KR20090015016A - Methods and systems for leaching and releasing silicone hydrogel ophthalmic lenses with surfactant solutions - Google Patents

Abstract

This invention includes methods and systems for processing hydrogel lenses using aqueous solutions as leaching aids and as release aids.

Description

Methods and systems for leaching and releasing silicone hydrogel ophthalmic lenses using surfactant solutions {Methods and systems for leaching and releasing silicone hydrogel ophthalmic lenses with surfactant solutions}

The present invention relates to a method for producing an ophthalmic lens made of silicone hydrogel. More specifically, the present invention relates to a method and system for leaching components from an ophthalmic lens and releasing the lens from a mold part in which the lens is cast.

It is well known that contact lenses can be used to improve vision. Various contact lenses have been commercially manufactured for many years. Early contact lenses were made of hard materials. Such lenses are still used in some applications today but are not suitable for all patients because of their poor fit and relatively low oxygen transmission. Since then, the art has developed soft contact lenses based on hydrogels.

Hydrogel contact lenses are very popular today. These lenses are often more comfortable to wear than contact lenses made of hard materials. Malleable soft contact lenses can be made by molding the lens in a multi-part mold in which the parts joined together form an overall shape that matches the desired final lens.

Multi-part moulds used to make hydrogels a useful product, such as ophthalmic lenses, are for example the first mold part with a convex surface corresponding to the back curve of the ophthalmic lens and the front curve of the ophthalmic lens. And a second mold part having a concave surface. In order to manufacture a lens using such a mold part, an uncured hydrogel lens composition is placed between the concave and convex surfaces of the mold part and then cured. The hydrogel lens composition can be cured by, for example, exposure to either or both of heat and light. The cured hydrogel forms a lens according to the dimensions of the mold part.

After curing, according to a typical embodiment, after separating the mold parts, the lens remains attached to one mold part. The release process removes the lens from the remaining mold part. The extraction step removes unreacted components and diluents (hereinafter referred to as "UCD") from the lens to affect the clinical life of the lens. If UCDs are not extracted from the lenses, they can worsen the fit of the lens.

According to the prior art, release of the lens from the mold can be easily performed by exposing the lens to an aqueous or salt solution such that the solution swells the lens and degrades the adhesion of the lens to the mold. Exposure to aqueous or salt solutions also serves to extract the UCD, making the lens more comfortable to wear and making the lens clinically acceptable.

The art has newly developed contact lenses made of silicone hydrogels. Known hydration methods using aqueous solutions for release and extraction are not effective for silicone hydrogel lenses. Thus, attempts have been made to release silicon lenses and remove UCDs using organic solvents. The lens is immersed in alcohol (ROH), ketone (RCOR '), aldehyde (RCHO), ester (RCOOR'), amide (RCONR'R ") or N-alkyl pyrrolidone in the absence of water for 20 to 40 hours. Or impregnated with a mixture containing water as a minor component (US Pat. No. 5,258,490).

However, although known methods have been somewhat successful, the use of highly concentrated organic solutions has disadvantages including, for example, safety risks, increased risk of production line interruption, expensive release solutions, and the possibility of secondary damage from explosions. Can have.

Thus, it would be advantageous to provide a method of making a silicone hydrogel contact lens that requires little or no organic solvent, no flammable reagents, effectively releases the lens from the lens molding mold and removes UCD from the lens. .

[Overview of invention]

Accordingly, the present invention provides a method for leaching UCD of a silicone hydrogel ophthalmic lens without immersing the lens in an organic solvent. According to the present invention, release of the silicone hydrogel lens from the mold in which the lens is molded is easily performed by exposing the lens to an effective amount of an aqueous solution of at least one surfactant. In addition, leaching of UCD from a lens is easily accomplished by exposing the lens to an effective amount of one or more solutions of surfactants.

Further, the present invention generally relates to ophthalmic lenses made of a material comprising a wet silicone hydrogel formed from a reaction mixture comprising at least one high molecular weight hydrophilic polymer and at least one hydroxyl functionalized silicone containing monomer. In some embodiments, the ophthalmic lens is formed from a reaction mixture comprising a high molecular weight hydrophilic polymer and an effective amount of hydroxyl functionalized silicone containing monomer.

In another aspect, the present invention relates to a method of manufacturing an ophthalmic lens comprising mixing a high molecular weight hydrophilic polymer with an effective amount of a hydroxyl functionalized silicone containing monomer to form a clear solution and curing the solution. Thus, some embodiments comprise (a) mixing a high molecular weight hydrophilic polymer with an effective amount of a hydroxyl functionalized silicone containing monomer and (b) curing the product of step (a) to form a biomedical device and the product of step (a) And curing to form the wettable biomedical device.

In some embodiments, the present invention is an ophthalmic formulation formed from a reaction mixture comprising a high molecular weight hydrophilic polymer and at least one hydroxyl functionalized silicone containing monomer in an amount sufficient to provide a lens with a forward contact angle of less than about 80 degrees to the lens without surface treatment. It relates to a lens.

It has been found that the lens can be released from the cured mold by exposing the cured silicone hydrogel ophthalmic lens to an effective amount of an aqueous solution of release aid. It has also been found that leachable materials can be properly removed from the lens by exposing the cured silicone hydrogel ophthalmic lens to an effective amount of an aqueous solution of leach aid.

Justice

As used herein, “appropriate removal of leachable materials” means that at least 50% of the leachable material is removed from the lens after treating the lens.

As used herein, “leachable material” includes UCD and other materials that are not bound to the polymer and can be extracted from the polymer substrate, for example by leaching with water or an organic solvent.

As used herein, a "leak aid" is any compound that can provide a lens from which an appropriate amount of leachable materials has been removed when used in an effective amount in an aqueous solution to treat an ophthalmic lens.

As used herein, a “monomer” is a compound that contains one or more polymerizable groups and has an average molecular weight of less than about 2,000 Daltons, as measured by gel permeation chromatography refractive index detection. The monomer may thus comprise dimers and in some cases oligomers (including oligomers made of two or more monomer units).

As used herein, the term "ophthalmic lens" refers to the device placed on the eye. These devices can provide optical correction, wound healing, drug delivery, diagnostic functions, cosmetic improvement effects, or a combination of these properties. Lenses include, without limitation, soft contact lenses, hard contact lenses, intraocular lenses, overlay lenses, ocular inserts, and optical inserts.

As used herein, a "release aid" reduces the time required to release the ophthalmic lens from the mold when combined with water, rather than the time required to release the lens using an aqueous solution that does not include the release aid. , Compounds or mixtures of compounds except organic solvents.

As used herein, "releasing from a mold" means that the lens is completely detached from the mold, or loosely attached so that it can be detached by gently shaking or pushing it with a cotton swab.

As used herein, the term “treatment” means exposing the cured lens to an aqueous solution comprising one or more leach aids and release aids.

As used herein and defined above, the term "UCD" refers to unreacted components and diluents.

process

According to the present invention, the treatment may comprise exposing the cured lens to an aqueous solution containing one or more leach aids and release aids. In various embodiments, the treatment can be accomplished, for example, by impregnating the lens in solution or exposing the lens to a flow of solution. In addition, in various embodiments the treatment may be performed to, for example, heat the solution, stir the solution, increase the concentration of the release aid in the solution to a level sufficient to release the lens, mechanically stir the lens, and properly remove UCD from the lens. It may also include increasing the concentration of leaching aid in solution to a sufficient level.

By way of non-limiting example, various implementations involve a batch process in which the lens is immersed in a solution in a fixed tank for a specific time, or by a vertical process in which the lens is exposed to a continuous flow of a solution containing one or more leach aids and release aids. Release and UCD removal can be achieved.

In some embodiments, the solution may be heated using a heat exchanger or other heating device to further facilitate leaching of the lens and release of the lens from the mold part. For example, the solution can be heated by raising the temperature of the aqueous solution to the boiling point while immersing the hydrogel lens and the molded part to which the lens is adhered in the aqueous solution. Another aspect may include controlled circulation of the aqueous solution temperature.

In some embodiments, physical agitation may be used to facilitate leaching and release. For example, the lens mold component to which the lens is bonded may vibrate or cause movement back and forth in an aqueous solution. Another aspect may include ultrasound through an aqueous solution.

These and other similar processes can provide an acceptable means of releasing the lens and removing the UCD from the lens prior to packaging.

Variant

According to the invention, release of the silicone hydrogel lens is easily carried out by treating the lens with a solution containing one or more release aids combined with water at a concentration effective to release the lens. In some embodiments release can be readily performed by a release solution that expands the silicone hydrogel lens by at least 10% (expansion = diameter of lens in release aid solution / diameter of lens in borate buffered saline × 100).

