HK1069211A - Oxygen-permeable hard contact lens - Google Patents
Oxygen-permeable hard contact lens Download PDFInfo
- Publication number
- HK1069211A HK1069211A HK05101574.7A HK05101574A HK1069211A HK 1069211 A HK1069211 A HK 1069211A HK 05101574 A HK05101574 A HK 05101574A HK 1069211 A HK1069211 A HK 1069211A
- Authority
- HK
- Hong Kong
- Prior art keywords
- oxygen
- lens
- meth
- contact lens
- hard contact
- Prior art date
Links
Description
Technical Field
The present invention relates to oxygen permeable hard contact lenses. The oxygen-permeable hard contact lens of the present invention has a small central thickness, high oxygen supply capability to the cornea, excellent safety, less breakage during use, and high durability.
Background
Since a contact lens is a vision correction tool used in direct contact with the eye (cornea), it is naturally a necessary condition that the contact lens has excellent optical characteristics and sufficient safety. The cornea is a bloodless tissue, and oxygen from the atmosphere is indispensable for maintaining the metabolic activity of corneal cells. Therefore, in order to improve oxygen permeability, material development has been vigorously developed, and as a result, various contact lens materials and contact lenses having high oxygen permeability coefficients have been developed. For example, Japanese patent application laid-open No. 6-41242 proposes an ophthalmic lens material containing a silicon-containing styrene derivative and a fluorinated alkyl ester-containing styrene derivative as essential components.
However, conventional contact lenses having a high oxygen permeability have a drawback that the destruction strength against impact or bending is reduced as the oxygen permeability is increased, and the lenses are easily broken.
In order to overcome this drawback, a method for producing an oxygen-permeable contact lens which has a higher compressive breaking strength than conventional lenses and is less likely to break has been proposed (Japanese patent application laid-open No. 11-314283). However, the strength of the contact lens obtained by this method is improved, but the level of durability is not achieved. In particular, when a damaged lens is attached and detached, or handled, the lens may be repeatedly subjected to stress and damaged.
The present invention has been made in view of the above-mentioned conventional techniques, and an object of the present invention is to provide an oxygen-permeable hard contact lens which can supply physiologically sufficient oxygen to the cornea and has excellent durability.
DISCLOSURE OF THE INVENTION
The invention relates to an oxygen-permeable hard contact lens having a value of the vertex refractive power of-6.00D or more, characterized by containing an oxygen permeability coefficient of 20 x 10-11cm3·cm/cm2Sec mmHg or more and a center thickness of the lens is 0.010 to 0.125 mm.
Best Mode for Carrying Out The Invention
The oxygen-permeable hard contact lens of the present invention has a center thickness of 0.010 to 0.125mm and a value of the vertex refractive power of-6.00D or more.
In the present specification, "center thickness of the lens" means the thickness of the center portion (optical center) of the optical portion of the lens, and "value of the vertex refractive power" means the refractive index of the lens. In the case of a spherical lens, as the value of the vertex refractive power decreases, the difference in curvature between the front and rear surfaces of the lens increases, and therefore the thickness of the edge portion of the lens inevitably increases. Therefore, even if the center thickness is made thin in order to make the thickness of the entire lens thin, the strength of the lens can be maintained by the thickness of the edge portion. On the other hand, as the value of the vertex refractive power increases, the difference in curvature between the front surface and the rear surface of the lens decreases, and therefore, if the center thickness is made thinner in order to make the entire lens thinner, the thickness of the edge portion also becomes thinner, and the strength of the lens decreases. Therefore, from the viewpoint of strength, an oxygen-permeable contact lens having a value of-6.00D or more of the refractive power at the apex, which is generally commercially available, has a center thickness of 0.150mm or more.
In the present invention, the oxygen permeability coefficient will be 20X 10 in view of the center thickness of the lens-11cm3(STP)·cm/cm2When the center thickness of the contact lens made of a raw material of sec · mmHg or more is set in the above range, it is found that insufficient strength which does not cause a problem in actual use is generated, the lens is easily bent, and stress is easily dispersed throughout the lens, so that durability of the lens against stress repeatedly applied to the lens (durability in an actual use environment) is remarkably improved.
