JPS6339046B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention provides a polymer shape comprising at least a portion of a hydrophilic polymer, particularly a prosthesis or alternative that can be used effectively in aqueous environments where stress and distortion due to the absorption of water into the polymer matrix must be minimized. Pertains to prosthetic devices, that is, artificial devices that replace parts of the organs and tissues of the human body. The present invention further relates to a contact lens that has a step or change in physical properties from its center to its periphery, and a method for manufacturing the same. The present invention also particularly relates to a new contact lens having a relatively hard central portion and a soft hydrophilic periphery. The present invention further relates to polymers, particularly hydrophilic polymers suitable for making contact lenses and other alternative devices. Various hydrophilic materials have been proposed for use in alternative devices, particularly plastic contact lenses. Hydrogels formed from materials such as hydroxyalkyl methacrylates containing hydrophilic groups with affinity for water and aqueous solvents, which are given a slightly cross-linked hydrogel structure, have been used to make this type of lens. .
However, soft jelly-like viscoelasticity (elastic
Contact lenses made from hydrogels that have a high consistency are known to be difficult to apply and remove from the eye. Removal of this type of lens from the eye requires forceful movements, which sometimes results in scratching and abrasion. This is because conventional contact lenses adhere to the epithelium of the cornea rather than resting on the lachrymal layer of the cornea of the eye, thus altering the metabolic outflow from the anterior chamber of the eye. Other hydrophilic plastic contact lenses have been proposed in which the hydrophilic polymers of the lens material include about 50 to about 95% by weight hydroxyalkyl acrylate or methacrylate and minor amounts up to about 35% by weight alkyl acrylate or methacrylate. and about 1 to 50% by weight of cross-linking monomers. Polymers made in this manner can be used as contact materials with improved water wetting properties, but are susceptible to brittle during the curing operations required for contact lens molding and cannot be polished well. Lenses made from this material deteriorate over time and use, becoming flattened or distorted, altering corrective power and other lens parameters. Lenses made of this material also dry quickly when left in the air and exhibit relatively low strength during processing after hydration. Contact lenses having a hard central portion and a relatively soft peripheral portion shaped to conform to the surface of the eye are also known. According to British Patent No. 1,045,065 for John Treveall Decal, the central lens is made of the usual materials used in conventional hard plastic lenses, such as acrylic plastic with high optical quality, and a soft polymer. It is proposed to surround the surrounding area. This patent shows that epoxy resins can be effectively used in lens materials. The surrounding materials are soft epoxy plastic, polyvinyl chloride, copolymer of vinyl chloride and vinyl acetate, ethylene,
Selected from polymers such as fluorinated copolymers of polyethylene. Attempts have been made to use a combination of prior art methods to provide contact lenses with a hard center and a soft periphery, but it has been found that hydration results in significant residual stress and resulting distortion. Even if the peripheral part of the lens is made of a known hydrophilic material conventionally used to make hydrophilic soft contact lenses and combined with the known hard contact lens material in the central part, an acceptable lens can be obtained. Nakatsuta. Hydration of this complex lens results in severe distortion and often complete separation. Similarly, other alternative devices, such as cardiovascular devices, intrauterine devices, valves, tubes, and other intracorporeal implants, have hydrophilic surfaces that adhere to the device, but the stress of hydration can cause the coating to crack. ,
It has been found to exhibit other defects due to non-uniform expansion or distortion due to water absorption. A principal object of the present invention is to provide an alternative device, such as a human organ tissue, constructed at least in part of a hydrophilic polymeric material that does not exhibit stress, strain, or swelling upon hydration. Another object of the present invention is to provide new hydrophilic polymers that do not stress, strain or swell even after polymerization and hydration. An object of the present invention is to provide a contact lens that has different physical properties in stages from its center to its periphery. Still other objects of the invention are soft, hydrophilic, high strength after hydration, no deterioration over time, and relatively low release of hydrated water