In some embodiments, the release aid may include an alcohol, such as, for example, a C ₅ to C ₇ alcohol. Alcohols useful as release aids in some embodiments may include primary, secondary and tertiary alcohols having 1 to 9 carbons. Examples of such alcohols are methanol, ethanol, n-propanol, 2-propanol, 1-butanol, 2-butanol, tert-butanol, 1-pentanol, 2-pentanol, 3-pentanol, 2-methyl-1 Butanol, tert-amyl alcohol, neopentyl alcohol, 1-hexanol, 2-hexanol, 3-hexanol, 2-methyl-1-pentanol, 3-methyl-1-pentanol, 4-methyl- 1-pentanol, 2-methyl-2-pentanol, 3-methyl-2-pentanol, 3-methyl-3-pentanol, 1-heptanol, 2-heptanol, 3-heptanol, 4-heptane Ol, 1-octanol, 2-octanol, 1-nonanol, and 2-nonanol. In some embodiments, phenol is also available.

In addition, in some embodiments of the present invention, leaching aids, discussed further below, may be combined with alcohols to improve release rates. In some embodiments, leach aids can be used as release aids without the addition of alcohol. For example, leaching aids are used at concentrations greater than about 12%, or used to release the lens with a water soluble diluent such as tert-amyl alcohol.

Lens material

Ophthalmic lenses suitable for use in the present invention include those made of silicone hydrogels. Silicone hydrogels offer advantages to wearers of ophthalmic lenses over conventional hydrogels. For example, they typically provide a much higher oxygen transmission rate Dk, or oxygen transfer rate Dk / l, where l is the thickness of the lens. Such lenses have less corneal edema due to reduced oxygen deficiency, less corneal limbus, better fit and less risk of side effects such as bacterial infections. Silicone hydrogels are typically prepared by combining silicone containing monomers or macromonomers with hydrophilic monomers or macromonomers.

Examples of silicone-containing monomers include SiGMA (2-propenoic acid, 2-methyl-2-hydroxy-3- [3- [1,3,3,3-tetramethyl-1-[(trimethylsilyl) oxy] disiloxane Sanyl] propoxy] propyl ester), α, ω-bismethacryloxypropylpolydimethylsiloxane, mPDMS (monomethacryloxypropyl terminated mono-n-butyl terminated polydimethylsiloxane) and TRIS (3-methacryloxy Propyltris (trimethylsiloxy) silane).

Examples of hydrophilic monomers include HEMA (2-hydroxyethyl methacrylate), DMA (N, N-dimethylacrylamide) and NVP (N-vinylpyrrolidone).

In some embodiments, the high molecular weight polymer can be added to the monomer mixture to perform the function of the internal wetting agent. In some embodiments, additional ingredients or additives generally known in the art may be included. Additives may include, for example, ultraviolet absorbing compounds and monomers, reactive colorants, antimicrobial compounds, pigments, photochromic materials, release agents, and combinations thereof.

Silicone monomers and macromonomers are combined with hydrophilic monomers or macromonomers and introduced into an ophthalmic lens mold and cured by exposing the monomers to one or more conditions that may cause polymerization of the monomers. Such conditions include, for example, heat and light, which may include visible light, ion light, actinic radiation, X-rays, electron beams or ultraviolet (“UV”) light. In some embodiments, the light used to cause the polymerization may have a wavelength of about 250 to about 700 nm. Suitable radiation sources include UV lamps, fluorescent lamps, incandescent lamps, mercury vapor lamps, and sunlight. In embodiments in which the UV absorbing compound is included in the monomer composition (eg as a UV blocker), curing may be performed by means other than UV irradiation (eg, visible light or heat).

In some embodiments, the radiation source used to promote curing can be selected at low intensity from UVA (about 315 to about 400 nm), UVB (about 280 to about 315 nm) or visible light (about 400 to about 450 nm). have. In some embodiments, a mixture comprising a UV absorbing compound may be used.

In some embodiments in which heat is used to cure the lens, a thermal initiator can be added to the monomer mixture. Such initiators may include one or more of peroxides such as benzoyl peroxide and azo compounds such as AIBN (azobisisobutyronitrile).

In some embodiments, UV or visible light can be used to cure the lens and add photoinitiators to the monomer mixture. Such photoinitiators may include, for example, aromatic alpha-hydroxy ketones, alkoxyoxybenzoins, acetophenones, acyl phosphine oxides, and tertiary amines and diketones, and mixtures thereof. Representative examples of photoinitiators include 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, bis (2,6-dimethoxybenzoyl) -2,4,4- Trimethylphenyl phosphine oxide (DMBAPO), bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide (Irgacure 819), 2,4,6-trimethylbenzyldiphenyl phosphine oxide and 2 , 4,6-trimethylbenzoyl diphenylphosphine oxide, benzoin methyl ester, and a combination of camphorquinone and ethyl 4- (N, N-dimethylamino) benzoate. Commercially available visible light initiators include Irgacure 819, Irgacure 1700, Irgacure 1800, Irgacure 819, Irgacure 1850 (Ciba Specialty Chemicals) and Lucirin TPO initiators (manufacturer: BASF). Commercially available UV photoinitiators include Darocur 1173 and Darocure 2959 (Ciba Specialty Chemicals).

In some embodiments it may also be useful to include diluents in the monomer mixture, for example to improve the solubility of the various components, or to increase the degree of polymerization or transparency of the polymer to be produced. Examples of diluents may include secondary or tertiary alcohols.

Various methods are known for processing the reaction mixture in the manufacture of ophthalmic lenses, including known centrifugal casting and stationary casting. In some embodiments, a method of making an ophthalmic lens from a polymer includes molding silicone hydrogels. Silicone hydrogel molding is efficient and allows precise control of the final shape of the hydration lens.

The process of molding the ophthalmic lens from the silicone hydrogel may include introducing the metered monomer mixture into the concave mold part. The convex mold part is then placed on top of the monomer and compressed to form a closed cavity that defines the shape of the contact lens. The monomer mixture inside the mold part is cured to form a contact lens. Wherein curing of the monomer mixture includes processes or conditions that allow or promote polymerization of the monomer mixture. Examples of conditions that promote polymerization include one or more of light exposure and application of thermal energy.

After separating the half molds, the lens is typically glued to either half mold. Physical detachment of the lens from such a half mold is generally difficult, and generally the half mold is placed in a solvent to release the lens. Expansion of the lens, which occurs when the lens absorbs some of the solvent, typically promotes release of the lens from the mold.

Silicone hydrogel lenses can be made using relatively hydrophobic diluents such as 3,7-dimethyl-3-octanol. If such a lens is to be released in water, the diluent interferes with the absorption of water and does not allow sufficient expansion for release of the lens.

Alternatively, silicone hydrogels may be prepared using relatively hydrophilic water-soluble diluents such as ethanol, tert-butanol or tert-amyl alcohol. If such diluents are used and lenses and molds are placed in water, the diluents can be more easily dissolved and the lenses can be released more easily in water than with hydrophobic diluents.

Leachable Material

The polymer formed after the lens has cured typically contains a small amount of material that is not bound or incorporated into the polymer. Leachable materials that are not bound to the polymer (hereinafter “leachable materials”) can be extracted from the polymer substrate, for example by leaching with water or organic solvents. Such leachable materials can adversely affect the use of contact lenses in the eye. For example, the leachable material may be slowly released from the contact lens when the contact lens is worn on the eye, causing irritation or a toxic effect on the wearer's eye. In some cases, the leachable material may form a hydrophobic surface on the surface of the contact lens or attract debris from tears to cloud the lens surface and may interfere with the wetting of the lens.

Some materials may be physically trapped in the polymer matrix and they may not be removed by, for example, extraction with water or organic solvents. Here, the collected material is not considered a leachable material.

Leachable materials typically include most or all of the materials included in monomer mixtures that do not have polymerization functionality. For example, the diluent may be a leachable material. Leachable materials may also include nonpolymerizable impurities present in the monomers. As the polymerization is completed, the polymerization rate will typically be slow and some minor monomers may not be polymerized. Unpolymerized monomers may be included in the material to be leached from the polymerized lens. Leachable materials may also include small polymer fragments, or oligomers. The oligomer may be generated from the termination reaction initially in the formation of any given polymer chain. Thus, leachable materials may include any or all mixtures of the components described above, which may differ in properties such as toxicity, molecular weight or water solubility.

Leaching aids

In accordance with the present invention, leaching of silicone hydrogel lenses is readily performed by exposing the lens to a solution containing one or more leaching aids combined with water at a concentration effective to remove UCD from the lens.

For example, in some embodiments, treatment may be performed to expose the ophthalmic lens to a leaching aid and a GC mass spectrometer may be used to determine the concentration of one or more UCDs present in the ophthalmic lens. The GC mass spectrometer can determine whether treatment with a particular leaching aid is effective to reduce the amount of a particular UCD present in the lens to the maximum threshold amount.