When the center thickness of the lens exceeds 0.125mm, the rigidity of the lens increases and stress concentrates at a place where deformation is large (a place where stress is weak), so that durability against repeated stress decreases, and when the center thickness is less than 0.010mm, the shape retention ability of the lens decreases and vision correction ability decreases. From the viewpoint of visual acuity correction ability and durability against repeated stress, the center thickness of the lens is preferably in the range of 0.050 to 0.120mm, and more preferably in the range of 0.070 to 0.105 mm.
In the oxygen-permeable hard contact lens of the present invention, from the viewpoint of visual acuity correction ability and durability against repeated stress, vickers hardness, which is an index of ease of bending (rigidity of the lens), of the lens, is preferably in the range of 5 to 15, and more preferably in the range of 5 to 10. From the same viewpoint, the oxygen-permeable hard contact lens of the present invention preferably has a compression elastic modulus in the range of 10 to 100gf, more preferably 20 to 90 gf. The compression modulus of elasticity is an index of the degree of difficulty of bending of the lens, and if the value is small, the lens is easily bent, and if the value is large, the rigidity of the lens is large.
Polymerization for use in oxygen permeable hard contact lenses of the inventionThe oxygen permeability coefficient of the material is 20 x 10-11cm3·cm/cm2Sec mmHg or more.
The "oxygen permeability coefficient" referred to in the present specification is represented by the product of the solubility coefficient of oxygen in a polymer and the diffusion coefficient of oxygen in a polymer, and specifically means a value measured by the contact lens association standard measurement method "oxygen permeability measurement method for hard contact lenses".
The oxygen permeability coefficient of the polymer is less than 20 x 10-11cm3·cm/cm2In the case of sec mmHg, physiologically sufficient oxygen cannot be supplied to the cornea, and oxygen on the cornea is insufficient, which may cause eye disorders. Further, if the oxygen permeability coefficient of the polymer is increased, the stain resistance tends to be lowered. Therefore, from the viewpoint of oxygen permeability and contamination resistance of the lens, the oxygen permeability coefficient of the polymer is preferably 20X 10-11～200×10-11cm3·cm/cm2Sec mmHg, more preferably 20X 10-11～150×10-11cm3·cm/cm2Sec. mmHg, more preferably 20X 10-11～100×10-11cm3·cm/cm2Sec. mmHg.
The polymer constituting the oxygen-permeable hard contact lens of the present invention can be suitably selected and used from known polymers used for oxygen-permeable hard contact lenses, but from the viewpoint of improving the oxygen permeability coefficient, a polymer containing a monomer unit having a siloxane group (シロキサニル) is preferable. Examples of such monomers include (meth) acrylates having a siloxane group such as tris (trimethylsiloxy) silylpropyl (meth) acrylate, heptamethyltrisiloxaneethyl (meth) acrylate, pentamethyldisiloxy (meth) acrylate, isobutylhexamethyltrisiloxane (meth) acrylate, methyldi (trimethylsiloxy) - (meth) acryloyloxymethylsilane, n-propyloctamethyltetrasiloxane propyl (meth) acrylate, pentamethyldi (trimethylsiloxy) - (meth) acryloyloxymethylsilane, and tert-butyltetramethyldisiloxane ethyl (meth) acrylate; (meth) acrylamides having a siloxane group such as N- [ tris (trimethylsiloxy) silylpropyl ] (meth) acrylamide, N- (heptamethyltrisiloxaneoethyl) (meth) acrylamide, N- (pentamethyldisiloxanyl) (meth) acrylamide, N- (isobutylhexamethyltrissiloxanyl) (meth) acrylamide, N- (N-propyl octamethyltetrasiloxane propyl) (meth) acrylamide, N- (tert-butyltetramethyldisiloxanylethyl) (meth) acrylamide, and the like. Among them, from the viewpoint of durability against repeated stress and stain resistance, (meth) acrylamide having a siloxane group is preferable, and N- [ tris (trimethylsiloxy) silylpropyl ] (meth) acrylamide is more preferable. The above-mentioned siloxane group-containing monomers may be used alone in 1 kind, or may be used in combination of 2 or more kinds.