when exposed to air. The object of the present invention is to provide a new polymer having excellent properties for manufacturing contact lenses, such as slowness, excellent optical properties, excellent abrasiveness, and ease of manufacturing contact lenses. Yet another object of the present invention is to provide a means for relieving stress and strain in affinity polymers when immersed in water. A particular object of the present invention is to provide a contact lens having a relatively hard center and soft periphery to minimize or eliminate stress and distortion due to polymer hydration. The present invention provides a new type of alternative device and a new composition of materials for use in the manufacture of this type of device, especially contact lenses and other hydrophilic polymer structures used in aqueous environments where very large distortions are not tolerated. There is something to do. Contact lenses or other alternative devices provided by the present invention are characterized by their hardness, color, density, water absorption, photochromicity, light transmittance,
It has a gradual change in properties such as opacity, refractive index, and partial coloration without any residual stress or distortion due to hydration of the hydrophilic polymer used. The peripheral portion of the lens is a hydrophilic copolymer made from water-soluble vinyl monomers copolymerized with hydrophilic water-insoluble monomers in the presence of a cross-linking agent and a water-soluble inert material. The inert materials are substantially removed by contacting the polymer with water. When it is contacted with water, a significant portion of the water-soluble inert material is removed from the polymer matrix, resulting in a soft hydrophilic polymer structure suitable for use as a water-substituted contact lens. Lens stress and distortion can be minimized or eliminated simply by replacing the water-soluble inert material in the polymer matrix with water. The center of the contact lens has a different composition.
The physical properties of the lens can be changed in stages. The central portion is composed of a relatively hard polymer such as an extensively cross-linked copolymer of methoxyethyl methacrylate and hydroxyethyl methacrylate in combination with a cross-linking agent. The proportions of these compositions are appropriately selected so that the central portion is harder than the peripheral portion. One method of making the contact lenses of the present invention is to make a rod-shaped center member of polymer, for example about 6 to 7 millimeters in diameter. Relatively hard copolymers are commonly chosen as the central polymer system of contact lenses. A cylindrical periphery made of a hydrophilic polymer having lower hardness is formed around the outer periphery of the rod-like member to blend in with the central portion. A suitable water-soluble inert material that does not affect the polymerization is dissolved throughout the polymeric matrix used to form the outer periphery of the rod. This water-soluble inert material is intended to eliminate or minimize stress and strain due to hydration of the hydrophilic polymer when in contact with water. One method of forming a plurality of contact lenses of the present invention having graded properties from the center to the peripheral edge includes a first contact lens having a first set of properties.
A rod-like member is formed from a polymeric material and at least one layer of a second polymeric material is polymerized around the rod-like member. wherein the second polymeric material has a second set of properties, including being relatively softer than the rod, and comprising a hydrophilic polymer that is water-swellable and compatible with the rod. . Furthermore, said one layer comprises a water-soluble solid inert material. The composite rod-shaped member thus formed is cut into rings to form a plurality of contact lens blanks, each of these blanks is polished,
Create contour lenses. The lens can then be hydrated to remove the water-soluble solid inert material and replace it with water, creating a plurality of composite lenses that are relatively free of stress and strain after hydration. In another method of forming contact lenses of the invention, rods having an outer diameter of, for example, 14 mm are made of a polymer containing a water-soluble inert material. A hole of the same size as the center of the lens is drilled in the center of this rod, and a polymer is formed in this hole to accommodate the surrounding material. The resulting composite rod has a concentric structure in which the central core and the outer periphery have different properties. If a gradual change in properties is desired, the molding process can be repeated as many times as desired. Each successive hole for filling then uses a drill of progressively smaller diameter. The fillers used are mixtures of monomers that result in polymers that have different properties from the neighboring polymers. For example, the inside is harder than the periphery and a hydrophobic polymer is used. Of course, polymers having various other desired physical properties can also be used. In manufacturing the above-mentioned composite rod-shaped blank,
