact with the lower surface of the sample piece with a syringe, the angle formed by the bubble and the sample piece is read, and the contact angle is calculated. I asked. (3) Tensile strength A universal tensile compression tester SV-50 manufactured by Imada Manufacturing Co., Ltd. was used. A sample piece having a thickness of 0.3 mm, a width of 5.0 mm and a length of 30 mm was used for the measurement. Tensile speed is 10mm
It was / min. The measurement was performed three times on the same sample piece, and the tensile strength was determined from the obtained value according to the calculation method described in JIS-K-6301. (4) Staining Adhesion, Japan Contact Lens Society, 45 p. 277-28
3 (1982), a stain adhesion test was conducted. A sample piece having a thickness of 2 mm, a width of 5 mm and a length of 30 mm was used. Judgment was based on the adhesion of dirt when a PMMA sample piece was operated in the same manner as a control, and when the degree of dirt adhesion was less than that by visual observation, it was "small", when it was large, it was "large", and when it was equivalent. “Equivalent” In addition,
Three types of mucin (bovine gastric mucosa), lysozyme (egg white), and lecithin (egg yolk) were used as soil substance models. (5) Hardness In accordance with the method described in JIS-K-6301, the hardness (Sho
re A) Measured. (6) Molecular weight M of bifunctional organosiloxane oligomer
By measuring n, m was calculated.

Liquid chromatograph: LC-3A type [manufactured by Shimadzu Corporation] Column: Shodex 802 + 803 + 805 [manufactured by Showa Denko KK] Detector: ERC-7510S [manufactured by Elma Optical Co., Ltd.] Integrator : 7000A [manufactured by System Instruments] Developing solvent: Tetrahydrofuran Temperature: 25 ° C Reference polymer for molecular weight calibration curve: Monodisperse polystyrene various [Mw / Mn = 1.2 (max)] [manufactured by Toyo Soda Co., Ltd.]

[0030]

Example 1 Organosiloxane macromers represented by the following chemical formula 5 and having hydroxyl groups at both ends (number average molecular weight Mn≈65
00, m≈40) equipped with a cooler, a thermometer, and a stirrer 5
70 g (0.01079) in a 00 ml brown round bottom flask.
mol), 2-isocyanatoethyl methacrylate (3.4 g, 0.0216 mol) was added thereto, 5 drops of dibutyltin dilaurate and tetrahydrofuran were further added, and the mixture was stirred at 70 ° C. under N ₂ atmosphere at 4 ° C.
Reacted for hours. The disappearance of the absorption based on the isocyanate group was confirmed by the infrared absorption spectrum.

[0031]

[Chemical 5]

After cooling, about 300 m of tetrahydrofuran
1, activated carbon for decolorization and magnesium sulfate for dehydration were added and left overnight. Then, after filtering through a 0.2 μm Teflon filter, low boiling point substances such as tetrahydrofuran were removed using an evaporator, and 55 g of a transparent and slightly viscous liquid was obtained. The structure of this liquid was analyzed by NMR (proton nuclear magnetic resonance spectrum), and as a result, it was confirmed that the liquid was an organosiloxane macromer represented by Chemical formula 6.

[0033]

[Chemical 6]

55 parts by weight of the organosiloxane macromer containing the urethane bond shown in Chemical formula 6, 25 parts by weight of trifluoroethyl acrylate (hereinafter referred to as 3FA), 20 parts by weight of n-butyl acrylate (hereinafter referred to as n-BA), and methacrylic acid. 6 parts by weight (hereinafter referred to as MAA), 5 parts by weight of ethylene glycol dimethacrylate (hereinafter referred to as ED) and 0.5 parts by weight of benzyl dimethyl ketanol were added, and the mixture was stirred in a nitrogen atmosphere with a magnetic stirrer for about 1 hour, Dissolved and mixed.

Then, in a nitrogen atmosphere, two glass plates (thickness: 10) with a silicone rubber gasket interposed therebetween.
mm, width 60 mm, length 90 mm), the reaction solution was injected into a cell, and the cell was irradiated with ultraviolet rays at a temperature of 40 to 50 ° C. for 2 hours to obtain a transparent copolymer. The oxygen permeability coefficient, contact angle, tensile strength, stain adhesion and hardness of the thus obtained copolymer were measured. The results are shown in Table 1.