In the present specification, "(meth) acrylate" means "acrylate" and/or "methacrylate". "(meth) acryloyloxymethylsilane" means "acryloyloxymethylsilane" and/or "methacryloyloxymethylsilane". Further, "(meth) acrylamide" means "acrylamide" and/or "methacrylamide".
By using a polymer containing a monomer unit having a fluorine atom in addition to the above-mentioned monomer unit having a siloxane group, a contact lens having a high oxygen permeability coefficient and oxygen permeability, excellent contamination resistance, and an excellent overall balance can be obtained.
Examples of the monomer having a fluorine atom include fluoroalkyl (meth) acrylates such as 2, 2, 2-trifluoroethyl (meth) acrylate, 2, 2, 2 ', 2 ', 2 ' -hexafluoroisopropyl (meth) acrylate, 2, 2, 3, 3, 4, 4, 4-heptafluorobutyl (meth) acrylate, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 8-pentadecafluorooctyl (meth) acrylate, and 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 9, 9-decahexafluorononyl (meth) acrylate, and 1 or 2 or more of these monomers can be used. In order to obtain a polymer having a desired oxygen permeability coefficient, the weight ratio of the monomer unit having a siloxane group to the monomer unit having a fluorine atom is preferably in the range of 70: 30 to 30: 70, and the total amount of the monomer unit having a siloxane group and the monomer unit having a fluorine atom is preferably 30 to 70% by weight based on the total weight of the polymer.
From the viewpoint of shape stability, the polymer constituting the oxygen-permeable hard contact lens of the present invention preferably contains a monomer unit having at least 2 polymerizable groups in the molecule.
Examples of the monomer having at least 2 polymerizable groups in the molecule include alkylene glycol di (meth) acrylates such as ethylene glycol di (meth) acrylate and diethylene glycol di (meth) acrylate; trimethylolpropane tri (meth) acrylate; tetra-or tri (meth) acrylate of pentaerythritol, and the like. These monomers having at least 2 polymerizable groups may be used alone in 1 kind, or 2 or more kinds may be used in combination. When the polymer contains a monomer unit having at least 2 polymerizable groups, the content of the monomer unit is preferably 0.1 to 20% by weight based on the total weight of the polymer. When the content of the monomer unit is less than 0.1% by weight, the shape stability of the obtained lens tends to be lowered, and when it exceeds 20% by weight, the obtained lens tends to be brittle.
In addition, from the viewpoint of improving wettability with water, it is preferable that the polymer constituting the oxygen-permeable hard contact lens of the present invention contains a hydrophilic monomer unit.