Thus, in some embodiments, a GC mass spectrometer can be used to determine the maximum threshold (approximately 300 ppm) of UCDs such as SiMMA, mPDMS, SiMMA glycol, and epoxide. The minimum hydration treatment time required to reduce the amount of such UCD present in a particular lens to 300 ppm or less can be determined by periodic measurements. In further embodiments, other UCDs or other diluents, such as, for example, D3O, may be measured to detect the presence of a maximum amount of approximately 60 ppm. Some aspects may also include setting a threshold amount of a particular UCD to the minimum level of detection identifiable by the testing device.

According to the present invention, examples of leaching aids include ethoxylated alcohols or ethoxylated carboxylic acids, ethoxylated glucosides or sugars optionally bonded with C8 to C14 carbon chains, polyalkylene oxides, sulfates, carboxylates or amines of C8 to C10 compounds. Oxides are included. Examples are cocoamidopropylamine oxide, C _12-14 fatty alcohols ethoxylated with 10 ethylene oxides, sodium dodecyl sulfate, polyoxyethylene-2-ethyl hexyl ether, polypropylene glycol, polyethylene glycol monomethyl ether, ethoxy Silylated methyl glucoside dioleate, and sodium salt of n-octyl sulfate, sodium salt of ethylhexyl sulfate.

The following examples are described to illustrate the present invention. These examples do not limit the invention. These are merely for the purpose of presenting a method of practicing the present invention. Those skilled in the art of contact lenses and other techniques may find other methods of practicing the present invention, which are deemed to be within the scope of the present invention.

High molecular weight hydrophilic polymer

As used herein, “high molecular weight hydrophilic polymer” refers to a material having a weight average molecular weight of at least about 100,000 Daltons and increasing the wettability of the cured silicone hydrogel upon incorporation into the silicone hydrogel composition. The preferred weight average molecular weight of these high molecular weight hydrophilic polymers is at least about 150,000 Daltons, more preferably from about 150,000 to about 2,000,000 Daltons, particularly preferably from about 300,000 to about 1,800,000 Daltons, most preferably from about 500,000 to about 1,500,000 Daltons.

Alternatively, the molecular weight of the hydrophilic polymers of the present invention may be represented by K-values based on dynamic viscosity measurements (see Encyclopedia of Polymer Science and Engineering, N-Vinyl Amide Polymers, 2nd edition, Vol. 17, 198-). John Wiley & Sons Inc., p. 257). When represented in this manner, hydrophilic monomers having a K-value of at least about 46, preferably from about 46 to about 150, are preferred. High molecular weight hydrophilic polymers are present in the compositions of these devices in amounts sufficient to provide contact lenses that remain substantially free of surface deposits during use without surface modification. Typical periods of use are at least about 8 hours, preferably for several days of continuous wear, and more preferably for at least 24 hours without removal. Substantially free of surface deposits indicates that at least about 70%, preferably at least about 80%, more preferably at least about 90% of the lenses worn in the patient population show no deposits during the wear period when viewed with a slit lamp. Or just a little bit.

Suitable amounts of high molecular weight hydrophilic polymers are from about 1 to about 15 weight percent, more preferably from about 3 to about 15 weight percent, most preferably from about 5 to about 12 weight percent, based on the total amount of all reactive components.

Examples of high molecular weight hydrophilic polymers include, but are not limited to, polyamides, polylactones, polyimides, polylactams and hydroxylated polyamides, polylactones, polyimides, polylactams, for example hydroxyls such as lower molar amounts of HEMA After copolymerization with the functional monomer, the hydroxyl group of the resulting copolymer is reacted with a material containing radically polymerizable groups such as isocyanatoethyl methacrylate or methacryloyl chloride to functionalize the DMA. Included. Hydrophilic prepolymers prepared from DMA or n-vinyl pyrrolidone and glycidyl methacrylate may also be used. The glycidyl methacrylate ring can be opened to produce a diol, which, together with other hydrophilic prepolymers in the mixing system, is a high molecular weight hydrophilic polymer, a hydroxyl functionalized silicone containing monomer and any other that imparts miscibility. It can be used to increase the miscibility of groups. Preferred high molecular weight hydrophilic polymers are those containing cyclic moieties, preferably cyclic amides or cyclic imides in their backbones. High molecular weight hydrophilic polymers include, without limitation, poly-N-vinyl pyrrolidone, poly-N-vinyl-2-piperidone, poly-N-vinyl-2-caprolactam, poly-N-vinyl-3-methyl- 2-caprolactam, poly-N-vinyl-3-methyl-2-piperidone, poly-N-vinyl-4-methyl-2-piperidone, poly-N-vinyl-4-methyl-2-caprol Lactam, poly-N-vinyl-3-ethyl-2-pyrrolidone, and poly-N-vinyl-4,5-dimethyl-2-pyrrolidone, polyvinylimidazole, poly-N, N-dimethyl Acrylamide, polyvinyl alcohol, polyacrylic acid, polyethylene oxide, poly-2-ethyl oxazoline, heparin polysaccharide, polysaccharide, mixtures and copolymers thereof (block or random, branched, several chains, combs or Stars), with poly-N-vinylpyrrolidone (PVP) being particularly preferred. Copolymers such as graft copolymers of PVP can also be used.

High molecular weight hydrophilic polymers provide improved wettability, in particular improved in vivo wettability, for the medical device of the present invention. Without being bound by any theory, it is believed that the high molecular weight hydrophilic polymer is a hydrogen bond acceptor and that hydrogen is bound to water more effectively and hydrophilic in an aqueous environment. The absence of water promotes incorporation of the hydrophilic polymer into the reaction mixture. In addition to the specifically named high molecular weight hydrophilic polymers, when a high molecular weight polymer is added to the silicone hydrogel composition, the hydrophilic polymer does not (a) substantially phase separate from the reaction mixture and (b) impart wettability to the resulting cured polymer. Even high molecular weight polymers are expected to be useful in the present invention. In some embodiments, it is preferred that the high molecular weight hydrophilic polymer is soluble in the diluent at process temperatures. It may be preferable because the manufacturing method using water or water soluble diluent is simple and inexpensive. In these embodiments, high molecular weight hydrophilic polymers that are water soluble at the process temperature are preferred.

Hydroxyl-functionalized silicone-containing monomers

As used herein, a "hydroxyl functionalized silicone containing monomer" has an average molecular weight of less than about 5,000 Daltons, preferably less than about 3,000 Daltons, as measured by gel permeation chromatography, refractive index detection, Compounds containing at least one polymerizable group capable of admixing the included silicone containing monomers with the hydrophilic polymer. Hydroxyl functionality is very effective in improving the miscibility of hydrophiles. Thus, in a preferred embodiment, the hydroxyl functionalized silicone containing monomers of the invention comprise at least one hydroxyl group and at least one "-Si-O-Si-" group. The silicon and the oxygen bound thereto are preferably present at least about 10%, more preferably at least about 20%, by weight of the hydroxyl functionalized silicone containing monomer.

The ratio of Si to OH of the hydroxyl functionalized silicone containing monomers is also important for providing hydroxyl functionalized silicone containing monomers that provide the desired degree of miscibility. If the ratio of hydrophobic moiety to OH is too high, the hydroxyl functionalized silicone monomer may be incompatible with the hydrophilic polymer, resulting in an immiscible reaction mixture. Thus, in some embodiments the ratio of Si to OH is less than about 15: 1, preferably from about 1: 1 to about 10: 1. In some embodiments, the primary alcohol provides more improved miscibility than the secondary alcohol. Those skilled in the art will appreciate that the amount and type of hydroxyl functionalized silicone containing monomers depends on the amount of hydrophilic polymer required to achieve the desired wettability and the extent to which the silicone containing monomers are not miscible with the hydrophilic polymer.

In some embodiments, the reaction mixture of the present invention may comprise one or more hydroxyl functionalized silicone containing monomers. For monofunctional hydroxyl functionalized silicone containing monomers, preferred R ¹ is hydrogen, preferred R ² , R ³ and R ⁴ are C _1-6 alkyl and tri C _1-6 alkylsiloxy, most preferably methyl and Trimethylsiloxy. For polyfunctional (difunctional or higher), R ¹ to R ⁴ independently comprise ethylenically unsaturated polymerizable groups and more preferably acrylate, styryl, C _1-6 alkylacrylate, acrylamide, C _1-6 alkyl acrylamide, N- vinyl caprolactam, N- vinyl amide, C _2-12 alkenyl, C _2-12 alkenyl, phenyl, C _2-12 alkenyl, naphthyl, or C _2-6 alkenyl, phenyl C _1-6 alkyl. In some embodiments R ⁵ is hydroxyl, —CH ₂ OH or CH ₂ CHOHCH ₂ OH.