Then, the above-mentioned reaction solution was injected and filled into a polypropylene concave-convex mold (lens diameter: 13.7 mm) prepared by injection molding, and irradiated with ultraviolet rays for 2 hours. The lens taken out from the mold after the irradiation was transparent and showed flexibility, and had good strength.

[0037]

Example 2 An organosiloxane macromer represented by the following chemical formula 7 and having hydroxyl groups at both ends (number average molecular weight Mn≈96
00, m≈60) was reacted with 2-molar amount of 2-isocyanatoethyl methacrylate in the same manner as in Example 1,
When purified, an organosiloxane McMallow having a urethane bond represented by the following chemical formula 8 was obtained.

[0038]

[Chemical 7]

55 parts by weight of macromer represented by the following chemical formula 8, 3 parts by weight of 3FA, 20 parts by weight of n-BA, MAA6
Parts by weight, 4 parts by weight of ED, and 0.5 parts by weight of benzyl dimethyl ketanol were added and polymerized in the same manner as in Example 1 to obtain a transparent copolymer.

[0040]

[Chemical 8]

The results of measuring the physical properties of the obtained copolymer are shown in Table 1.

[0042]

Example 3 70 g (0.01079 mol) of the macromer represented by Chemical formula 5 used in Example 1 was charged in a 500 ml round bottom flask equipped with a condenser and a thermometer stirrer.
Isophorone diisocyanate 4.79 g (0.0
216 mol), 0.02 g of triethylamine, and tetrahydrofuran are added, and the mixture is stirred in a N ₂ atmosphere while
The reaction was carried out at 60 ° C. for about 5 hours.

Then, 2.81 g (0.0216 mol) of 2-hydroxyethyl methacrylate and 5 drops of dibutyltin dilaurylate were added to the reaction solution, and the mixture was further reacted in an N ₂ atmosphere at 70 ° C. for 5 hours. After cooling, about 300 ml of tetrahydrofuran was added, activated carbon for decolorization and magnesium sulfate for dehydration were added, and the mixture was left for 2 nights. 0.2
After filtering with a μ Teflon filter, low-boiling substances such as tetrahydrofuran were removed by an evaporator to obtain about 43 g of a viscous transparent liquid. NMR of this liquid
As a result of analyzing the structure by (proton nuclear magnetic resonance spectrum), it was confirmed to be an organosiloxane macromer represented by the following chemical formula 9.

[0044]

[Chemical 9]

55 parts by weight of macromer shown in Chemical formula 9 above, 25 parts by weight of 3FA, 20 parts by weight of n-BA, MAA6
Parts by weight, 4 parts by weight of ED, and 0.5 parts by weight of benzyl dimethyl ketanol were added and polymerized in the same manner as in Example 1 to obtain a transparent copolymer. The results of measuring the physical properties of the obtained copolymer are shown in Table 1.

[0046]

COMPARATIVE EXAMPLE 1 An organosiloxane macromer having a hydroxyl group at both ends represented by the following chemical formula 10 (number average molecular weight Mn≈2
000, m≈24) was reacted with 2-isocyanatoethyl methacrylate in the same manner as in Example 1, and then purified and the structure was analyzed by NMR. As a result, it was confirmed that the organosiloxane macromer represented by the following chemical formula 11 was obtained. did.

[0047]

[Chemical 10]

[0048]

[Chemical 11]

55 parts by weight of macromer shown in Chemical formula 11 above, 25 parts by weight of 3FA, 20 parts by weight of n-BA, MAA6
Parts by weight, 4 parts by weight of ED, and 0.5 parts by weight of benzyl dimethyl ketanol were added and polymerized in the same manner as in Example 1 to obtain a transparent copolymer. The results of measuring the physical properties of the obtained copolymer are shown in Table 1.

[0050]

[Table 1]

[0051]

EFFECT OF THE INVENTION The soft contact lens material of the present invention has excellent stain resistance comparable to that of a polymethylmethacrylate hard contact lens, and has oxygen permeability and mechanical strength equal to or higher than that of a commercially available product. It is a well-balanced material.

Claims (1)

Claim: What is claimed is: 1. A difunctional organic siloxane macromer represented by the following chemical formula 1 is used alone or in combination with at least one of the difunctional organic siloxane macromers. A contact lens comprising a polymer obtained by polymerizing one or more polymerizable monomers. [Chemical 1]