Examples of the hydrophilic monomer include hydroxyl group-containing (meth) acrylates such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and 2-hydroxybutyl (meth) acrylate; unsaturated carboxylic acids such as acrylic acid, methacrylic acid, itaconic acid, fumaric acid, maleic acid, and cinnamic acid; (meth) acrylamides such as acrylamide, methacrylamide, dimethylacrylamide, and diethylacrylamide; alkylene oxide (meth) acrylates such as glycidyl (meth) acrylate; alkylene glycol (meth) acrylates such as polyethylene glycol mono (meth) acrylate and polypropylene glycol mono (meth) acrylate; n-vinyl-2-piperidone, N-vinyl-2-pyrrolidone, N-vinyl-6-caprolactam, N-vinyl-3-methyl-2-pyrrolidone, N-vinyl-3-methyl-piperidone, N-vinyl-3-methyl-6-caprolactam, N-vinyl-4-methyl-2-pyrrolidone, N-vinyl-4-methyl-2-piperidone, N-vinyl-4-methyl-6-caprolactam, N-vinyl-5-methyl-2-pyrrolidone, N-vinyl-5-methyl-2-piperidone, N-methyl-2-pyrrolidone, N-vinyl-5-methyl-caprolactam, N-methyl-2-pyrrolidone, N-vinyl-2-pyrrolidone, N-methyl, N-vinyl-5-methyl-6-caprolactam, N-vinyl-6-methyl-6-caprolactam, N-vinyl-3-ethyl-2-pyrrolidone, N-vinyl-4, 5-dimethyl-2-pyrrolidone, N-vinyl-5, 5-dimethyl-2-pyrrolidone, N-vinyl-3, 3, 5-trimethyl-2-pyrrolidone, N-vinyl-5-methyl-5-ethyl-2-pyrrolidone, N-vinyl-3, 4, 5-trimethyl-3-ethyl-2-pyrrolidone, N-vinyl-3, 4, 5-dimethyl-2-pyrrolidone, N-methyl-6-caprolactam, N-vinyl-3-ethyl-2-pyrrolidone, N-vinyl-4, 5-dimethyl-2-pyrrolidone, N-vinyl-5-methyl, N-vinyllactams such as N-vinyl-6-methyl-2-piperidone, N-vinyl-6-ethyl-2-piperidone, N-vinyl-3, 5-dimethyl-2-piperidone, N-vinyl-4, 4-dimethyl-2-piperidone, N-vinyl-5-ethyl-6-caprolactam, N-vinyl-3, 5-dimethyl-6-caprolactam, N-vinyl-4, 6-dimethyl-6-caprolactam and N-vinyl-2, 4, 6-trimethyl-6-caprolactam; vinyl pyridine, and the like. These hydrophilic monomers may be used alone in 1 kind, or in combination of 2 or more kinds. When the hydrophilic monomer unit is contained in the polymer, the content of the monomer unit is preferably 0.1 to 20% by weight based on the total weight of the polymer. When the content of the monomer unit is less than 0.1% by weight, the water wettability of the resulting lens tends to be low, and when it exceeds 20% by weight, the water absorption of the resulting lens increases and the strength is lowered.
Furthermore, the polymer constituting the oxygen-permeable hard contact lens of the present invention preferably contains alkyl (meth) acrylate units from the viewpoint of improving strength. Examples of the alkyl (meth) acrylate include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, n-hexyl (meth) acrylate, cyclohexyl (meth) acrylate, and octadecyl (meth) acrylate, and these alkyl (meth) acrylates may be used alone in 1 kind or in combination of 2 or more kinds. When the polymer contains an alkyl (meth) acrylate unit, the content of the alkyl (meth) acrylate unit is preferably 0.1 to 20% by weight based on the total weight of the polymer. When the content of the monomer unit is less than 0.1% by weight, the strength of the obtained lens tends to be lowered, and when it exceeds 20% by weight, the oxygen permeability of the obtained lens is lowered.
The polymer constituting the oxygen-permeable hard contact lens of the present invention may contain, if necessary, other monomer units than the above-mentioned monomer units, within a range not to impair the object of the present invention. Examples of such monomer units include vinyl esters of fatty acids derived from vinyl acetate, vinyl butyrate, vinyl laurate, and the like; and itaconic acid diester units such as dimethyl itaconate and diethyl itaconate, and these monomer units may be used alone or in combination of 1 or more. When these monomer units are contained in the polymer, it is preferable to make the content of the monomer units to be about 10% by weight or less based on the total weight of the polymer, from the viewpoint of obtaining a polymer having the above-mentioned excellent characteristics and an oxygen-permeable hard contact lens.
In the present invention, a coloring matter may be contained in order to obtain a colored oxygen-permeable hard contact lens.
