HK1178488B - Polar thermoplastic opthalmic lens molds, opthalmic lenses molded therein, and related methods - Google Patents

Description

Polar thermoplastic ophthalmic lens molds, ophthalmic lenses molded therein, and related methods

Technical Field

The present invention relates to ophthalmic lens molds comprising at least one polar thermoplastic polymer, ophthalmic lenses cast molded using these polar thermoplastic polymer molds, and related methods. More particularly, the present invention relates to polar thermoplastic polymeric objective lens molds made from materials having an average polarity of about 1% to about 7%, silicone hydrogel contact lenses cast molded using these molds, and methods of making silicone hydrogel contact lenses using these molds.

Background

In a cast molding process for manufacturing ophthalmic lenses, such as contact lenses, a reactive mixture or polymerizable lens precursor composition is cured in a lens-forming cavity defined by a first mold member having a concave lens-forming surface and a second mold member (or female and male mold members, respectively) having a convex lens-forming surface. These mold parts are typically manufactured by injection molding a thermoplastic polymer into a mold cavity. Examples of thermoplastic polymers used to make ophthalmic lens molds include non-polar thermoplastic polymers such as polypropylene, polystyrene, and polyethylene; and polar thermoplastic polymers such as ethylene vinyl alcohol polymers and polyvinyl alcohol polymers. When cast molding a contact lens, after placing the polymerizable composition into the first mold member, the first and second mold members are brought together or coupled together to form a lens assembly having a lens-shaped cavity therebetween. The mold assembly is then cured to polymerize the polymerizable composition, forming a polymerized lens body in the lens-shaped cavity of the mold assembly.

Many different types of thermoplastic polymer materials have been used over the years, including polar and non-polar thermoplastic polymers, to manufacture ophthalmic lenses using various types of polymerizable compositions and using various lens manufacturing processes, including spin casting, lathing, and cast molding.

One example, U.S. patent No. 4,921,205 to deru jr. (Drew, Jr) et al, describes a method of manufacturing and machining a lens blank (lens blank) to form a soft or hard gas permeable contact lens. The method of derurjr specifically involves formulating the material for the mold member so that the lens blank adheres firmly to the mold member after curing. The method includes forming a mold part; casting a polymerizable lens blank into a mold part; curing the lens blank in the mold part to produce a unitary blank-mold part structure; and machining the one-piece blank-mold component structure by first machining away the softer mold component to expose the lens blank, and then machining the lens blank to form the lens. Delu jr. et al lists many types of conventional soft lens materials and rigid gas permeable lens materials that can be used in accordance with the disclosure, but does not discuss any silicone hydrogel materials. While delujr et al list many types of polymers that can be used in the mold parts, including polybutylene terephthalate (PBT), it has been found that polar and non-polar mold materials are also useful when used in the process. Due to the manufacturing procedure used, the wettability of the lens surface is not affected by the choice of thermoplastic polymer used for the mold, since both the mold area used to mold the lens surface and the lens surface that directly contacts the mold part are machined away in the process of forming the lens.

Another example, U.S. patent No. 6,075,066 to Matsuda et al, describes soft contact lenses made by crosslinking glycosaminoglycans in plastic molds, such as PBT molds, using light irradiation. The manufacturing methods described in Songta et al include cut polishing (cutpolising), spin casting, pressing and molding, with spin casting being particularly preferred. In the spin-cast manufacturing method, after the lens-forming material is crosslinked in the mold using UV light, the lens and the mold are immersed in an aqueous solution to swell the lens, thereby enabling it to be released from the single mold part used in the spin-casting method. For such a lens material (crosslinked glycosaminoglycan), the wettability of the lens surface is caused by the properties of the lens material itself, and is correlated with the Degree of Substitution (DS) of the photoreactive group in the glycosaminoglycan. This is illustrated in experimental example 1, which lists the DS of the polymerizable material and the wettability of the resulting lens as determined by measuring advancing and receding contact angles. Thus, the choice of mold material in Songtian et al does not affect the wettability of the resulting lens.

U.S. patent No. 6,997,428 to andeno (Andino) et al is directed to a contact lens mold made from a first UV transparent portion that molds an optical surface of a lens and a second UV opaque portion that does not mold an optical surface of a lens. Andenot et al disclose the use of non-polar and polar thermoplastic polymers, including PBT and acetals, in lens mold sections. Andenot et al do not discuss any preference for mold materials other than those that exhibit good adhesion to each other when used to form a single mold member, do not discuss any type of lens material such as silicone hydrogels, and do not discuss the wettability of lenses made using the mold materials.

When contact lens molds made from non-polar thermoplastic polymers such as polypropylene or polystyrene are used to cast mold silicone hydrogel contact lenses, it is known that additional measures are often required to provide an ophthalmically acceptable wettability of the lens surface. For example, a surface treatment such as a plasma treatment may be applied to the lens surface as part of the manufacturing process. Alternatively, the polymeric interpenetrating network wetting agent can be incorporated into the lens body as part of the manufacturing process to provide the lens body with ophthalmically acceptable wettability.