In some other embodiments, R ⁶ is divalent C _1-6 alkyl, C _1-6 alkyloxy, C _1-6 alkyloxyC _1-6 alkyl, phenylene, naphthalene, C _1-12 cycloalkyl, C _1-6 Alkoxycarbonyl, amide, carboxy, C _1-6 alkylcarbonyl, carbonyl, C _1-6 alkoxy, substituted C _1-6 alkyl, substituted C _1-6 alkyloxy, substituted C _1-6 alkyloxy C _1-6 alkyl, substituted phenylene, substituted naphthalene, substituted C _1-12 cycloalkyl, wherein the substituents are C _1-6 alkoxycarbonyl, C _1-6 alkyl, C _1-6 alkoxy, amide, Halogen, hydroxyl, carboxyl, C _1-6 alkylcarbonyl and formyl). Particularly preferred R ⁶ is divalent methyl (methylene).

In some embodiments, R ⁷ is acrylate, styryl, vinyl, vinyl ether, itaconate group, C _1-6 alkylacrylate, acrylamide, C _1-6 alkylacrylamide, N-vinyllactam, N-vinyl amide, C _2-12 alkenyl, C _2-12 alkenyl, phenyl, C _2-12 alkenyl, naphthyl, or C _2-6 free radical reactive group, such as alkenyl, phenyl-C _1-6 alkyl, or vinyl ether, or Cationic reactive groups such as epoxide groups. Especially preferred R ⁷ is methacrylate.

In some embodiments, R ⁸ is divalent C _1-6 alkyl, C _1-6 alkyloxy, C _1-6 alkyloxyC _1-6 alkyl, phenylene, naphthalene, C _1-12 cycloalkyl, C _1-6 alkoxy Carbonyl, amide, carboxy, C _1-6 alkylcarbonyl, carbonyl, C _1-6 alkoxy, substituted C _1-6 alkyl, substituted C _1-6 alkyloxy, substituted C _1-6 alkyloxyC _1-6 alkyl, substituted phenylene, substituted naphthalene, substituted C _1-12 cycloalkyl, wherein the substituents are C _1-6 alkoxycarbonyl, C _1-6 alkyl, C _1-6 alkoxy, amide, halogen , At least one member of the group consisting of hydroxyl, carboxyl, C _1-6 alkylcarbonyl and formyl). Particularly preferred R ⁸ is C _1-6 alkyloxyC _1-6 alkyl.

Examples of hydroxyl functionalized silicone containing monomers of Formula 1 include 2-propenic acid, 2-methyl-, 2-hydroxy-3- [3- [1,3,3,3-tetramethyl-1-[(trimethyl Silyl) oxy] disiloxanyl] propoxy] propyl ester (this is also referred to as (3-methacryloxy-2-hydroxypropyloxy) propylbis (trimethylsiloxy) methylsilane) (2). The compound, (3-methacryloxy-2-hydroxypropyloxy) propylbis (trimethylsiloxy) methylsilane, can be formed from an epoxide, which is formed from the compound and (2-methacryloxy-3-hydroxy To yield an 80:20 mixture of propyloxy) propylbis (trimethylsiloxy) methylsilane. In some embodiments of the present invention, it is preferred that the primary hydroxyl is present in some amount, preferably at least about 10% by weight, more preferably at least about 20% by weight.

Other suitable hydroxyl functionalized silicone containing monomers include (3-methacryloxy-2-hydroxypropyloxy) propyltris (trimethylsiloxy) silane (3), bis-3-methacryloxy-2-hydroxypropyl Oxypropyl polydimethylsiloxane (4), 3-methacryloxy-2- (2-hydroxyethoxy) propyloxy) propylbis (trimethylsiloxy) methylsilane (5), N, N, N ', N' -Tetrakis (3-methacryloxy-2-hydroxypropyl) -α, ω-bis-3-aminopropyl-polydimethylsiloxane.

Reaction products of glycidyl methacrylate with amino functional polydimethylsiloxanes may also be used as hydroxyl functionalized silicone containing monomers. Other additional constituents that may be suitable as hydroxyl functionalized silicone containing monomers include compounds having Formula 6, wherein n is from 1 to 50, and R independently comprises H or a polymerizable unsaturated group, but at least one R Includes polymerizable groups and includes one or more similar to R, preferably 3 to 8 R include H). These components can be removed from hydroxyl functionalized monomers by known methods such as liquid phase chromatography, distillation, recrystallization or extraction, or they can be prevented by careful selection of reaction conditions and reaction ratios.

Suitable monofunctional hydroxyl functionalized silicone monomers are commercially available from Gelest, Inc. (Morrisville, Pa). Suitable polyfunctional hydroxyl functionalized silicone monomers are commercially available from Gelest, Inc. (Morrisville, Pa), or may be prepared using known methods.

While hydroxyl functionalized silicone containing monomers have been found to be particularly suitable for providing miscible polymers for biomedical devices, particularly ophthalmic devices, they may be miscible with selected hydrophilic components when polymerized and / or molded into final products. Any functionalized silicone containing monomer can be used. Suitable functionalized silicone containing monomers can be selected using the following monomer miscibility tests. In this test, mono-3-methacryloxypropyl terminated, mono-butyl terminated polydimethylsiloxane (mPDMS MW 800 to 1,000) and 1 gram each of the monomers to be tested were subjected to 3,7-dimethyl-3- at about 20 ° C. Mix with 1 gram of octanol. A mixture of 12 parts by weight of K-90 PVP and 60 parts by weight of DMA is added dropwise to the hydrophobic component solution after stirring for 3 minutes until the solution becomes cloudy. The mass of the combination of PVP and DMA added is measured in grams and recorded as monomer miscibility. Hydroxyl functionalized silicone containing monomers having a degree of compatibility of at least 0.2 grams, more preferably at least about 0.7 grams, and most preferably at least about 1.5 grams, will be suitable for use in the present invention.

An "effective amount" or "miscible effective amount" of a hydroxyl functionalized silicone containing monomer of the present invention is the amount necessary to blend or dissolve the high molecular weight hydrophilic polymer and other components of the polymerization composition. Thus, the amount of hydroxyl functionalized silicone containing monomer will depend in part on the amount of hydrophilic polymer used, with higher concentrations of hydrophilic polymer will result in higher amount of hydroxyl functionalized silicone containing monomer required to blend it. The effective amount of hydroxyl functionalized silicone containing monomer in the polymer composition is from about 5% (weight percentage based on the weight of the reactive components) to about 90%, preferably about 10% to about 80%, most preferably about 20 % To about 50%.

In addition to the high molecular weight hydrophilic polymers and hydroxyl functionalized silicone containing monomers of the invention, other hydrophilic and hydrophobic monomers, crosslinkers, additives, diluents, polymerization initiators can also be used to make the biomedical devices of the invention. In addition to high molecular weight hydrophilic polymers and hydroxyl functionalized silicone containing monomers, the hydrogel composition may comprise additional silicone containing monomers, hydrophilic monomers and crosslinkers to provide the biomedical devices of the present invention.

Additional silicone-containing monomers

For further silicone-containing monomers, 3-methacryloxypropyltris (trimethylsiloxy) silane (TRIS), monomethacryloxypropyl terminated polydimethylsiloxane, polydimethylsiloxane, 3-methacryloxypropylbis (trimethylsiloxane Useful amide homologues of TRIS, which may include c) methylsilane, methacryloxypropylpentamethyl disiloxane and combinations thereof, are particularly useful as further silicone containing monomers of the present invention. The additional silicone containing monomer may be present in an amount of about 0 to about 75 weight percent, more preferably about 5 to about 60 weight percent, most preferably about 10 to 40 weight percent.

Hydrophilic monomers

Additional reactive components of the present invention may also include any hydrophilic monomers used in the manufacture of conventional hydrogels. For example, monomers containing an acrylic group (CH ₂ .dbd.CRCOX, where R is hydrogen or C _1-6 alkyl and X is O or N) or vinyl group (-C.dbd.CH ₂ ) are used. It is possible. Examples of further hydrophilic monomers include N, N-dimethylacrylamide, 2-hydroxyethyl methacrylate, glycerol monomethacrylate, 2-hydroxyethyl methacrylamide, polyethyleneglycol monomethacrylate, methacrylic acid, Acrylic acid, N-vinyl pyrrolidone, N-vinyl-N-methyl acetamide, N-vinyl-N-ethyl acetamide, N-vinyl-N-ethyl formamide, N-vinyl formamide and combinations thereof .

In addition to the additional hydrophilic monomers mentioned above, polyoxyethylene polyols having at least one terminal hydroxyl group substituted with a functional group containing a polymerizable double bond can also be used. Examples include end-blocking groups such as polyethylene glycol, ethoxylated alkyl glucosides and ethoxylated bisphenol A with at least one molar equivalent of isocyanatoethyl methacrylate, methacrylic anhydride, methacryloyl chloride, vinylbenzoyl chloride, and the like. Polyethylene polyols having at least one terminal polymerizable olefin group bonded via a linking moiety, such as a carbamate, urea or ester group, produced by reacting together.