Oxygen-permeable hard contact lenses can be produced by polymerizing a polymerizable composition containing the above monomers in a desired ratio to form a contact lens shape. As the polymerization method, a method generally used for polymerizing a polymerizable monomer can be used, and a method of adding 1 or 2 of a thermally activated polymerization initiator and an energy ray (light or the like) activated polymerization initiator to a polymerizable composition and carrying out thermal polymerization or photopolymerization can be generally used. Among these methods, it is preferable to heat-polymerize the polymerizable composition using a thermally activated polymerization initiator in order to obtain a contact lens free from optical distortion.
When the polymerizable composition is heated and polymerized using the thermally activated polymerization initiator, it is preferable to use a thermostatic bath, a heated air circulation type heating apparatus, or the like, which is easy to adjust the temperature. Examples of the thermally activated polymerization initiator include peroxide-based thermally activated polymerization initiators such as benzoyl peroxide, isopropyl peroxide, lauroyl peroxide and methyl ethyl ketone peroxide; azo-based thermally activated polymerization initiators such as 2, 2 ' -azobisisobutyronitrile, 2 ' -azobisisobutyrate, 2 ' -azobisdimethylvaleronitrile, 2 ' -azobisisobutylamide and dimethyl 2, 2 ' -azobisisobutyrate, 1 or 2 or more types of these thermally activated polymerization initiators can be used.
The amount of the polymerization initiator is not particularly limited, and is usually 0.001 to 2 parts by weight based on 100 parts by weight of the total polymerizable composition to be polymerized.
In the production of contact lenses, conventional methods for producing plastic contact lenses can be employed, for example, (1) レ - スカット method in which a polymerizable composition is polymerized and molded, and the resulting molded article is cut and polished to produce contact lenses; (2) a molding method in which a polymerizable composition is filled into a mold having a mold cavity corresponding to a contact lens and polymerized and molded in the mold to produce a contact lens; (3) a spin casting method in which a polymerizable composition is dropped onto a mold surface rotating at a high speed around a rotating shaft, and the polymerizable composition is polymerized and molded while being radially cast and diffused on the mold surface to produce a contact lens; (4) the blank molding method for producing a contact lens by filling a polymerizable composition into a mold having a mold cavity capable of molding one surface of a contact lens, polymerizing and molding the composition in the mold, and cutting and polishing the other surface is not particularly limited.
In addition, the oxygen-permeable hard contact lens of the present invention is not particularly limited as to the diameter of the lens, the diameter of the optical portion of the lens, the thickness of the optical portion other than the optical center, the radius (radius of curvature) of the lens peripheral portion on the front curve side, the radius (radius of curvature) on the base curve side, the radius (radius of curvature) of the bevel curve, the bevel width, and other dimensions, except for the thickness of the center of the lens being 0.010 to 0.125mm, and can be appropriately determined. Generally, the diameter of the lens is 8.0 to 11.0mm, the diameter of the optical part is 5.0 to 10.5mm, the radius (curvature radius) of the lens peripheral part on the front bending side is 6.0 to 10.0mm, the radius (curvature radius) of the base bending side is 7.0 to 10.0mm, the radius (curvature radius) of the slope bending side is 8.0 to 12.0mm, and the width of the slope is preferably 0 to 2 mm.
The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. In the following examples, the vickers hardness, oxygen permeability coefficient, oxygen permeability, compression elastic modulus, compressive bending strength, and durability to repeated stress of the oxygen permeable hard contact lens were measured or evaluated as follows.
[ Vickers hardness ]
The oxygen-permeable hard contact lenses obtained in the following examples and comparative examples were measured for Vickers hardness by a Vickers hardness tester (manufactured by AKASHI).
[ oxygen permeability coefficient and oxygen permeability ]
The oxygen permeability coefficient of the copolymers obtained in the following examples and comparative examples was measured by using a scientific research type oxygen permeability meter (manufactured by seiko industries, ltd.) according to the contact lens association standard test method "method for measuring oxygen permeability of hard contact lenses". The oxygen permeability coefficient thus obtained was divided by the center thickness of the lens to obtain a value as the oxygen permeability.