Recently, it has been found that cast molding silicone hydrogel contact lenses in molds made from highly polar thermoplastic polymers, such as ethylene vinyl alcohol (EVOH) copolymers, e.g., SOARLITE, can produce lenses having ophthalmically acceptably wettable surfaces^TMS (EVOH copolymer polar resin having an average polarity of about 10% to about 12% obtained from Japan synthetic chemical industry Ltd, Osaka (Japan)). Heretofore, when molding with non-polar thermoplastic polymers, it has been necessary to apply a surface treatment, such as a plasma treatment, or to include an interpenetrating network of a polymeric wetting agent in silicone hydrogel contact lenses to provide an ophthalmically acceptable wettability of the lens surface upon hydration. The use of contact lens molds comprising these highly polar thermoplastic polymers (i.e., thermoplastic polymers having an average polarity of greater than or equal to 9%, such as greater than or equal to 10%, greater than or equal to 12%, greater than or equal to 15%, etc.) makes it possible to manufacture wettable silicone hydrogel contact lenses without the need for surface treatments or having interpenetrating networks of polymeric wetting agents in the lens body. However, these highly polar thermoplastic polymers (e.g., EVOH) are expensive materials that can adversely affect manufacturing costs. Molds made from EVOH are generally harder and more brittle than is desirable, which can adversely affect lens yield. In addition, due to the high levels of adhesion typically seen between EVOH molds and silicone hydrogels, a mold set of silicone hydrogel contact lens bodies (containlens bodies) in EVOH-containing mold membersUpon curing in the assembly, mold assembly separation, which separates the two mold members of the mold assembly, typically requires a "wet" demolding process, i.e., a demolding process that involves applying a liquid to the mold assembly containing the polymerized lens body to separate the two mold members, leaving the lens body in contact with one and only one of the two mold members. It is believed that the high adhesion levels observed between EVOH molds and silicone hydrogels are due at least in part to the fact that: EVOH is an elastomeric thermoplastic. Furthermore, following wet demolding, it may be desirable to expose the silicone hydrogel lens body to an additional amount of liquid during the "wet" delensing process in order to release the lens body from one of the retained EVOH mold parts that it remains in contact after the demolding step. In addition, silicone hydrogel contact lenses often require the use of organic solvent-based washing processes to impart ophthalmically acceptable wettability to the lenses, thereby further increasing material, equipment, and manufacturing costs.

In view of the foregoing, it can be appreciated that there is a need for contact lens molds comprising novel material types for cast molding silicone hydrogel ophthalmic lenses, novel silicone hydrogel ophthalmic lenses cast molded using molds comprising these novel material types, and associated methods of manufacture using less expensive, more process-friendly molding materials that do not require the use of expensive processing steps, such as "wet" demolding steps, both "wet" demolding steps and "wet" delensing steps, or organic solvent-based washing steps, and that can produce high yield silicone hydrogel lens bodies having ophthalmically acceptably wettable surfaces without the need for the application of surface treatments or the presence of interpenetrating networks (IPNs) of polymeric wetting agents in the lens bodies.

All publications, including patents, published patent applications, scientific or commercial publications, etc., cited in this specification are herein incorporated by reference in their entirety.

Disclosure of Invention

In a first example, the present invention is directed to a method of manufacturing an ophthalmic lens. In one example, the method is a method of manufacturing a silicone hydrogel contact lens body, the method comprising providing a first mold member and a second mold member, the first mold member comprising a concave molding surface configured to mold an anterior surface of a contact lens and the second mold member comprising a convex molding surface configured to mold a posterior surface of a contact lens, at least one of the first mold member and the second mold member comprising at least one polar thermoplastic polymer having an average polarity of from about 1% to about 7%, the first mold member and the second mold member configured to form a lens-shaped cavity when combined as a mold assembly; placing a polymerizable composition into the first mold member, the polymerizable composition comprising a) at least one silicone monomer, silicone macromer, silicone prepolymer, or combination thereof, and b) at least one hydrophilic monomer; assembling the mold assembly by placing the second mold member in contact with the first mold member, thereby forming a lens-shaped cavity therebetween, wherein the polymerizable composition is contained in the lens-shaped cavity of the mold assembly; curing the polymerizable composition in the mold assembly to form a cast-molded polymerization reaction product in the lens-shaped cavity of the mold assembly, the polymerization reaction product comprising a silicone hydrogel contact lens body; wherein the lens body has ophthalmically acceptably wettable front and back surfaces without the need for applying a surface treatment to the lens body or the presence of an interpenetrating network (IPN) of a polymeric wetting agent in the lens body.

In one example, the at least one polar thermoplastic polymer may be a polar thermoplastic polymer having an average polarity of from about 0.25% to about 8%, from about 1% to about 7%, from 2% to about 5%, from about 1% to about 4%, or about 3%. In one example, the average polarity of the first mold part is the same as the average polarity of the second mold part. In another example, the average polarity of the first mold member is different from the average polarity of the second mold member.

In another example, the at least one polar thermoplastic polymer may be a non-elastomeric thermoplastic.

The average total surface energy of the at least one polar thermoplastic polymer, the first mold part, the second mold part, the molding surface of at least one mold part (i.e., the area of the mold part used to form the lens surface), or a combination thereof, can be greater than or equal to about 32mN/m, greater than or equal to about 35mN/m, greater than or equal to about 37mN/m, from about 32mN/m to about 50mN/m, from about 32mN/m to about 42mN/m, or from about 35mN/m to about 42 mN/m.

The at least one polar thermoplastic polymer, the first mold member, the second mold member, the molding surface of at least one mold member, or a combination thereof can have a glass transition temperature that is lower than the temperature used to thermally cure the lens body. For example, the polar thermoplastic polymer may have a glass transition temperature of less than about 90 ℃, less than about 70 ℃, less than about 60 ℃, less than about 50 ℃, or about 45 ℃.

The at least one polar thermoplastic polymer, the first mold part, the second mold part, or a combination thereof can comprise, consist essentially of, or consist of polybutylene terephthalate (PBT).

The at least one polar thermoplastic polymer, the first mold component, the second mold component, the molding surface of at least one mold component, or a combination thereof can comprise, include, consist essentially of, or consist of polyacetal (acetal).