Still other examples include hydrophilic vinyl carbonate or vinyl carbamate monomers, hydrophilic oxazolone monomers and polydextran.

Further hydrophilic monomers are N, N-dimethylacrylamide (DMA), 2-hydroxyethyl methacrylate (HEMA), glycerol methacrylate, 2-hydroxyethyl methacrylamide, N-vinylpyrrolidone (NVP ), Polyethylene glycol monomethacrylate, methacrylic acid, acrylic acid and combinations thereof. The additional hydrophilic monomer may be present in an amount of about 0 to about 70% by weight, more preferably about 5 to about 60% by weight, most preferably about 10 to 50% by weight.

Crosslinker

Suitable crosslinkers are compounds having two or more polymerizable functional groups. Crosslinkers can be hydrophilic or hydrophobic, and in some embodiments of the invention it has been found that a mixture of hydrophilic and hydrophobic crosslinkers provides silicone hydrogels with improved optical clarity (reduced haze compared to CSI thin lenses). Examples of suitable hydrophilic crosslinkers include compounds having two or more polymerizable functional groups and hydrophilic functional groups such as polyether, amide or hydroxyl groups. Specific examples include TEGDMA (tetraethyleneglycol dimethacrylate), TrEGDMA (triethyleneglycol dimethacrylate), ethyleneglycol dimethacrylate (EGDMA), ethylenediamine dimethacrylamide, glycerol dimethacrylate and their Formulations are included. Examples of suitable hydrophobic crosslinkers include polyfunctional hydroxyl functionalized silicone containing monomers, polyfunctional polyether-polydimethylsiloxane block copolymers, combinations thereof, and the like. Specific hydrophobic crosslinkers include acryloxypropyl terminated polydimethylsiloxanes (n = 10 or 20) (acPDMS), hydroxylacrylate functionalized siloxane macromonomers, methacryloxypropyl terminated PDMS, butanediol dimethacrylate, di Vinyl benzene, 1,3-bis (3-methacryloxypropyl) -tetrakis (trimethylsiloxy) disiloxane and mixtures thereof. Preferred crosslinkers include TEGDMA, EGDMA, acPDMS and combinations thereof. The amount of the hydrophilic crosslinking agent is generally about 0 to about 2% by weight, preferably about 0.5 to about 2% by weight, and the amount of hydrophobic crosslinker is about 0 to about 5% by weight, which is alternatively about 0.01 to about 0.01% by weight. About 0.2 mmol / g (reactive component), preferably about 0.02 to about 0.1, more preferably 0.03 to about 0.6 mmol / g.

Increasing the concentration of crosslinker in the final polymer was found to decrease the degree of haze. However, when the concentration of the crosslinker is increased to about 0.15 mmol / g or more, the reactive component coefficient may generally increase beyond the desired level (about 90 psi or more). Thus, in some embodiments of the present invention the composition and amount of the crosslinker is selected such that the crosslinker concentration in the reaction mixture is from about 0.01 to about 0.1 mmol / g.

Additional components or additives generally known in the art may also be used. Additives include, without limitation, ultraviolet absorbing compounds and monomers, reactive colorants, antimicrobial compounds, pigments, photochromic materials, release agents, combinations thereof, and the like.

Additional components include other oxygen permeable components such as carbon-carbon triple bond-containing monomers and fluorine-containing monomers known in the art, and include fluorine-containing (meth) acrylates, more specifically, for example, 2, 2,2-trifluoroethyl (meth) acrylate, 2,2,2,2 ', 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, 2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9-hexadecafluorononyl (meth) acrylate and the like ( Fluorine-containing C ₂ -C ₁₂ alkyl esters of meth) acrylic acid.

diluent

Reactive components (hydroxyl functionalized silicone containing monomers, hydrophilic polymers, crosslinker (s) and other components) are generally mixed and reacted in the absence of water, optionally in the presence of one or more diluents, to form a reaction mixture. The type and amount of diluents used also influences the properties of the polymers and products obtained. Haze and wettability of the final product can be improved by selecting relatively hydrophobic diluents and / or reducing the concentration of diluents used. As discussed above, increasing the hydrophobicity of the diluent also allows processing of poorly miscible components (as measured by miscibility tests) to form products with miscible polymers. However, as the diluent becomes more hydrophobic, it will be necessary to use solvents other than water in the process steps necessary to replace the diluent with water. This may undesirably complicate the manufacturing process and increase costs. Therefore, it is important to select a diluent that gives the components the desired miscibility while providing the required level of ease of processing. Diluents useful in preparing the devices of the present invention include ethers, esters, alkanes, alkyl halides, silanes, amides, alcohols and combinations thereof. Amides and alcohols are the preferred diluents, and secondary and tertiary alcohols are the most preferred diluents. Examples of ethers useful as diluents in the present invention include tetrahydrofuran, tripropylene glycol methyl ether, dipropylene glycol methyl ether, ethylene glycol n-butyl ether, diethylene glycol n-butyl ether, diethylene glycol methyl ether, ethylene glycol phenyl Ether, propylene glycol methyl ether, propylene glycol methyl ether acetate, dipropylene glycol methyl ether acetate, propylene glycol n-propyl ether, dipropylene glycol n-propyl ether, tripropylene glycol n-butyl ether, propylene glycol n-butyl ether, Dipropylene glycol n-butyl ether, tripropylene glycol n-butyl ether, propylene glycol phenyl ether, dipropylene glycol dimethyl ether, polyethylene glycol, polypropylene glycol and mixtures thereof. Examples of esters useful in the present invention include ethyl acetate, butyl acetate, amyl acetate, methyl lactate, ethyl lactate, i-propyl lactate. Examples of alkyl halides useful as diluents in the present invention include methylene chloride. Examples of silanes useful as diluents in the present invention include octamethylcyclotetrasiloxane.

Examples of alcohols useful as diluents in the present invention include compounds of formula 7, wherein R, R 'and R "are H, or halogen, ether, ester, aryl, amine, amide, alkene, alkyne, carboxylic acid, alcohol, aldehyde, Independently selected from linear, branched, or cyclic monovalent alkyl having 1 to 10 carbon atoms which may be optionally substituted with one or more groups including ketones, or the like, or any two or three of R, R and R "may be bonded together To form one or more cyclic structures, such as alkyl having 1 to 10 carbon atoms, which may be substituted as described above, provided that only one of R, R 'or R "is H.

R, R 'and R "are preferably selected independently from H or an unsubstituted linear, branched or cyclic alkyl group having 1 to 7 carbon atoms. R, R' and R" are substituted with 1 to 7 carbon atoms. More preferably, they are independently selected from unsubstituted linear, branched or cyclic alkyl groups. In certain embodiments, preferred diluents have a total of 4 or more, more preferably 5 or more, because higher molecular weight diluents have lower volatility and lower flammability. If one of R, R 'and R "is H, the formula forms a secondary alcohol. If none of R, R' and R" is H, the formula forms a tertiary alcohol. Tertiary alcohols are more preferred than secondary alcohols. The diluent is preferably inert and can be easily substituted by water when the total carbon number is 5 or less. Examples of useful secondary alcohols include 2-butanol, 2-propanol, menthol, cyclohexanol, cyclopentanol and exonorbornol, 2-pentanol, 3-pentanol, 2-hexanol, 3-hexanol, 3-methyl-2-butanol, 2-heptanol, 2-octanol, 2-nonanol, 2-decanol, 3-octanol, norborneneol and the like.

Examples of useful tertiary alcohols include tert-butanol, tert-amyl, alcohols, 2-methyl-2-pentanol, 2,3-dimethyl-2-butanol, 3-methyl-3-pentanol, 1-methyl Cyclohexanol, 2-methyl-2-hexanol, 3,7-dimethyl-3-octanol, 1-chloro-2-methyl-2-propanol, 2-methyl-2-heptanol, 2-methyl-2 -Octanol, 2,2-methyl-2-nonanol, 2-methyl-2-decanol, 3-methyl-3-hexanol, 3-methyl-3-heptanol, 4-methyl-4-heptanol , 3-methyl-3-octanol, 4-methyl-4-octanol, 3-methyl-3-nonanol, 4-methyl-4-nonanol, 3-methyl-3-octanol, 3-ethyl- 3-hexanol, 3-methyl-3-heptanol, 4-ethyl-4-heptanol, 4-propyl-4-heptanol, 4-isopropyl-4-heptanol, 2,4-dimethyl-2- Pentanol, 1-methylcyclopentanol, 1-ethylcyclopentanol, 1-ethylcyclopentanol, 3-hydroxy-3-methyl-1-butene, 4-hydroxy-4-methyl-1-cyclopentane Ol, 2-phenyl-2-propanol, 2-methoxy-2-methyl-2-propanol, 2,3,4-trimethyl-3-pentanol, 3,7-dimethyl-3-octanol, 2-phenyl Part II Ol, and the like of 2-methyl-1-phenyl-2-propanol and 3-ethyl-3-pentanol.