[ compression spring rate ]
For the contact lenses obtained in the following examples and comparative examples, a compression bending test was conducted in accordance with the contact lens association standard test method "method for compression bending test of contact lens" except that the compression speed was changed from 200 mm/min to 10 mm/min. The compressive modulus of elasticity is defined as the stress at which a tangent line to the onset of denaturation of the stress-strain curve obtained by the compression bending test is extended to the diameter of the lens. In the test, "autograph IM-100 model", manufactured by Shimadzu corporation, was used.
[ compressive bending Strength ]
The oxygen-permeable hard contact lenses obtained in the following examples and comparative examples were subjected to a compression bending test in accordance with the contact lens association standard test method "method for testing compression bending of contact lenses". In the test, "autograph IM-100 model", manufactured by Shimadzu corporation, was used.
[ durability against repeated stress ]
Contact lenses are usually attached and detached daily, and the lenses are damaged or repeatedly stressed by handling at this time. As a durability test in consideration of the use environment, a new evaluation method is developed in the present invention. A lens obtained by rubbing the oxygen-permeable hard contact lenses obtained in the following examples and comparative examples for 15 seconds with a polishing agent having a particle size of 20 μm was used as a test piece. The test piece was subjected to a durability test against repeated stress at a compression rate of 100 mm/min and an amplitude of 3mm according to JIS K-7119, "method for testing plane bending fatigue of rigid plastic flat plate", and the number of times each lens was broken was measured. In addition, the case of no fracture even when 1000 times of repeated stress was applied is described as 1000 times.
The contents of the polymerizable monomers used in the following examples, comparative examples and tables are summarized in table 1.
TABLE 1
| Polymerizable monomer | |
| Shorthand writing | Compound (I) |
| N-TRISO-TRIS3FM6FMMMADMAAEGDMA | N- [ tris (trimethylsiloxy) silylpropyl group]Methacrylamide tris (trimethylsiloxy) silylpropyl methacrylate 2, 2, 2-trifluoroethyl methacrylate2, 2, 2, 2 ', 2 ', 2 ' -hexafluoroisopropyl methacrylate methyl N, N-dimethylacrylamide methylene glycol dimethacrylate |
Examples 1 to 8 and comparative examples 1 to 2
(1) To 10.0g of the polymerizable composition shown in Table 2, 0.01g of azobisisobutyronitrile was added as a thermally activated polymerization initiator, and the mixture was placed in a test tube (capacity: 20mL) made of polypropylene, and sealed after being replaced with nitrogen gas. The resulting mixture was immersed in a constant-temperature water bath at 55 ℃ for 24 hours, and after polymerization, the mixture was transferred to a hot air circulation type heating apparatus at 100 ℃ and held for 2 hours to complete the polymerization. After cooling, the polymer was taken out of the test tube.
(2) Oxygen-permeable hard contact lenses having diameters, values (degrees) of base curve, vertex refractive power, and center thickness shown in table 3 were produced by a cutting and polishing method using the polymer obtained in the above (1), and vickers hardness, oxygen permeability coefficient, oxygen permeability rate, compression elastic rate, compression flexural strength, and durability were measured or evaluated according to the above methods. The results are shown in Table 4.
Comparative examples 3 to 4
The Vickers hardness, the compression modulus of elasticity, the compression flexural strength and the durability of the oxygen-permeable hard contact lenses commercially available as shown in tables 2 and 3 (comparative example 3: oxygen-permeable hard contact lens A composed of a copolymer containing a methacrylate having a siloxane group and a methyl methacrylate as main components, comparative example 4: oxygen-permeable hard contact lens B for continuous use composed of a copolymer containing a silicon-containing styrene derivative and a fluoromethyl methacrylate as main components) were measured or evaluated in the manner described above. The results are shown in Table 4. Further, as for the oxygen permeability coefficient, values described in the catalog are transferred.