The at least one polar thermoplastic polymer, the first mold member, the second mold member, the molding surface of at least one mold member, or a combination thereof can comprise a mixture of at least one polar thermoplastic polymer and at least one additive. The at least one additive can include an additive that enables dry demolding, dry delensing, or both dry demolding and dry delensing of the cured silicone hydrogel contact lens body without having to contact the mold assembly, the mold member with which the lens body is in contact, or the lens body with a liquid. The at least one additive may comprise a fatty acid, a fatty acid ester, a metal salt of a fatty acid, or a combination thereof.

The at least one polar thermoplastic polymer, the first mold member, the second mold member, the molding surface of at least one mold member, or a combination thereof can comprise, include, consist essentially of, or consist of a mixture of at least one polar thermoplastic polymer and at least one non-thermoplastic polymer, wherein the average polarity of the mixture is from about 0.25% to about 8%, such as from about 1% to about 7%, from 2% to about 5%, from about 1% to about 4%, or about 3%. The at least one polar thermoplastic polymer in the mixture may be a polar thermoplastic polymer having an average polarity of from about 0.25% to about 8%, or the at least one polar thermoplastic polymer may be a polar thermoplastic polymer having an average polarity of greater than 9%.

In other examples, the polymerizable composition can have an average polarity of about 0.25% to about 8%, about 1% to about 7%, about 2% to about 7%, about 3% to about 6%, or about 5%.

The spreading coefficient can be greater than or equal to about 13mN/m, from about 13mN/m to about 18mN/m, or from about 12mN/m to about 15mN/m when the polymerizable composition is in contact with the molding surface of the mold member.

After curing the polymerizable composition in a mold assembly comprising first and second mold members of a polar thermoplastic polymer, the mold assembly can have an average adhesion energy of greater than or equal to about 55mJ/m²Greater than or equal to about 58mJ/m²And is about 40mJ/m²To about 70mJ/m²Is about 50mJ/m²To about 65mJ/m²Is about 55mJ/m²To about 63mJ/m²Or about 58mJ/m²To about 61mJ/m²。

The method of manufacturing an ophthalmic lens can further comprise the step of separating the mold assembly, wherein the separation causes the lens body to remain in contact with one and only one of the first mold member and the second mold member. In a demolding process, separation of the mold assembly is such that the lens body remains in contact with one and only one of the first mold member and the second mold member in the mold assembly. In other words, prior to the demolding process, the lens body contacts both the first mold member and the second mold member, while after the demolding process, the lens body remains in contact with only one of the two mold members, wherein the one mold member with which the lens body remains in contact can be the first mold member or the second mold member.

In one example, the step of separating the mold assembly includes using a dry demolding process that does not involve applying a liquid to the mold assembly containing the lens body. In other words, the dry demolding process does not contact the mold assembly including the lens body with a liquid. The dry demolding step often uses mechanical methods to separate the mold members of the mold assembly.

In one example, the method of manufacturing an ophthalmic lens can further include the step of applying heat or cold to one of the first mold member and the second mold member in the mold assembly immediately prior to or simultaneously with the step of separating the mold assembly using a dry demolding process. The step of applying heat or cold to one of the first and second molding members used to mold the lens body can be used to increase the number of lens bodies that remain in contact with a particular desired mold member after demolding. For example, applying heat to the male mold member can increase the number of lens bodies that remain in contact with the female mold member after the demolding process. Depending on the method to be used to delensing the lens body, it may be desirable or necessary to keep the lens body in contact with a particular one of the two mold members of the mold assembly.

In another example, the step of separating the mold assembly includes using a wet demolding process, which involves applying a liquid to the mold assembly containing the lens body. In other words, the wet demolding process contacts the mold assembly including the lens body with a liquid. In one example, the wet demolding process can be a combined wet demolding/delensing process that involves applying a liquid to a mold assembly containing a lens body and separating two mold members in the mold assembly and releasing the lens body from the first and second mold members. In another example, a wet demolding process or a combined wet demolding/delensing process may optionally involve applying ultrasonic energy to the liquid and the mold assembly.

The method of manufacturing an ophthalmic lens can further comprise the step of releasing the lens body from one and only one of the first mold member and the second mold member with which the lens body remains in contact after the demolding process, thereby forming a delensed lens body.

The delensing process can include a wet delensing process, i.e., a delensing process involving applying a liquid to the lens body and one mold member with which the lens body remains in contact after the demolding process. In one example of a wet delensing process, ultrasonic energy can be applied to the liquid and lens body during delensing.

Alternatively, the delensing process can include a dry delensing process involving releasing the lens body from one and only one of the first mold member and the second mold member using a method that does not involve applying a liquid to the lens body. For example, a dry demolding process may include mechanically deforming the one mold member to at least partially break or loosen the bond or adhesion between the lens body and the one mold member. In one example, the method of dry delensing a lens body does not involve lathing or grinding away one and only one of the first mold member and the second mold member to release the lens body, thereby forming a delensed lens body.

In one example, the method of manufacturing an ophthalmic lens further comprises the step of washing the released lens body. The step of washing the released lens body can comprise washing the lens body to remove dust or debris, extracting material from the lens body, hydrating the lens body, and/or combinations thereof. The extracted species can include unreacted monomers, partially reacted monomers, and/or unreactive (non-polymerizable) components, and the like, as well as combinations and subsets thereof, in the polymerizable composition. One or more washing steps may be used. The liquid used in a single washing step can comprise a pure organic solvent, an organic solvent solution, or can comprise an aqueous solution substantially free of an organic solvent to produce a washed lens body. When more than one washing step is used, the wash liquor in each washing step may have the same or different composition.