One or more markings may be applied to identify the finished lens. For example, if you mark one of two lenses made for one patient,
It is common practice that this allows the patient to know whether the lens is for the left or right eye. By incorporating thin rods of colored or opaque material at the periphery of the compound rod or at other suitable locations, all lenses cut from blanks thus marked bear an identifying mark. It turns out. The rod may be of any material that is compatible with the polymer system used. For example, a thin carbon rod, a rod made of dacron or nylon, or a colored plastic resin, may be contacted with the other parts of the composite rod material, as long as it does not melt the monomer used or interfere with its polymerization. It can be used as long as it can be easily polished into a lens shape. In one preferred embodiment of the invention, the composite rod material used to make the contact lens consists of an inner rod of relatively hard polymer surrounded by a relatively soft hydrophilic material containing a water-soluble material. This water-soluble inert material is removed from the polymer matrix when the hydrophilic polymeric material absorbs water and becomes hydrated upon contact with water. This composite rod member allows a skilled optician to fabricate a variety of contact lenses using conventional techniques. Special lenses,
For example, cylinder type, myodisc,
Lenticulars, prismatic truncations and other special lenses can also be made. Although these lenses can be molded from known hard methyl methacrylate lens materials, they cannot be made, or are difficult to make, from conventional soft hydrophilic materials. Residual astigmatism is corrected by the fact that the relatively hard central portion does not conform to the shape of the cornea, but rather changes the outer surface of the cornea to the desired shape. The relatively soft peripheral area reduces discomfort even when the lens is placed in the eye. The composite structure can be designed to regulate fluid flow under the lens so that the lens maintains a comfortable fluid cushion that lubricates between it and the surface of the eye. One particular embodiment of a contact lens is graded in color or opacity from its center to its periphery, thereby varying the degree of transmission of light through the lens. A lens with a completely opaque center or a central lens that is translucent to light can be used in cases of strabismus or defects in one eye, blocking that eye from light or preventing it from seeing images, and preventing the other eye from seeing images. Useful for therapeutic purposes such as when using and strengthening the eye. The procedure currently used by ophthalmologists to correct this is to completely occlude the healthy eye with an eye patch, leaving only the recessive eye to work. This is done by placing an eye patch over the eye or a black shield over the glasses. This technique is impractical and visually undesirable when applied to children and young people who cannot understand the need for such a method. In a particular embodiment of the invention, a sharp or translucent periphery helps an ophthalmologist more easily assess the suitability of a contact lens than if the entire lens were opaque or black. Furthermore, completely black lenses look unsightly. Lenses with a colored opaque central part that is colored to match the other eye of the person using the lens can be used to reduce the unsightly appearance caused by obstructions in the central part above the patient's pupil. can. The embodiments shown in the drawings will be described in detail below. Note that the same numbers in the figures indicate the same parts. FIG. 1 is a sectional view of an eyeball fitted with a contact lens of the present invention. The eyeball generally includes a retina 10, an optic nerve 11, a crystalline lens 12, and a cornea 1, as shown in FIG.
4, the iris 19, the anterior chamber 20, the lower eyelid 13, and the upper eyelid 15. The contact lens of the present invention has its central portion 16 made of a polymeric material that has various properties that make it suitable for specific uses, as described below. Peripheral portion 18 is joined to central portion 16 and is made of a polymeric material having properties different from those of central portion 16 . This will also be discussed later. The central portion 16 of the lens shown in FIG. 1 has a diameter sufficient to cover the aperture consisting of the iris 19 and substantially contacts the spherical portion of the cornea. The peripheral part 18 of the contact lens is polished on its inner side to a somewhat different radius of curvature than the central part 16, so that this peripheral part is similar to the peripheral part 21 of the cornea 14.