TABLE 2
| Proportion of monomer Unit in Polymer (% by weight) | |||||||
| N-TRIS | O-TRIS | 3FM | 6FM | MMA | DMAA | EGDMA | |
| Example 1 | 40 | - | 30 | - | 10 | 10 | 10 |
| Example 2 | 40 | - | 30 | - | 10 | 10 | 10 |
| Example 3 | 40 | - | 30 | - | 10 | 10 | 10 |
| Example 4 | 50 | - | 20 | - | 10 | 10 | 10 |
| Example 5 | 30 | - | 40 | - | 10 | 10 | 10 |
| Example 6 | 40 | - | - | 30 | 10 | 10 | 10 |
| Example 7 | - | 40 | 30 | - | 10 | 10 | 10 |
| Example 8 | - | 40 | - | 30 | 10 | 10 | 10 |
| Comparative example 1 | 40 | - | 30 | - | 10 | 10 | 10 |
| Comparative example 2 | - | 40 | 30 | - | 10 | 10 | 10 |
| Comparative example 3 | Oxygen-permeable hard contact lens A (Polymer comprising methacrylate ester having siloxane group and methyl methacrylate as main ingredients) | ||||||
| Comparative example 4 | Oxygen-permeable hard contact lens B (polymer comprising silicon-containing styrene derivative and fluoromethyl methacrylate as main ingredients) for continuous use | ||||||
TABLE 3
| Diameter (mm) | Basic camber (mm) | Degree (D) | Center thickness (mm) | |
| Example 1 | 8.8 | 7.75 | -3.00 | 0.080 |
| Example 2 | 8.8 | 7.75 | -3.00 | 0.090 |
| Example 3 | 8.8 | 7.75 | -3.00 | 0.100 |
| Example 4 | 8.8 | 7.75 | -3.00 | 0.100 |
| Example 5 | 8.8 | 7.75 | -3.00 | 0.100 |
| Example 6 | 8.8 | 7.75 | -3.00 | 0.100 |
| Example 7 | 8.8 | 7.75 | -3.00 | 0.100 |
| Example 8 | 8.8 | 7.75 | -3.00 | 0.100 |
| Comparative example 1 | 8.8 | 7.75 | -3.00 | 0.150 |
| Comparative example 2 | 8.8 | 7.75 | -3.00 | 0.150 |
| Comparative example 3 | 8.8 | 7.75 | -3.00 | 0.110 |
| Comparative example 4 | 9.2 | 7.75 | -3.00 | 0.130 |
TABLE 4
| Vickers hardness | Dk*1 | Dk/L*2 | Compression modulus of elasticity (gf) | Compressive bending Strength (gf) | Durability (times) | |
| Example 1 | 8.5 | 53 | 66 | 20 | 200 | 1000 |
| Example 2 | 8.5 | 53 | 59 | 24 | 240 | 1000 |
| Example 3 | 8.5 | 53 | 53 | 45 | 250 | 1000 |
| Example 4 | 7.5 | 66 | 66 | 34 | 230 | 1000 |
| Example 5 | 8.9 | 47 | 47 | 47 | 350 | 1000 |
| Example 6 | 8.9 | 60 | 60 | 45 | 215 | 1000 |
| Example 7 | 9.5 | 51 | 51 | 83 | 375 | 800 |
| Example 8 | 9.9 | 55 | 55 | 85 | 320 | 800 |
| Comparative example 1 | 8.5 | 53 | 35 | 120 | 380 | 400 |
| Comparative example 2 | 9.5 | 51 | 34 | 150 | 250 | 300 |
| Comparative example 3 | 11.7 | 12 | 11 | 40 | 370 | 1000 |
| Comparative example 4 | 7.4 | 250 | 192 | 120 | 120 | 100 |
(Note)
*1: oxygen permeability coefficient, unit: x 10-11cm3·cm/cm2·sec·mmHg
*2: oxygen permeability, unit: x 10-9cm3·cm/cm2·sec·mmHg·cm
As can be seen from the results shown in tables 2 to 4, the steel sheet has an oxygen permeability coefficient of 20X 10-11cm3·cm/cm2The oxygen permeable hard contact lenses of examples 1 to 8, which are made of a polymer having a center thickness of 0.010 to 0.125mm or more and a value of the refractive power at the apex of-6.00D or more, can withstand repeated stress of 800 times or more, and can obtain an oxygen permeability of 30X 10 times or more as required for daily use than that of mounting-9cm3·cm/cm2Sec mmHg cm.