The polymer of the present invention may be prepared using a single alcohol, or two or more alcohols described above or a mixture of two or more alcohols according to the above formula as a diluent.

In certain embodiments, preferred alcohol diluents are secondary and tertiary alcohols having four or more carbons. In particular, some alcohol diluents include tert-butanol, tert-amyl alcohol, 2-butanol, 2-methyl-2-pentanol, 2,3-dimethyl-2-butanol, 3-methyl-3-pentanol, 3-ethyl-3-pentanol, 3,7-dimethyl-3-octanol.

Diluents are hexanol, heptanol, octanol, nonanol, decanol, tert-butyl alcohol, 3-methyl-3-pentanol, isopropanol, tert-amyl alcohol, ethyl lactate, methyl lactate, i- Propyl lactate, 3,7-dimethyl-3-octanol, dimethyl formamide, dimethyl acetamide, dimethyl propionamide, N-methyl pyrrolidinone and mixtures thereof.

In some embodiments of the invention, the diluent is water soluble at process conditions and can be easily washed out of the lens in a short time using water. Suitable water-soluble diluents include 1-ethoxy-2-propanol, 1-methyl-2-propanol, tert-amyl alcohol, tripropylene glycol methyl ether, isopropanol, 1-methyl-2-pyrrolidone, N, N- Dimethylpropionamide, ethyl lactate, dipropylene glycol methyl ether, mixtures thereof, and the like. The use of a water soluble diluent allows the subsequent molding process to be carried out using only water or an aqueous solution containing water as a substantial component.

In some embodiments, the amount of diluent may generally be less than about 50%, preferably less than about 40%, more preferably about 10 to about 30% of the reaction mixture. In some embodiments, the diluent may include additional ingredients such as a release agent and a water soluble lens deblocking aid.

Polymerization initiators include, for example, compounds such as lauryl peroxide, benzoyl peroxide, isopropyl percarbonate, azobisisobutyronitrile and the like, which generate free radicals at moderately elevated temperatures, and aromatic alpha-hydroxy ketones, Photoinitiator systems such as alkoxyoxybenzoin, acetophenone, acyl phosphine oxide and tertiary amines with diketones, mixtures thereof, and the like. Representative examples of photoinitiators include 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, bis (2,6-dimethoxybenzoyl) -2,4,4- Trimethylpentyl phosphine oxide (DMBAPO), bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide (irgacure 819), 2,4,6-trimethylbenzyldiphenyl phosphine oxide and 2,4, 6-trimethylbenzoyl diphenylphosphine oxide, benzoin methyl ester, and a combination of camphorquinone and ethyl 4- (N, N-dimethylamino) benzoate. Commercially available visible light photoinitiator systems include Irgacure 819, Irgacure 1700, Irgacure 1800, Irgacure 819, Irgacure 1850 (Ciba Specialty Chemicals) and Lucirin TPO Initiator (BASF). Included. Commercially available UV photoinitiators include Darocure 1173 and Darocure 2959 (Ciba Specialty Chemicals). The initiator is used in the reaction mixture in an amount effective to initiate photopolymerization of the reaction mixture, for example from about 0.1 to about 2 parts by weight per 100 parts by weight of the reactive monomer. Polymerization of the reaction mixture may be initiated by the appropriate choice of heat, visible or ultraviolet light or other means depending on the polymerization initiator used. Alternatively, initiation may be performed without photoinitiators, for example using e-beams. However, when using a photoinitiator, in some embodiments a combination of 1-hydroxycyclohexyl phenyl ketone and bis (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentyl phosphine oxide (DMBAPO) can be used. And the polymerization initiation method may include visible light. Another aspect may include bis (2,4,6-trimethylbenzoyl) -phenylphosphineoxide (Irgacure 819.RTM).

In some embodiments, the present invention may further comprise an ophthalmic lens of the composition: 1 wt% component HFSCM HMWHP SCM HM 5-90 1-15, 3-15 or 5-12 0 0 10-80 1-15, 3-15 or 5-12 0 0 20-50 1-15, 3-15 or 5-12 0 0 5-90 1-15, 3-15 or 5-12 0-80, 5-60 Or 10- 0-70, 5-60 or 10-40 50 10-80 1-15, 3-15 or 5-12 0-80, 5-60 or 10- 0-70, 5-60 or 10-40 50 20-50 1-15, 3-15 or 5-12 0-80, 5-60 or 10- 0-70, 5-60 or 10-40 50. HFSCM is a hydroxyl functionalized silicone containing monomer, HMWHP Is a high molecular weight hydrophilic polymer, SCM is a silicone containing monomer and HM is a hydrophilic monomer.

The weight percentage can be based on all reactive components. Thus, in some embodiments the invention may comprise one or more of silicone hydrogels, biomedical devices, ophthalmic devices and contact lenses, wherein one or more of the compositions are each listed in a table describing 90 possible composition ranges. . Each range contemplated is prefixed with "about" to provide a range combination, provided that the listed ingredients and any additional ingredients are added up to 100% by weight.

The blending range of the silicone containing monomers (hydroxyl functionalized silicone containing and additional silicone containing monomers) is from about 5 to 99% by weight of the reactive components, more preferably from about 15 to 90% by weight, in some embodiments from about 25 to about 80 Weight percent. The range of hydroxyl functionalized silicone containing monomers is from about 5 to about 90 weight percent, preferably from about 10 to about 80 weight percent, most preferably from about 20 to about 50 weight percent. In some embodiments, the range of hydrophilic monomers is from about 0% to about 70%, more preferably from about 5% to about 60%, most preferably from about 10% to about 50% by weight of the reactive components. In some embodiments the range of high molecular weight hydrophilic polymer may be about 1 to about 15 weight percent, or about 3 to about 15 weight percent, or about 5 to about 12 weight percent. All weight percentages are based on the total amount of all reactive components.

In some embodiments, the diluent ranges from about 0 to about 70 weight percent, or from about 0 to about 50 weight percent, or from about 0 to about 40 weight percent, in some embodiments from about 10 to about 40 weight percent, based on the weight of all components in the reaction mixture. About 30% by weight. The amount of diluent required depends on the nature and relative amounts of the reactive components.

In some embodiments, the reactive components are 2-propenic acid, 2-methyl-, 2-hydroxy-3- [3- [1,3,3,3-tetramethyl-1-[(trimethylsilyl) oxy] disiloxane Sanyl] propoxy] propyl ester "SiGMA" (about 28% by weight of reactive components), 800-1000 MW monomethacryloxypropyl terminated mono-n-butyl terminated polydimethylsiloxane "mPDMS" (about 31% by weight) ), N, N-dimethylacrylamide "DMA" (about 24% by weight), 2-hydroxyethyl methacrylate "HEMA" (about 6% by weight), tetraethylene glycol dimethacrylate "TEGDMA" (about 1.5 Weight percent), and polyvinylpyrrolidone "K-90 PVP" (about 7 weight percent) with small amounts of additives and photoinitiators. The polymerization may be carried out in the presence of about 23% (% by weight of the combined monomer and diluent combination) of 3,7-dimethyl-3-octanol diluent.

In some embodiments, the polymerization for the composition may be carried out in the presence of about 29% by weight of tert-amyl-alcohol of the uncured reaction mixture as diluent.

Processing

In some embodiments, the ophthalmic lens of the present invention mixes a high molecular weight hydrophilic polymer, a hydroxyl functionalized silicone containing monomer, and one or more additional silicone containing monomers, hydrophilic monomers, additives (“reactive components”) and diluents with a polymerization initiator. And (collectively referred to as "reaction mixture"), the reaction mixture can be prepared by curing under suitable conditions to form a product, which is then shaped into a predetermined shape by turning, cutting or the like. Alternatively, the reaction mixture may be added to a mold and then cured into a suitable product.

Various methods are known for processing the reaction mixture in the manufacture of contact lenses, including centrifugal casting and stationary casting. In some embodiments, contact lenses of the polymers of the invention are made by molding silicone hydrogels. During molding, the reaction mixture is introduced into a final desired silicone hydrogel, i.e., a mold having the shape of a water-expanded polymer, and the reaction mixture is treated under monomer polymerization conditions to bring the polymer / diluent mixture into the shape of the final desired product. Create The polymer / diluent mixture is then treated with a solution to remove the diluent and finally replaced by water, thereby providing a silicone hydrogel with a final size and shape very similar to the size and shape of the initially molded polymer / diluent product. Create

Hardening

Another aspect of some embodiments of the present invention includes a process of curing the silicone hydrogel composition in a manner that provides improved wettability. In accordance with the present invention, it has been found that the gelation time for silicone hydrogels may be correlated with the curing conditions for providing wettable ophthalmic devices, in particular contact lenses. The gelation time here is the time when the crosslinked network polymer is formed such that the viscosity of the curing reaction mixture approaches infinity and the reaction mixture does not flow. The gel point can be used as an indicator of the reaction rate because it occurs at a specific degree of conversion regardless of the reaction conditions. It has been found that the gelation time can be used to determine the curing conditions that impart the desired wettability for a given reaction mixture. Thus, in some embodiments of the present invention the reaction mixture may be cured above gelling time (“minimum gelation time”), which provides improved wettability and, in some embodiments, sufficient wettability to produce a device used without hydrophilic coating or surface treatment. Can be. In some embodiments, improved wettability can reduce the forward contact angle by at least 10% compared to compositions that do not contain high molecular weight polymers. Thus, in some embodiments, longer gelling times are desirable because they provide improved wettability and increased processing flexibility.