Adheres properly to the surface without peeling off. FIG. 2 is an enlarged sectional view of the lens shown in FIG. 1. The lens is shown constructed from a rod-shaped composite member having a central portion 36 and a peripheral portion 38. Central portion 36 is made of a polymeric material having a first set of properties. This portion of the rod consists of a water-soluble vinyl monomer that is homopolymerized or copolymerized with other monomers and cross-linking agents. The relative proportions of the composition of central portion 36 are selected to provide a polymeric composition with the set of physical properties desired for the intended particular field of use. Around the central portion 36, a water-insoluble hydrophilic monomer (water
There is a peripheral portion 38 consisting of a copolymer of a water-soluble vinyl monomer (insoluble, hydrophilic monomer), a cross-linking agent, and a water-soluble vinyl monomer. A water-soluble inert material is dispersed within this polymer matrix. The relative composition of the monomers is again chosen to have the set of physical properties desired for the particular intended application (field of use). Additional layers may then be polymerized around the outside of the composite rod if desired. This composite rod is cut into a suitable shape as shown in FIG. 2, and polished to form a composite lens structure as shown in the figure. Colorants, opacifiers or other additives may be added to one or more layers of the composite rod to alter the physical properties of the lens. In special situations, such as when severe damage has occurred to the iris or nearby ocular tissue, an artificial iris can be created by adding pigment to the periphery to block light transmission. Special tinting of lenses used for special purposes can also be achieved in this way. FIG. 3 shows another embodiment of the invention. In this embodiment, the physical characteristics gradually change from the center to the periphery. The lens in Figure 3 has its central part 4
0 is harder and the peripheral portion 42 is made of a softer polymer. This lens polymerizes a polymer system to the desired shape and then selectively irradiates certain portions of the polymer shape or other known methods of inducing cross-linking in the polymer system for further polymerization. is created by controlling the cross-linking that is then performed by the method. The complex lens described with reference to Figures 1 and 2 is made possible by adding a water-soluble inert substance to the monomer mixture before polymerization, so that when hydration takes place, no stress or strain is induced in the central part of the lens. 36
It has a characteristic that hydrophilicity and hardness change from the to the peripheral part 38. During the hydration process of hydrophilic polymers, the stress and distortion of the polymer shape can be reduced or eliminated by removing the water-soluble inert substances. If a more hydrophilic center portion 36 or a center portion that is only slightly harder than the peripheral portion 18 is desired, a smaller proportion of water-soluble material may be included in the polymer system utilized to form the center portion 36. In an attempt to mold a contact lens with a hard center and a soft periphery, it was found that conventional techniques and material compositions were not capable of molding the lens. Several attempts have been made without success, as outlined below. In the following, percentages are weight percentages. In an attempt to mold a lens with a hard center and a soft periphery, 60% methoxyethyl methacrylate and 20% 1,5-divinyloxy-3-oxapentane were mixed with azobis in a nitrogen-filled polyethylene tube. Isobutyronitrile (hereinafter
AlBN) was copolymerized with 38% hydroxyethyl methacrylate as a catalyst. The polyethylene tube was heated to 40°C and maintained at this temperature for 30 minutes. The resulting rod was cured at 60°C for 10 hours. This rod was then removed and cut to a diameter of 7 mm. 20% methoxyethyl methacrylate and
77% hydroxyethyl methacrylate and 2%
1,5-divinyloxy-3-oxapentane and 1% AIBN were polymerized for 30 hours at 40° C. with nitrogen surrounding the molded rod.
The composite rod was then further cured at 60°C for 10 hours. Lenses were cut from this material and soaked in distilled water for hydration. The lens became flattened and the edges became distorted. The curvature of the periphery changed considerably compared to the curvature before hydration. This lens was rejected as a defective product due to severe distortion, stress and changes in lens parameters due to the absorption of water by the hydrophilic polymer matrix. 30-70% ethoxyethyl methacrylate, 2
% of the cross-linker and the remainder consisting of hydroxyethyl methacrylate;
Several other attempts have been made to make lenses using a composite material consisting of 95% hydroxyethyl methacrylate, 2% cross-linker and a periphery in which the balance is methoxyethyl methacrylate and a catalyst of AIBN. However, the desired substance could not be obtained. Some of the lenses made in this manner failed upon hydration, and the remaining lenses exhibited unacceptable distortion. When used as a homogeneous polymeric material in soft hydrophilic lenses, this material showed substantially improved properties over conventional materials in terms of ease of molding, polishing, and stability in use; Hard due to distortion due to hydration.