In another example, in the method of manufacturing an ophthalmic lens, the step of providing a first mold member and a second mold member can comprise the step of forming the first mold member and the second mold member. The first mold member and/or the second mold member may be formed entirely by injection molding. Alternatively, the first mold member and/or the second mold member may be formed by a combination of injection molding, lathing, cutting, or any combination thereof. For example, a mold member formed by a combination of injection molding and lathing or cutting may comprise the basic shape of a mold prepared by injection molding, after which all or part of the optical molding surface of the mold (all or part of the area of the mold used to form the optical zone of the contact lens) may be lathed or cut into a mold member of the desired design.

In another example, the method of manufacturing an ophthalmic lens comprises a method of manufacturing an ophthalmic lens entirely by cast molding. For example, after cast molding, demolding or delensing, the lens body is not lathed.

In one example of the method of manufacturing an ophthalmic lens, the polymerizable composition can further comprise a UV initiator, and the step of curing the polymerizable composition in the mold assembly can comprise applying UV light to polymerize the polymerizable composition. Alternatively, the polymerizable composition can further comprise a thermal initiator, and the step of curing the polymerizable composition in the mold assembly can comprise applying thermal radiation to polymerize the polymerizable composition. In one example, when curing comprises applying thermal radiation, the thermal radiation used to polymerize the lens body can be conducted at a temperature below the glass transition temperature of the polar thermoplastic polymer.

The ophthalmic lenses made using the method of the present invention are ophthalmically acceptable wettable ophthalmic lenses. When fully hydrated, the lens may have a water break-up time (WBUT) of greater than or equal to about 5 seconds, greater than or equal to about 10 seconds, greater than or equal to about 15 seconds, greater than or equal to about 20 seconds, greater than or equal to about 30 seconds, greater than or equal to about 40 seconds, or greater than or equal to about 50 seconds.

When fully hydrated, the contact angle of the lens can be less than or equal to about 120 °, less than or equal to about 90 °, less than or equal to about 80 °, less than or equal to about 60 °, less than or equal to about 50 °, less than or equal to about 40 °, less than or equal to about 30 °, or from about 10 ° to about 30 °. In one example, the contact angle may be measured using the sessiledropmethod.

In another example of the method of manufacturing an ophthalmic lens, the method produces a yield of acceptable lens bodies that is higher than a yield of acceptable lens bodies manufactured using substantially the same method but using first and second mold members comprising a polar thermoplastic polymer having an average polarity greater than or equal to 9%. The polar thermoplastic polymer having an average polarity of greater than or equal to 9% can be an ethylene-vinyl alcohol copolymer. The yield of acceptable lens bodies can be a yield of cosmetically acceptable lenses, or a yield of ophthalmically acceptable lenses. The yield of acceptable lenses can be that of lenses found to be free of visually detectable defects, as determined by manual visual inspection or by automated inspection using an automated inspection system. The yield of acceptable lens bodies can be the yield of acceptable lenses resulting from particular processing steps such as curing steps, demolding steps, delensing steps, washing steps, packaging steps, combinations of processing steps, and the like.

The present invention is also directed to a silicone hydrogel contact lens body comprising a cast-molded polymerized lens body comprising the reaction product of a polymerizable composition comprising a) at least one silicone monomer, silicone macromer, silicone prepolymer, or combination thereof, and b) at least one hydrophilic monomer; wherein the lens body is cast molded in a mold assembly comprising a first mold member and a second mold member, at least one of the first mold member and the second mold member comprising at least one polar thermoplastic polymer material having an average polarity of about 1% to about 7%; and the lens body has ophthalmically acceptably wettable front and back surfaces without the need for applying a surface treatment to the lens body or the presence of an interpenetrating network (IPN) of a polymeric wetting agent in the lens body.

The polymerizable composition can further comprise a silicone oil form. The silicone oil can be in the form of a water-soluble silicone oil, or can be a polymerizable silicone oil.

The polymerizable composition may further comprise a thermal initiator, a UV initiator, or both a thermal initiator and a UV initiator.

The polymerizable composition may further comprise a colorant, a UV blocker, or both a colorant and a UV blocker.

The polymerizable composition may be a polymerizable composition for forming a camifacie a (comfilcon a) lens, and the lens body is a camifacie a lens body.

The hydrophilic monomer in the polymerizable composition can be a hydrophilic monomer having an N-vinyl group.

In one example, the polymerizable composition can be one in which at least one of a) at least one silicone monomer, silicone macromer, silicone prepolymer, or combination thereof, and b) at least one hydrophilic monomer comprises a first monomer having a first reactivity ratio, and at least another of a) at least one silicone monomer, silicone macromer, silicone prepolymer, or combination thereof, and b) at least one hydrophilic monomer comprises a second monomer having a second reactivity ratio that is lower than the first reactivity ratio. In another example, the polymerizable composition can further comprise at least one crosslinker having a reactivity ratio similar to the first reactivity ratio or the second reactivity ratio. In another example, the polymerizable composition can include at least two crosslinkers, a first crosslinker having a reactivity ratio similar to the first reactivity ratio and a second crosslinker having a reactivity ratio similar to the second reactivity ratio.

The average polarity of the polymerizable composition can be about 1% to about 7%, about 3% to about 6%, or about 5%.

The spreading coefficient can be greater than or equal to about 13mN/m, from about 13mN/m to about 18mN/m, or from about 12mN/m to about 15mN/m when the polymerizable composition is in contact with the molding surface of the polar thermoplastic mold member.