In contrast, comparative examples 1 and 2, in which the center thickness of the lens was outside the range of the present invention, were significantly inferior in durability.
In addition, comparative example 3, in which the oxygen permeability coefficient was outside the range of the present invention, was significantly lower than the oxygen permeability of 30X 10 required for installation and use throughout the day-9cm3·cm/cm2·sec·mmHg·cm。
Further, comparative example 4, in which the center thickness of the lens was outside the range of the present invention, was low in the compressive bending strength and remarkably poor in the durability.
Industrial applicability
According to the present invention, an oxygen-permeable hard contact lens which can supply physiologically sufficient oxygen to the cornea and is excellent in durability is provided.
Claims (5)
1. An oxygen-permeable hard contact lens having a value of the refractive power at the apex of the lens of-6.00D or more, characterized by containing an oxygen permeability coefficient of 20 x 10-11cm3·cm/cm2Sec mmHg or more and a center thickness of the lens is 0.010 to 0.125 mm.
2. The oxygen permeable hard contact lens of claim 1, the polymer comprising monomeric units having a siloxane group.
3. The oxygen permeable hard contact lens of claim 1, the polymer comprising monomeric units having a siloxane group and monomeric units having a fluorine atom.
4. The oxygen-permeable hard contact lens of claim 2 or 3, wherein the monomeric units having a siloxane group are (meth) acrylamide units having a siloxane group.
5. The oxygen-permeable hard contact lens according to any one of claims 1 to 4, which has a Vickers hardness of 5 to 15 and a compression modulus of elasticity of 10 to 100 gf.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP311107/2001 | 2001-10-09 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| HK1069211A true HK1069211A (en) | 2005-05-13 |
Family
ID=
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP1197782B1 (en) | Material for ocular lens | |
| EP1235866B1 (en) | Soft contact lenses | |
| JP2011522934A (en) | Silicone-containing copolymer-based hydrogels | |
| JPWO1991010155A1 (en) | Contact lens materials and contact lenses | |
| JPWO2001071415A1 (en) | Ophthalmic lens materials | |
| EP0288567A1 (en) | Material for oxygen-permeable hard contact lens with excellent impact resistance | |
| JPH11287971A (en) | Ophthalmic lens materials | |
| JPS628769B2 (en) | ||
| EP0940414B1 (en) | Ocular lens material and process for producing the same | |
| JP4772939B2 (en) | Polymerizable monomer composition and contact lens | |
| EP0722110B1 (en) | Water absorptive soft contact lens | |
| JP7243733B2 (en) | Monomer composition for contact lenses, polymer for contact lenses, contact lenses and method for producing the same | |
| CN1537249A (en) | Oxygen Permeable Hard Contact Lenses | |
| WO2001023945A1 (en) | Ocular lens material | |
| HK1069211A (en) | Oxygen-permeable hard contact lens | |
| KR20240003019A (en) | Silicone hydrogel contact lenses | |
| JP3118389B2 (en) | Water-containing ophthalmic lens material | |
| JPH08334732A (en) | Soft contact lens | |
| JP2518984B2 (en) | Contact lens material and contact lens | |
| JP2926804B2 (en) | Soft contact lens | |
| JP2532405B2 (en) | High oxygen permeability hard contact lens | |
| KR20250170937A (en) | Hydrogel contact lens composition | |
| JPH09146052A (en) | Hydrous eye lens material | |
| KR20170050475A (en) | Silicone hydrogel composition for contact lens and contact lens produced using thereof | |
| JP2831127B2 (en) | contact lens |