It turned out that it could not be applied as a soft contact lens. By adding water-soluble substances into the polymer matrix before hydration, acceptable lenses can be made by preventing distortion and stress in the polymer matrix during this hydration. Ta. The following example demonstrates the success in making composite contact lenses from hydrophilic polymeric materials in the laboratory. Example: Crosslinking of methoxyethyl methacrylate (40%) and hydroxyethyl methacrylate (58%) crosslinked using 2% of 1,5-divinyloxy-3-oxapentane as a crosslinking agent and copolymerized using AIBN as a catalyst. A 7 mm diameter rod of bonded copolymer was made as described above. A mixture of 30% polyoxyethylene glycol, 15.5% methoxyethyl methacrylate and 2% 1,5-divinyloxy-3-oxapentane as catalyst.
It was copolymerized around the previously formed rod in the presence of 1% AIBN. This mixture was polymerized at 40°C for 30 hours and then cured at 60°C for 10 hours. A composite rod with a diameter of 14 mm was cut into many cylindrical pieces.
I started making contact lenses. Even after hydration, a hard-soft lens was obtained in which no distortion occurred in the radius of curvature obtained by polishing before hydration. These lenses had a ratio of hardness at the center to hardness at the periphery of 2:1. Example: 40% polyoxyethylene glycol around a 6 mm rod of a cross-linked copolymer of methoxyethyl methacrylate (95%) and hydroxyethyl methacrylate (2%) cross-linked with 3% ethylene glycol dimethyl acrylate. , 12% methoxyethyl methacrylate, 46%
A mixture of hydroethyl methacrylate and 1.5% ethylene glycol dimethyl acrylate was polymerized using 0.5% AIBN as a catalyst at 42°C for 24 hours. The resulting composite rod was cured at 60°C for 12 hours. I made this material into a rod and made lenses from it. Once hydrated, the lens now has a relatively hard center and a soft periphery. The ratio of hardness in the central part to hardness in the peripheral part was approximately 20:1. No strain or stress was observed in the soft periphery. Examples Methoxyethyl methacrylate (20%), hydroxyethyl methacrylate (78%) and 1,
5-divinyloxy-3-oxapentane (2
%) of a cross-linked copolymer (diameter 6 mm), in a mixture of polyoxyethylene glycol (10%) and methoxyethyl methacrylate (81%), 2 g of 1,5- Adding 0.5 g of AIBN per 100 g of divinyloxy-3-oxapentane and the above mixture, 45
Polymerization was carried out at ℃ for 48 hours. The resulting composite rod was cured at 60°C for 10 hours. This compound rod has a diameter
I made a 14mm lens. When hydrated, the ratio of center hardness to peripheral hardness is 1.06:1.
A soft lens was obtained. No distortion or stress was observed in this lens either at the center or at the periphery. Examples Methoxyethyl methacrylate (20%), hydroxyethyl methacrylate (76.5%), 1,5
-divinyloxy-3-oxapentane and allylamine and reactive dyes (ICIAmerica's
Cross-linked copolymer rod (diameter 6 mm) of monomers obtained from Procion Brilliant Blue)
around polyoxyethylene glycol (10
%), methoxyethyl methacrylate (9%), and hydroxyethyl methacrylate (81%) with 2 g of 1,5-
Similarly to divinyloxy-3-pentane, 0.5 g of AIBN per 100 g was added and polymerized at 45°C for 48 hours. The resulting composite rod was cured at 60°C for 10 hours. A lens was made from this material with a diameter of 14 mm.
When hydrated, the ratio of hardness in the center to hardness in the periphery increases.
A hard-to-soft lens ratio of 1.09:1 was obtained. No distortion or stress was observed in either the center or the periphery of the lens. The center of the lens was transparent blue, and the periphery was colorless. Example The same lens as described in Example was made.
However, the mixture to be polymerized contained 1.5 g of monomer obtained from allylamine and a reactive dye (Procion dye Brillant Blue) per 100 g of said mixture. The resulting lens was clear and colorless in the center, colored in the periphery, and had no stress or distortion. EXAMPLE A lens having a hydrophobic center and a soft hydrophilic periphery was made according to the steps in Example above. However, the central 6 mm rod was made from ethylene glycol dimethacrylate (1%) and methyl methacrylate (99%) polymerized. The resulting lenses had a hard center and a soft periphery with no stress or strain, and the center exhibited greater fluid circulation due to its hydrophobic nature. Example 2-hydroxyethyl methacrylate (56%),
Methoxyethyl methacrylate (14%) and polyoxyethylene glycol molecular weight 6000 (30%)
of the same mixture with 2 g of 1,5-divinyloxy-3-oxypentane per 100 g of the mixture.