After curing the polymerizable composition in a mold assembly comprising at least one mold member comprising at least one polar thermoplastic polymer, the mold assembly has an average adhesion energy of greater than or equal to about 55mJ/m²Greater than or equal to about 58mJ/m²Is about 55mJ/m²To about 63mJ/m²Or about 58mJ/m²To about 61mJ/m²。

Mold assemblies containing polymerized silicone hydrogel contact lens bodies can be separated using a dry demolding method that does not involve applying a liquid to the mold assembly containing the lens body, wherein the separation results in the lens body remaining in contact with one and only one of the first mold member and the second mold member, i.e., the demolded mold member and lens body. Alternatively, mold assemblies containing polymerized silicone hydrogel contact lens bodies can be separated using a wet demolding method that involves applying a liquid to the mold assembly containing the lens body.

After demolding the mold assembly, the silicone hydrogel contact lens body can be delensed, i.e., released from one mold member that it remains in contact after the demolding process, using a wet delensing method that involves applying a liquid to the demolded mold member and lens body. Alternatively, silicone hydrogel contact lens bodies can be delensed using a dry delensing method that does not involve the application of a liquid to the demolded mold member and lens body. The delensing process produces a delensing lens body.

After dry demolding and dry delensing, the silicone hydrogel contact lens body can be washed to clean dust or debris in the lens body as part of a wet delensing process or in addition to a de-wetting delensing process; extracting a substance from a lens body; hydrating the lens body; and combinations thereof. One or more wash steps may be performed on the lens body. The liquid used to wash the lens body in a single washing step may comprise a pure organic solvent, an organic solvent solution, or an aqueous solution substantially free of organic solvent. When more than one washing step is used, the liquids used in each step may have the same or different compositions.

After the demolding, delensing, and optional washing steps, the silicone hydrogel contact lens bodies (i.e., the lens bodies that have been demolded, delensed, and washed) can be combined with a packaging solution into a package, sealed, and sterilized, thereby forming a packaged contact lens product. The lens body may be hydrated prior to packaging or may become fully hydrated during the packaging, sealing and sterilization processes. When one or more optional washing steps are used, and the last washing step employs an aqueous solution substantially free of organic solvent, the substantially organic solvent-free aqueous solution can be used as a packaging solution.

At least one of the first and second mold members, both of the first and second mold members, at least one molding surface of the first or second mold members, or molding surfaces of both of the first and second mold members used to form the silicone hydrogel contact lens body can comprise at least one polar thermoplastic polymer material having an average polarity of, for example, from about 0.25% to about 8%, from about 1% to about 7%, from 2% to about 5%, from about 1% to about 4%, or about 3%; or may have an average polarity of, for example, about 0.25% to about 8%, about 1% to about 7%, 2% to about 5%, about 1% to about 4%, or about 3%.

The average total surface energy of the at least one polar thermoplastic polymer of at least one of the first and second mold members or both the first and second mold members can be greater than or equal to about 32mN/m, from about 32mN/m to about 50mN/m, or from about 32mN/m to about 42 mN/m. The average total surface energy of the at least one polar thermoplastic polymer can be determined in the region of a mold member used to mold the optical surface of a contact lens.

The glass transition temperature of the at least one polar thermoplastic polymer of at least one of the first and second mold members or both the first and second mold members may be less than about 90 ℃, less than about 70 ℃, less than about 60 ℃, less than about 50 ℃, or about 45 ℃.

The at least one polar thermoplastic polymer of at least one of the first and second mold members or both the first and second mold members may comprise, consist essentially of, or consist of polybutylene terephthalate (PBT).

The polar thermoplastic polymer of at least one of the first and second mold members or both the first and second mold members may comprise, consist essentially of, or consist of polyacetal (acetal).

Silicone hydrogel contact lenses are ophthalmically acceptable wettable contact lenses. When fully hydrated, the lens can have a water break time (WBUT) of greater than or equal to about 5 seconds, greater than or equal to about 10 seconds, greater than or equal to about 15 seconds, greater than or equal to about 20 seconds, greater than or equal to about 30 seconds, greater than or equal to about 40 seconds, or greater than or equal to about 50 seconds.

When fully hydrated, the contact angle of the lens can be less than or equal to about 120 °, less than or equal to about 90 °, less than or equal to about 80 °, less than or equal to about 60 °, less than or equal to about 50 °, less than or equal to about 40 °, less than or equal to about 30 °, or from about 10 ° to about 30 °. In one example, the contact angle may be measured using a sessile drop method.

In one example, the silicone hydrogel contact lens is a silicone hydrogel lens body that is less defective than a contact lens body made using substantially the same polymerizable composition but molding in first and second mold members having molding surfaces with an average polarity greater than or equal to 9%. In one example, the first and second mold parts can consist essentially of a polar thermoplastic polymer having an average polarity of greater than or equal to 9%. The polar thermoplastic polymer having an average polarity of greater than or equal to 9% can be an ethylene-vinyl alcohol copolymer, such as SOARLITE^TMS。

The present invention is also directed to a mold member for cast molding an ophthalmic lens body, wherein the mold member, the molding surface of the mold member, or both comprise at least one polar thermoplastic polymer having an average polarity of about 1% to about 7%. The ophthalmic lens body can be a silicone hydrogel contact lens body.

The average polarity of the at least one polar thermoplastic polymer of the mold member, the molding surface, or both, can be from about 0.25% to about 8%, from about 1% to about 7%, from about 2% to about 5%, from about 1% to about 4%, or about 3%.

The average total surface energy of the at least one polar thermoplastic polymer of the mold member, the molding surface, or both, can be greater than or equal to about 32mN/m, from about 32mN/m to about 50mN/m, or from about 32mN/m to about 42 mN/m. The average total surface energy of the polar thermoplastic polymer can be determined in the region of the mold member used to mold the optical surface of the contact lens.