Gelation times may vary for different silicone hydrogel compositions. Curing conditions can also affect gelation time. For example, in some embodiments the concentration of the crosslinker affects the gelation time, with increasing concentration of the crosslinker shortening the gelation time. Gelation also increases radiation intensity (for photopolymerization) or temperature (for thermal polymerization), increases in initiation efficiency (increases by selecting a more effective initiator or radiation source, or by selecting an initiator that absorbs more strongly in the selected radiation range) It will save you time. The temperature and type and concentration of diluent can also affect the gelation time as those skilled in the art will understand.

In some embodiments, the minimum gelation time can be determined by selecting a given composition, changing one of the factors and measuring the gelation time and contact angle. Thus the minimum gelation time can be the point in time when the resulting lens is generally wettable. Below the minimum gelation time the lens cannot wet. In the present description of contact lenses, lenses that are “wet generally” exhibit a forward dynamic contact angle of less than about 80 degrees, in some cases less than 70 degrees, and in another embodiment less than about 60 degrees. As such, those skilled in the art will appreciate that the minimum gel point defined herein may be in the range given statistical experimental variability.

In certain embodiments a minimum gelation time of at least about 30 seconds using visible light emission has been found to be advantageous.

In some embodiments the template containing the reaction mixture is exposed to ionic or actinic radiation, such as electron beams, X-rays, UV or visible light, ie electromagnetic radiation or particle radiation having a wavelength in the range of about 150 to about 800 nm. In some embodiments, the radiation source is UV or visible light having a wavelength of about 250 to about 700 nm. Suitable radiation sources include UV lamps, fluorescent lamps, incandescent lamps, mercury vapor lamps, and sunlight. In embodiments in which the UV absorbing compound is included in the composition (eg as a UV blocker), curing may be performed by means other than UV irradiation (eg visible light or heat). In some preferred embodiments, the radiation source can be selected at low intensity from UVA (about 315 to about 400 nm), UVB (about 280 to about 315 nm) or visible light (about 400 to about 450 nm).

In another embodiment, the reaction mixture comprises a UV absorbing compound and is cured using visible light at low intensity. "Low intensity" means here an intensity of about 0.1 mW / cm 2 to about 6 mW / cm 2, preferably about 0.2 mW / cm 2 to about 3 mW / cm 2. The curing time is therefore relatively long and can generally be about 1 minute or more, preferably about 1 to about 60 minutes, more preferably about 1 to about 30 minutes. In some embodiments, relatively slow low intensity cure can provide compatible ophthalmic devices that exhibit sustained resistance to protein deposition in vivo.

In some embodiments, the temperature at which the reaction mixture cures can increase above ambient temperature, where the haze of the resulting polymer is reduced. Temperatures effective to reduce haze include temperatures at which the haze for the resulting lens is reduced by at least about 20% relative to the lenses of the same composition made at 25 ° C. Thus, in some embodiments suitable curing temperatures may include temperatures higher than about 25 ° C. In certain embodiments a range of about 25 ° C. to 70 ° C. and about 40 ° C. to 70 ° C. may be included. The exact setting of the curing conditions (temperature, intensity and time) may vary depending upon the components of the lens material selected and are determined within the skill of one of ordinary skill in the art with reference to the teachings herein. Curing may be carried out in one or several curing zones and should preferably be sufficient to form a network polymer from the reaction mixture. Typically, the resulting network polymer may be expanded by a diluent and take the form of a mold cavity.

Although the present invention has been described from one or more methodological aspects, the present invention relates to mold handling equipment, hydration towers, impregnation tanks, automatic control systems, monomer dispersers, curing that can be used to perform one or more of the steps described herein. Devices and systems such as tunnels, heat exchangers and the like are also included without limitation.

Lenses are made according to the above description and with 24 parts of N, N-dimethylacrylamide and 0.48 ppm CGI 1850 using concave mold parts combined with convex molds. After photocuring, the mold part is removed and the lens in the concave mold part is placed in the stirred aqueous solution shown in Table 1. Each aqueous solution contained a surfactant as indicated in the column titled Reagent in Table 1. The time until the lens is released from the mold and completely detached is measured and further shown in Table 1.

As shown in Table 1, exposure to the aqueous solution containing the surfactant further had a D30 leaching effect from the lens.

The lenses were stirred in each aqueous solution for a total time as described in Table 1, then taken out and extracted with isopropanol to remove residual D3O diluent. Isopropanol extracts are analyzed for D3O and the results are listed in Table 1 as a percentage of the levels found in the unleached control lens.

exam reagent Temperature Ml / lens Residual D3O Release time (minutes) Leaching time (min) One 20% Texapon 845 90 ℃ 35 0.24% 25 25 2 20% 1,2-hexanediol 90 ℃ 35 0.40% 20 20 3 20% Sulfotex OA 90 ℃ 35 0.61% 35 35 contrast 90 ℃ 35 100% No variant 100%

Claims (60)