Polymerization was carried out at 42°C for 24 hours using 0.5g of AIBN per 100g as a catalyst, and the material was further cured at 60°C for 10 hours to form a 14 mm rod. Drill a 6 mm hole in the center and fill this hole with 2-hydroxyethyl methacrylate (58%) and methoxyethyl methacrylate (40%).
%) and 1,5-divinyloxy-3-oxapentane (2%).
It was added with 0.5g of AIBN per plate and cured at 40°C for 24 hours. Lenses were made by cutting this material. When hydrated, this lens had a hard center to soft peripheral hardness ratio of 2 to 1 based on water content. Examples Methyl methacrylate (40%), 2-hydroxyethyl methacrylate (58%) and 1,5-
2-hydroxyethyl methacrylate (56
%), methyl methacrylate (14%) and polyethylene glycol molecular weight 6000 (30%), and 2 g of 1,5-divinyloxy-3-oxapentane per 100 g of this mixture and 1.0 g of 1,5-divinyloxy-3-oxapentane per 100 g of this mixture.
Polymerized using AIBN as a catalyst at 40℃ for 48 hours,
It was further cured at 60°C for 10 hours. Lenses were cut from the resulting material. Upon hydration, the lens became a hard-soft lens with a hardness ratio of 15:1 in the center and periphery based on water content. It has been found that the ratio of hardness between the central part and the peripheral part can be varied from 1:1 to 50:1 by changing the material of each part. Suitable compositions of the center and periphery may vary within the following ranges to provide acceptable properties of a relatively stiff center surrounded by a hydrophilic periphery.

[Table] In the above, all percentages are weight percentages. Examples of water-soluble vinyl monomers that can be used are as follows, although their effects vary. 1 Hydroxyalkyl methacrylates and acrylates containing alkyl groups having 2 to 6 carbon atoms 2 Vinyl hydroxy acetate, vinyl hydroxy propionate, vinyl hydroxy butyrate 3 N-vinyl lactam, i.e. N- vinyl pyrrolidone, N- vinyl caprolactam and N - Vinylpiperidone 4 N,N dialkylaminoethyl methacrylates and acrylates containing alkyl groups having 0 to 2 carbon atoms 5 Hydroxyalkyl vinyl ethers containing alkyl groups having 2 to 4 carbon atoms 6 1-Vinyloxy 2- Hydroxyethylene, 1-vinyloxy 5-hydroxy 3-oxapentane, 1-vinyloxy 8-hydroxy 3,6-dioxaoctane, 1-vinyloxy 11-hydroxy 3,6,9-trioxanedecane and 1- Vinyloxy 14-hydroxy 3,6,9,12tetraoxatetradecane 7 N-vinylmorpholine 8 N,N dialkylacrylamide containing an alkyl group having 0 to 2 carbon atoms 9 Containing an alkyl group having 1 to 2 carbon atoms Alkyl vinyl ketone 10 N-vinyl succinimide and N-vinyl glutarimide 11 N-vinyl imidazole 12 N-vinyl 3-morpholinone Along with the water-soluble vinyl monomers mentioned above, there are also water-insoluble hydrophilic monomers that can be used, although the effects vary. Examples of monomers are as follows. 1 Methoxyethyl and ethoxyethyl acrylate and methacrylate 2 Vinyl methoxyacetate, propionate and butyrate 3 Vinyl ethoxyacetate, propionate and butyrate 4 Mesoxyalkyl and alkoxyalkyl vinyl ethers containing alkyl groups with 1 to 4 carbon atoms The above-mentioned Examples of water-soluble inert materials that are compatible with the monomers and polymers and to be incorporated into the polymer matrix are listed below. 1 Polyoxyethylene glycol, polyoxypropylene glycol, with a molecular weight of 1100 to 100000,
Polyoxybutylene glycol 2 Benzotic acid, druitsuic acid, napsoic acid 3 Esters and ethers of polyoxyethylene glycol, polyoxypropylene glycol and polyoxybutylene glycol with a molecular weight of 1000 to 100000 4 Soaps and surfactants 5 Polyvinyl pyrrololidone, poly Vinyl caprolactam, polyvinyl piperidone 6 N-acetyl polyethyleneimine 7 poly-N-vinyl imidozole, poly-N