The at least one polar thermoplastic polymer of the mold member, the molding surface, or both, can have a glass transition temperature of less than or equal to about 90 ℃, less than or equal to about 70 ℃, less than or equal to about 60 ℃, less than or equal to about 50 ℃, or about 45 ℃.

The at least one polar thermoplastic polymer of the mold part, the molding surface, or both, can comprise, consist essentially of, or consist of PBT.

The at least one polar thermoplastic polymer of the mold member, the molding surface, or both may comprise, consist essentially of, or consist of an acetal.

In one example, the mold member, the molding surface of the mold member, or both, can further comprise a non-polar thermoplastic polymer, such as polypropylene.

In another example, the mold member, the molding surface of the mold member, or both, can comprise, consist essentially of, or consist of a mixture of at least one polar thermoplastic polymer and at least one non-thermoplastic polymer, wherein the average polarity of the mixture is from about 0.25% to about 8%, such as from about 1% to about 7%, from 2% to about 5%, from about 1% to about 4%, or about 3%. The at least one polar thermoplastic polymer in the mixture may be a polar thermoplastic polymer having an average polarity of from about 0.25% to about 8%, or the at least one polar thermoplastic polymer may be a polar thermoplastic polymer having an average polarity of greater than 9%.

In another example, the mold member can be formed by injection molding. In one example, during injection molding, the mold tool used to form the mold member may be maintained at a temperature of about 30 ℃ to about 70 ℃. In another example, the one or more conditions for injection molding the mold member are selected from the group consisting of: a melt temperature of about 245 ℃ and about 270 ℃, a hold temperature of about 235 ℃ to about 270 ℃, a feed temperature of about 235 ℃ to about 250 ℃, a hold pressure of about 60 bar (bar) to about 125 bar, and an ejection velocity through about 3mm orifices of about 50mm/sec to about 125 mm/sec.

The present invention is also directed to a method of manufacturing a silicone hydrogel contact lens body, comprising: curing the silicone-containing polymerizable composition in a mold assembly comprising at least one mold member formed from a thermoplastic polymer comprising polybutylene terephthalate (PBT), thereby forming a lens-shaped cast-molded polymeric reaction product comprising a silicone hydrogel contact lens body. In one example, the silicone hydrogel contact lens body has ophthalmically acceptably wettable cast molded anterior and posterior surfaces without the need for applying a surface treatment to the lens body or the presence of an interpenetrating network (IPN) of a polymeric wetting agent in the lens body. Upon hydration, the silicone hydrogel contact lens body has an advancing contact angle of less than about 100 °. In another example, the thermoplastic polymer comprising polybutylene terephthalate (PBT) further comprises at least one additive selected from the group consisting of: fatty acids, fatty acid esters, metal salts of fatty acids, and combinations thereof.

Any and all combinations of the foregoing or following aspects/embodiments/features and the aspects/embodiments/features set out in the claims, sentences or paragraphs are included within the scope of the present application as long as the aspects/embodiments/features in any such combination in any such order are not mutually inconsistent. Moreover, any aspect/embodiment/feature or combination of aspects/embodiments/features may be specifically excluded from any example of the present invention.

Drawings

Fig. 1 is a flow chart illustrating the steps of a method for manufacturing an ophthalmic lens.

Fig. 2 is a flow diagram illustrating certain inputs and outputs of the method of fig. 1, including a polymerizable composition, a polymerized lens body that has not been contacted with a liquid, a hydrated lens body, and a packaged ophthalmic lens.

Detailed Description

Ophthalmic lens molds made substantially from highly polar thermoplastic polymers (i.e., thermoplastic polymers having an average polarity greater than or equal to 9%) have been used to cast mold silicone hydrogel lens bodies. The molding surface of the lens mold (i.e., the mold part area used to form the lens surface) also has an average polarity of greater than or equal to 9%. Unlike molds and molding surfaces made from non-polar materials, it has been found that molds and molding surfaces made from highly polar thermoplastic polymers produce lens bodies having ophthalmically acceptably wettable surfaces without the need to apply a surface treatment to the lens surface and without the use of an interpenetrating network of a polymeric wetting agent in the lens body. These highly polar thermoplastic polymers include EVOH copolymers, such as SOARLITE^TMS。

Silicone hydrogel lens bodies having ophthalmically acceptably wettable lens surfaces can also be cast molded using lower polarity thermoplastic polymers, i.e., thermoplastic polymers having an average polarity of about 1% to about 7%, without applying a surface treatment to the lens surface and without using an interpenetrating network of a polymeric wetting agent in the lens body. In one example, these less polar thermoplastic polymers are non-elastomeric thermoplastics, i.e., the non-elastomeric thermoplastics do not return to their original shape when the deforming force is removed.

Even more surprisingly, silicone hydrogel contact lenses can be cast molded using these less polar thermoplastic polymers, using dry demolding methods, dry delensing methods, or both dry demolding and delensing methods, i.e., demolding, delensing, or both demolding and delensing processes that do not involve the application of a liquid to the polymerized lens body and the mold assembly or mold member, as opposed to utilizing highly polar polymer mold materials.