Exposing an ophthalmic lens comprising silicon to a first aqueous solution comprising at least about 20% of a first release agent comprising Texapon 845; and Heating the first aqueous solution exposing the ophthalmic lens A method for releasing an ophthalmic lens comprising a silicone from a mold part comprising a. The method of claim 1, Removing unreacted components and diluents from the ophthalmic lens by exposing the ophthalmic lens to the first aqueous solution, and Washing the ophthalmic lens by contacting a second aqueous solution until the ophthalmic lens contains unreacted components and diluents at levels below a predetermined threshold. How to further include. The method of claim 2, wherein the lens is exposed to the first aqueous solution for at least about 20 minutes. The method of claim 2, wherein the first liquid, the second liquid, or both comprise a buffered aqueous solution. The method of claim 4, wherein the first liquid, the second liquid, or both, sodium chloride, boric acid, sodium borate, dihydrogen sodium phosphate, sodium citrate, sodium acetate, sodium bicarbonate or combinations thereof How to include. The method of claim 2, wherein the predetermined threshold comprises a threshold for detection of unreacted components and diluents. The method of claim 2, wherein the ophthalmic lens comprises a contact lens comprising 0 to about 90% water. The method of claim 2, wherein the ophthalmic lens further comprises a diluent, and further comprising removing the diluent from the ophthalmic lens. The method of claim 8, wherein the ophthalmic lens has a functional size and is expanded during the removal of the diluent. The method of claim 2, wherein the ophthalmic lens is a colored lens. The method of claim 2, wherein the ophthalmic lens comprises a pattern of colorants. The method of claim 2 wherein the ophthalmic lens is formed from a reaction mixture comprising a high molecular weight hydrophilic polymer and an effective amount of a hydroxyl functionalized silicone containing monomer. The biomedical device of claim 2 wherein the effective amount of the hydroxyl functionalized silicone containing monomer is from about 5% to about 90%. The method of claim 1, wherein the ophthalmic lens is formed from a reaction mixture comprising from about 1% to about 15% high molecular weight hydrophilic polymer. The method of claim 1, wherein the poly-N-vinyl pyrrolidone, poly-N-vinyl-2-piperidone, poly-N-vinyl-2-caprolactam, poly-N-vinyl-3-methyl-2- Caprolactam, poly-N-vinyl-3-methyl-2-piperidone, poly-N-vinyl-4-methyl-2-piperidone, poly-N-vinyl-4-methyl-2-caprolactam, Poly-N-vinyl-3-ethyl-2-pyrrolidone, and poly-N-vinyl-4,5-dimethyl-2-pyrrolidone, polyvinylimidazole, poly-N, N-dimethylacrylamide To cure a monomer comprising a group consisting of polyvinyl alcohol, polyacrylic acid, polyethylene oxide, poly-2-ethyl oxazoline, heparin polysaccharide, polysaccharide, mixtures and copolymers thereof to form an ophthalmic lens. The method further comprises a step. The method of claim 2, wherein washing the ophthalmic lens comprises exposing the ophthalmic lens three times to at least 35 ml of deionized water. The method of claim 2, wherein N, N-dimethylacrylamide, 2-hydroxyethyl methacrylate, glycerol methacrylate, 2-hydroxyethyl methacrylamide, polyethylene glycol monomethacrylate, methacrylic acid, acrylic acid, N-vinyl pyrrolidone, N-vinyl-N-methyl acetamide, N-vinyl-N-ethyl acetamide, N-vinyl-N-ethyl formamide, N-vinyl formamide, hydrophilic vinyl carbonate monomer, vinyl carba And curing the monomer comprising a group consisting of a mate monomer, a hydrophilic oxazolone monomer and a polydextran to form an ophthalmic lens. The method of claim 2, wherein the first aqueous solution is heated to about 90 ° C. or higher. The method of claim 2, wherein exposing the ophthalmic lens to the first aqueous solution comprises impregnating the lens with the first aqueous solution. The method of claim 2, wherein exposing the ophthalmic lens to the first aqueous solution comprises flowing the first aqueous solution over the lens. Exposing an ophthalmic lens comprising silicon to a first aqueous solution comprising at least about 20% of a first release agent comprising 1,2-hexanediol; and Heating the first aqueous solution exposing the ophthalmic lens A method for releasing an ophthalmic lens comprising a silicone from a mold part comprising a. The method of claim 21, Removing unreacted components and diluents from the ophthalmic lens by exposing the ophthalmic lens to the first aqueous solution, and Washing the ophthalmic lens by contacting a second aqueous solution until the ophthalmic lens contains unreacted components and diluents at levels below a predetermined threshold. How to further include. The method of claim 22, wherein the lens is exposed to the first aqueous solution for at least about 20 minutes. The method of claim 22, wherein the first liquid, the second liquid, or both comprise a buffered aqueous solution. The method of claim 24, wherein the first liquid, the second liquid, or both are selected from sodium chloride, boric acid, sodium borate, dihydrogen sodium phosphate, sodium citrate, sodium acetate, sodium bicarbonate, or combinations thereof. How to include. The method of claim 22, wherein the predetermined threshold comprises a threshold for detection of unreacted components and diluents. The method of claim 22, wherein the ophthalmic lens comprises a contact lens comprising 0 to about 90% water. 23. The method of claim 22, wherein the ophthalmic lens further comprises a diluent, and further comprising removing the diluent from the ophthalmic lens. The method of claim 28, wherein the ophthalmic lens has a functional size and is expanded during the removal of the diluent. The method of claim 22, wherein the ophthalmic lens is a colored lens. The method of claim 22, wherein the ophthalmic lens comprises a pattern of colorant. The method of claim 22, wherein the ophthalmic lens is formed from a reaction mixture comprising a high molecular weight hydrophilic polymer and an effective amount of hydroxyl functionalized silicone containing monomer. The biomedical device of claim 22 wherein the effective amount of the hydroxyl functionalized silicone containing monomer is from about 5% to about 90%. The method of claim 22, wherein the ophthalmic lens is formed from a reaction mixture comprising from about 1% to about 15% high molecular weight hydrophilic polymer. The method of claim 22, wherein the poly-N-vinyl pyrrolidone, poly-N-vinyl-2-piperidone, poly-N-vinyl-2-caprolactam, poly-N-vinyl-3-methyl-2- Caprolactam, poly-N-vinyl-3-methyl-2-piperidone, poly-N-vinyl-4-methyl-2-piperidone, poly-N-vinyl-4-methyl-2-caprolactam, Poly-N-vinyl-3-ethyl-2-pyrrolidone, and poly-N-vinyl-4,5-dimethyl-2-pyrrolidone, polyvinylimidazole, poly-N, N-dimethylacrylamide To cure a monomer comprising a group consisting of polyvinyl alcohol, polyacrylic acid, polyethylene oxide, poly-2-ethyl oxazoline, heparin polysaccharide, polysaccharide, mixtures and copolymers thereof to form an ophthalmic lens. The method further comprises a step. The method of claim 22, wherein washing the ophthalmic lens comprises exposing the ophthalmic lens three times to at least 35 ml of deionized water. 23. The composition of claim 22 wherein N, N-dimethylacrylamide, 2-hydroxyethyl methacrylate, glycerol methacrylate, 2-hydroxyethyl methacrylamide, polyethyleneglycol monomethacrylate, methacrylic acid, acrylic acid , N-vinyl pyrrolidone, N-vinyl-N-methyl acetamide, N-vinyl-N-ethyl acetamide, N-vinyl-N-ethyl formamide, N-vinyl formamide, hydrophilic vinyl carbonate monomer, vinyl And curing the monomer comprising a group consisting of a carbamate monomer, a hydrophilic oxazolone monomer and a polydextran to form an ophthalmic lens. The method of claim 22, wherein the first aqueous solution is heated to about 90 ° C. or higher. The method of claim 22, wherein exposing the ophthalmic lens to the first aqueous solution comprises impregnating the lens with the first aqueous solution. 23. The method of claim 22, wherein exposing the ophthalmic lens to a first aqueous solution comprises flowing the first aqueous solution over the lens. Exposing an ophthalmic lens comprising silicon to a first aqueous solution comprising at least about 20% of a first release agent comprising Sulfotex OA, and Heating the first aqueous solution exposing the ophthalmic lens A method for releasing an ophthalmic lens comprising a silicone from a mold part comprising a. The method of claim 41, wherein Removing unreacted components and diluents from the ophthalmic lens by exposing the ophthalmic lens to the first aqueous solution, and Washing the ophthalmic lens by contacting a second aqueous solution until the ophthalmic lens contains unreacted components and diluents at levels below a predetermined threshold. How to further include. The method of claim 42, wherein the lens is exposed to the first aqueous solution for at least about 20 minutes. 43. The method of claim 42, wherein said first liquid, said second liquid, or both, comprise a buffered aqueous solution. 45. The method of claim 44, wherein the first liquid, the second liquid, or both are sodium chloride, boric acid, sodium borate, dihydrogen sodium phosphate, sodium citrate, sodium acetate, sodium bicarbonate, or combinations thereof. How to include. 43. The method of claim 42, wherein the predetermined threshold comprises a threshold for detection of unreacted components and diluents. 43. The method of claim 42, wherein the ophthalmic lens comprises a contact lens comprising 0 to about 90% water. 43. The method of claim 42, wherein the ophthalmic lens further comprises a diluent, and further comprising removing the diluent from the ophthalmic lens. 49. The method of claim 48, wherein the ophthalmic lens has a functional size and is expanded during the removal of the diluent. 43. The method of claim 42, wherein the ophthalmic lens is a colored lens. 43. The method of claim 42, wherein the ophthalmic lens comprises a pattern of colorants. 43. The method of claim 42, wherein the ophthalmic lens is formed from a reaction mixture comprising a high molecular weight hydrophilic polymer and an effective amount of hydroxyl functionalized silicone containing monomer. 43. The biomedical device of claim 42, wherein the effective amount of the hydroxyl functionalized silicone containing monomer is from about 5% to about 90%. 43. The method of claim 42, wherein the ophthalmic lens is formed from a reaction mixture comprising from about 1% to about 15% high molecular weight hydrophilic polymer. The method of claim 42, wherein the poly-N-vinyl pyrrolidone, poly-N-vinyl-2-piperidone, poly-N-vinyl-2-caprolactam, poly-N-vinyl-3-methyl-2- Caprolactam, poly-N-vinyl-3-methyl-2-piperidone, poly-N-vinyl-4-methyl-2-piperidone, poly-N-vinyl-4-methyl-2-caprolactam, Poly-N-vinyl-3-ethyl-2-pyrrolidone, and poly-N-vinyl-4,5-dimethyl-2-pyrrolidone, polyvinylimidazole, poly-N, N-dimethylacrylamide To cure a monomer comprising a group consisting of polyvinyl alcohol, polyacrylic acid, polyethylene oxide, poly-2-ethyl oxazoline, heparin polysaccharide, polysaccharide, mixtures and copolymers thereof to form an ophthalmic lens. The method further comprises a step. 43. The method of claim 42, wherein washing the ophthalmic lens comprises exposing the ophthalmic lens three times to at least 35 ml of deionized water. 43. The composition of claim 42 wherein N, N-dimethylacrylamide, 2-hydroxyethyl methacrylate, glycerol methacrylate, 2-hydroxyethyl methacrylamide, polyethyleneglycol monomethacrylate, methacrylic acid, acrylic acid, N-vinyl pyrrolidone, N-vinyl-N-methyl acetamide, N-vinyl-N-ethyl acetamide, N-vinyl-N-ethyl formamide, N-vinyl formamide, hydrophilic vinyl carbonate monomer, vinyl carba And curing the monomer comprising a group consisting of a mate monomer, a hydrophilic oxazolone monomer and a polydextran to form an ophthalmic lens. The method of claim 42, wherein the first aqueous solution is heated to about 90 ° C. or higher. 43. The method of claim 42, wherein exposing the ophthalmic lens to a first aqueous solution comprises impregnating the lens with the first aqueous solution. 43. The method of claim 42, wherein exposing the ophthalmic lens to a first aqueous solution comprises flowing the first aqueous solution over the lens.