- Vinyl succinimide, poly-N-vinyl glutarimide Examples of suitable cross-linking agents for use are: 1 Vinyl acrylates and methacrylates 2 Allyl acrylates and methacrylates 3 Diacrylates and dimethacrylates of polyoxyethylene, polyoxypropylene and polyoxybutylene glycol 4 Triacrylates and trimethacrylates of glycerol 5 Triallyl cyanurate 6 Olefin glycol dimethacrylate 7 Allyl Diglycol carbonates 8 Triallyl sinurates 9 Diaryl carbonates and polyallyl carbonates of dihydroxy or polyhydroxy compounds 10 Divinyl and polyvinyl carbonates of dihydroxy or polyhydroxy compounds 11 Diacrylates or triacrylates and methacrylates of polyhydroxy compounds 12 Dicarboxylic acids or Divinyl or trivinyl esters of polycarboxylic acids13 Divinyl or trivinyl ethers of dihydroxy or polyhydroxy compounds14 Diallyl or triallyl ethers of dihydroxy or polyhydroxy compounds15 Diallyl or triallyl esters of dicarboxy or polycarboxy compounds A preferred catalyst that can be used in the above examples is axobisisobutyronitrile (axobisisobutyronitrile).
butyronitrile). Other catalysts that induce polymerization and cross-linking can also be used with varying effectiveness. For example, various organic peroxides such as benzoyl peroxide, chlorobenzoyl peroxide, tertiary butyl peroxide peroxycarbonate lauryl and many other peroxides that are soluble in the monomer system can also be used. Alternative devices made of composite polymers according to the present invention have been described with particular reference to standard type contact lenses. Contact lenses used for special purposes, such as lenses used as a means of treatment, can also be easily manufactured based on the technique of the present invention. Membrane contact lenses, corneal contact lenses, microlenses and special corrective lenses such as artificial irises, centrally or peripherally opaque lenses used in cases of albinism, ocular atrophy or other conditions are all included. It can be manufactured according to the present invention. Due to the hydrophilic periphery, any type of lens can be used without causing discomfort to the wearer, and because of the gradation of physical properties from one part of the lens to another, it is known to the contact lens industry. It has become possible to use it for a wide variety of purposes that were not previously available. Thus, the present invention provides alternative composite polymer devices including contact lenses, intracorporeal implants, cardiovascular devices, and other devices. These devices are intended for use in aqueous environments where strain and stress between the constituent elements must be minimized, and at least a portion of the device is made of hydrophilic polymers. There is. In a particular embodiment, the present invention provides a contact lens comprised of a foreign material, at least a portion of which is hydrophilic. In this part, stress and strain are minimized by adding to the hydrophilic matrix an amount of water-soluble material that is removed by contact with water, such as by hydration of the lens during use. has been done. The resulting lens has the comfort of a soft lens and the ability to correct vision.
It also has the visual accuracy of traditional hard plastic lenses. Below, embodiments of the present invention are listed. (1) It has a central part and a peripheral part that is in close contact with the central part, the central part is harder than the peripheral part, and the peripheral part is hydrophilic and compatible with the substance forming the central part. A contact lens that is made of polymer and has relatively little stress and distortion in the peripheral area. (2) the peripheral region contains a water-soluble inert substance dissolved in the polymer matrix before hydration;
The contact lens according to (1) above, wherein this substance is removed from the matrix during hydration of the hydrophilic polymer. (3) The above (1) in which the central portion is made of a hydrophilic polymer.