By using a mold member comprising a less polar thermoplastic polymer in combination with a polymerizable silicone hydrogel lens-forming composition, the resulting polymerized lens body is more wettable than the same polymerizable composition molded using a mold member comprising a highly polar thermoplastic polymer mold member (e.g., EVOH). In one example, using a polymerizable composition having an average polarity in about the same range as the lower polarity thermoplastic polymer of the mold member (e.g., about 1% to about 7%) results in a more wettable, polymerized lens body after curing, as compared to the same polymerizable composition and utilizing a high polarity thermoplastic polymer mold member (e.g., an average polarity greater than or equal to 9%). In another example, using a polymerizable composition having an average polarity in about the same range as the less polar thermoplastic polymer of the mold member (e.g., about 1% to about 7%) the spreading factor between the polymerizable composition and the mold member is higher compared to the spreading factor between the same polymerizable composition and the highly polar thermoplastic polymer mold member. The polarity of the polymerizable composition and the polarity of the mold member can both be from about 1% to about 7%. The polarity of the polymerizable composition can be in the range of 6 percentage points of the polarity of the mold member (e.g., the polarity of the polymerizable composition can be about 1% and the polarity of the mold member can be about 7%). Similarly, the polarity of the polymerizable composition can be in a range of about 5 percentage points, about 4 percentage points, about 3 percentage points, about 2 percentage points, or about 1 percentage point of the polarity of the mold member. Alternatively, the polarity of the polymerizable composition can be about the same as the polarity of the mold member (e.g., the polarity of both the polymerizable composition and the mold member can be about 1%, about 2%, about 3%, about 4%, about 5%, about 6%, or about 7%).

When using mold members comprising a less polar thermoplastic polymer having a glass transition temperature of less than about 90 ℃, curing the polymerizable composition in the mold assemblies made from these mold members comprising the less polar thermoplastic polymer, wherein curing is achieved using thermal radiation at a temperature below the glass transition temperature of the less polar thermoplastic polymer, produces a polymerized lens body that can be demolded, delensed, or both demolded and delensed from the mold members using a dry process (i.e., a process that does not require application of a liquid to the lens body and the mold members).

Examples of lower polarity thermoplastic polymers that may be used to form mold members for molding ophthalmic lenses include, but are not limited to, polybutylene terephthalate (PBT) and polyacetal (acetal). Polybutylene terephthalate (a type of polyester) is a semi-crystalline thermoplastic polymer. PBT is typically produced by the polymerization of butanediol with terephthalic acid. The homopolymer form of PBT has a melting point of about 223 ℃ and a glass transition temperature of about 60 ℃, but these values may vary slightly based on the manufacturer of the material, the grade of material used, the method and heating rate used, and the like. Both homopolymer and copolymer forms of PBT are suitable for injection molding and for use as described herein.

Acetal is a form of polyoxymethylene plastic. It is a semi-crystalline polymer, with a melting point of about 175 ℃ in homopolymer form and a glass transition temperature of about-60 ℃, although these values may vary slightly based on the manufacturer of the material, the grade of material used, the method used, the rate of heating, and the like. Like PBT, both homopolymer and copolymer forms are suitable for injection molding and for use as described herein.

The less polar thermoplastic polymers described herein can include one or more of any suitable polar groups. Of course, the polymer should be suitable for shaping (e.g., injection molding, etc.) into an ophthalmic lens mold member useful in the manufacture of ophthalmic lenses (e.g., contact lenses, intraocular lenses (intracamerales), corneal inlays (corneal inlays), corneal onlays (corneal onlays), etc.). Examples of the polar group include, but are not limited to, a hydroxyl group (-OH), a carboxyl group (-COOH), an amino group (-NH )₂) Acyl ofAmino (-CONH)₂、-(RCO)₂NH、-(RCO)₃N) and nitro (-NO)₂)。

The less polar thermoplastic polymers used in the devices and methods described herein can have an average polarity of about 1% to about 7%, an average polarity of about 2% to about 5%, or an average polarity of about 1% to about 4%. The average polarity of the less polar thermoplastic polymer can be determined using one or more standard tests or assays that are conventional and well known in the polymer art. One method of determining polarity is based on the Owens-Wendt-Rabel-kaebel model (Owens-Wendt-Rabel-kaebel model), in which the contact angle of a thermoplastic polymer is determined using a variety of different liquids of known polarity. The owens-wendt-rabel-kaebel equation can be written in the form of a linear equation, where y is calculated based on the observed contact angle (θ) of each different liquid with the polymer, and x is based on the total surface energy (σ) of each different liquid_L ^T) Of known polarity (σ)_L ^P) And dispersion (σ)_L ^D) And (4) component calculation. The data points (x, y) obtained from different liquids can be plotted and then the slope (m) and y-intercept (b) can be determined using linear regression of the plot. The calculated slope and y-intercept can then be used to calculate the total surface energy (σ) of the polar thermoplastic polymer_S ^TWhere σ is_S ^T＝σ_S ^P+σ_S ^D) Polarity (σ) of (C)_S ^P) And dispersion (σ)_S ^D) And (4) components.

An owens-wentt-rabel-kaebel equation in the form of a linear equation:

whereinAnd is

Examples of liquids with different polarities that can be used to determine the average polarity of the thermoplastic polymer include, but are not limited to, deionized water, diiodomethane, dimethyl sulfoxide (DMSO), and formamide. In selecting liquids with different polarities, it is desirable that the polar component (σ) based on the total surface energy of the liquids should be based on_L ^P) Selecting a plurality of liquids having a plurality of polarities rather than different total surface energies (σ)_L ^T) A plurality of liquids. Using this method, the polar component (σ) is calculated by using the total surface energy of the polymer_S ^P) Divided by its calculated total surface energy (σ)_S ^T) And multiplied by 100 to obtain the percent polarity to calculate the average polarity of the thermoplastic polymer.

The average total surface energy of the less polar thermoplastic polymers used in the apparatus and methods described herein can be less than or equal to about 32mN/m, from about 32mN/m to about 50mN/m, or from about 32mN/m to about 42 mN/m. The average total surface energy can be determined using one or more standard tests or analyses (including by procedures based on the owens-wendt-rabel-kaebel model described above) that are conventional and well known in the polymer art.