Contact lenses described in . (4) The central portion is made of a cross-linked copolymer of 30-90% by weight of a water-insoluble hydrophilic monomer, 10-70% by weight of a water-soluble vinyl monomer, and a small amount of a cross-linking agent up to 20% by weight. The contact lens according to (1) above. (5) The contact lens according to (2) above, wherein the inert substance is polyoxyethylene glycol. (6) The peripheral portion contains 10 to 95% by weight of hydroxyalkyl acrylate or methacrylate and 5
~90% by weight hydrophilic water-soluble monomer and 10% by weight
The contact lens according to (1) above, comprising a copolymer comprising a cross-linking agent up to and a small amount of a water-soluble agent up to 40% by weight completely dissolved in the copolymer. (7) said central portion comprises a crosslinked copolymer formed from 10 to 70% by weight hydroxyl methacrylate, 30 to 90% by weight methoxyethyl methacrylate, and up to about 20% by weight crosslinked monomer; The periphery contains 10-95% by weight of hydroxyethyl methacrylate, 5-90% by weight of methoxyethyl methacrylate, a small amount of cross-linked monomer up to 10% and a small amount of up to 40% by weight completely dissolved in the copolymer. a cross-linked copolymer consisting of a water-soluble agent of
Contact lenses described in (1). (8) a central rod-like member comprising a polymer having a first set of properties; at least one rod-like member polymerized around said central rod-like member and comprising a polymer having properties different from said first set of properties; A contact lens material comprising a hydrophilic polymer having an outer layer and a water-soluble agent dissolved in the polymer matrix of the outer layer. (9) The central rod-shaped member is made of a hydrophilic polymer having a water absorbency different from that of the outer layer and having a water-soluble agent dissolved in the polymer matrix in an amount substantially equal to the water absorption of the polymer. The contact lens material according to (8) above. (10) The contact lens material according to (8), wherein the central rod-shaped member is harder than the outer layer. (11) The contact lens material according to (8) above, which has identification means extending in the length direction of the material.

[Brief explanation of the drawing]

FIG. 1 is an enlarged vertical cross-sectional view of an eyeball wearing a contact lens of the present invention, FIG. 2 is a cross-sectional view showing one embodiment of the contact lens of the present invention, and FIG. 3 is another embodiment of the contact lens of the present invention. A sectional view showing an example. 16,40...Central part of contact lens, 1
8, 42... Peripheral area of contact lens.

Claims (1)

[Scope of Claims] 1. A contact lens consisting of a central lens portion and a peripheral skirt portion joined thereto, wherein the central lens portion has a greater hardness than the peripheral skirt portion; the peripheral skirt portion is hydrophilic and typically inflatable. comprising a polymer matrix that is water-based and compatible with the material forming the central lens portion; the peripheral skirt portion is relatively stress and strain free and is dissolved within the polymer matrix prior to hydration; a water-soluble solid inert material; this material is removed from the matrix during hydration of the hydrophilic polymer; a contact lens. 2 (i) consisting of (a) a relatively hard central portion; and (b) a relatively soft, water-swelling, hydrophilic polymer compatible with said central portion, and having a water-soluble solid inert substance therein; (ii) polishing said blank into a contact lens; and (iii) hydrating said lens to form said water-soluble solid inorganic material. A method of manufacturing a contact lens comprising the steps of removing the active substance and replacing it with water to produce a lens that is relatively stress and distortion free after hydration. 3. A method of manufacturing a plurality of contact lenses having graded properties from their center to their peripheral edges, comprising: (i) forming a rod-like member from a first polymeric material having a first set of properties; (ii) polymerizing at least one layer of a second polymeric material around the rod, wherein the second polymeric material is water-swellable, including being relatively softer than the rod; a second set of properties different from those of the first set, comprising a hydrophilic polymer compatible with the rod-shaped member;
the layer includes a water-soluble solid inert material dispersed therein; (iii) slicing the composite rod-like member to form a plurality of contact lens blanks; (iv) each of the blanks; and (v) hydrating said lens to remove said water-soluble solid inert material and replace it with water, resulting in a lens that is relatively free of stress and distortion after hydration. The method comprising the steps of: making;