Alternatively or additionally, the lower polarity thermoplastic polymers described herein, including the molding surface of the polymeric mold member (i.e., the mold member region of the surface used to form the lens body), can also have specific characteristics.

Depending on the form and grade of the less polar thermoplastic polymer used, the polymer may have a glass transition temperature of less than about 90 ℃. For example, the less polar thermoplastic polymer may have a glass transition temperature of less than about 70 ℃, less than about 60 ℃, less than about 50 ℃, or about 45 ℃. The glass transition temperature may be determined using one or more standard tests or assays that are conventional and well known in the polymer art. For example, the glass transition temperature can be determined using dilatometry, calorimetry (e.g., differential scanning calorimetry, DSC), and using standard test methods such as ISO11357-1, ISO11357-2, or ISO11357-3, at a specified heating rate of, for example, 10 ℃/min.

In one example, the average polarity of the polymerizable composition for use with one or more mold members comprising a less polar thermoplastic polymer can be from about 1% to about 7%, from about 2% to about 7%, from about 3% to about 6%, or about 5%. The average polarity of the polymerizable composition can be determined using one or more standard tests or assays that are conventional and well known in the polymer art. For example, the average polarity of the polymerizable composition can be calculated using: (a) total surface tension (σ) of the polymerizable composition as determined by the pendant drop method_L ^T) And (b) a dispersion component (σ) of the total surface tension of the polymerizable composition calculated by measuring a contact angle (θ) of the polymerizable composition on Teflon (polytetrafluoroethylene, PTFE) using the following equation_L ^D)：

Equation σ may then be used_L ^P＝σ_L ^T-σ_L ^DUsing the measured total surface tension (σ)_L ^T) Subtracting the measured dispersion component (σ) of the total surface tension_L ^D) To obtain the polar component of the surface tension. By using a polar component (σ)_L ^P) Divided by the total surface energy (σ)_L ^T) And multiplied by 100 to calculate the average polarity of the polymerizable composition.

In another example, the spreading factor of the polymerizable composition and the mold member can be greater than or equal to about 13mN/m, can be from about 13mN/m to about 18mN/m, or from about 12mN/m to about 15mN/m when the polymerizable composition described herein is placed in contact with a mold member comprising a less polar thermoplastic polymer described herein. The spreading factor of the polymerizable composition and the less polar thermoplastic polymer can be determined using one or more standard tests or assays that are conventional and well known in the polymer art. For example, it may be based on the surface energy (σ) of the mold part_S) Surface energy (σ) of polymerizable composition_L) And interfacial tension (σ) at the interface of the polymerizable composition and the mold member_SL) The spreading factor was determined using the following equation:

spreading coefficient is σ_S-σ_L-σ_SL。

In another example, when the polymerizable composition described herein is cured in a mold assembly comprising first and second mold members comprising a less polar thermoplastic polymer described herein to form a polymerized lens body, the average adhesion energy of the components of the mold assembly (i.e., the first mold member, the second mold member, and the polymerized lens body) can be greater than or equal to about 55mJ/m²Is about 55mJ/m²To about 63mJ/m²Or about 58mJ/m²To about 61mJ/m². The average adhesion energy of the mold assembly can be determined using one or more standard tests or analyses that are conventional and well known in the polymer art. For example, the dispersion component (σ) can be based on the total surface energy of the polymerizable composition_L ^D) Polar component of the total surface energy of the polymerizable composition (σ)_L ^P) The dispersed component of the total surface energy (σ) of the less polar thermoplastic polymer_S ^D) And a polar component (σ) of the total surface energy of the less polar thermoplastic polymer_S ^P) The average adhesion energy was calculated. As previously mentioned, the total surface energy as well as the polar and dispersive components of the surface energy can be calculated based on the owens-wentt-rabel-kaebel model. The adhesion energy of the mold assembly can then be calculated using the following equation:

adhesion energy of 2[ (. sigma. ])_S ^Dσ_L ^D)^1/2+(σ_S ^Pσ_L ^P)^1/2]。

The mold parts described herein may comprise, include, consist essentially of, or consist of the less polar thermoplastic polymers described herein. The mold parts comprising the less polar thermoplastic polymers described herein may further comprise one or more ingredients commonly found in thermoplastic polymer compositions, such as plasticizers, defoamers, antistatic agents, extenders, and the like. The addition of these ingredients, which are commonly found in thermoplastic polymer compositions, can be used to alter the characteristics of, or improve the quality of, mold parts formed from the polymer, including the quality of the molding surface of the mold part. Prior to forming a mold part using a less polar thermoplastic polymer or thermoplastic polymer composition, the polymer or composition may be exposed to a treatment, such as a drying treatment to reduce the water content. The use of these treatments on a polymer or composition can alter the characteristics of, or increase the quality of, a mold part formed from the polymer or composition, including the quality of the molding surface of the mold part.

In one example, the less polar thermoplastic polymer may comprise a hydrophilic polymer. The less polar thermoplastic polymer may comprise a mixture comprising one or more polar polymers and one or more non-polar polymers (e.g., non-hydrophilic polymers or hydrophobic polymers). Useful non-polar polymers include polymers that are even less polar (i.e., have a lower polarity) than the less polar thermoplastic polymer included in the one or more mold members. In one example, the non-polar polymer used is at least about 10%, or at least about 30%, or at least about 50%, or at least about 70%, or at least about 90% less polar than the less polar thermoplastic polymer included in the one or more mold members. In one example, the non-polar polymer is substantially non-polar (e.g., about 0.05% or less polar). The selected non-polar polymer or polymers should be compatible with the less polar thermoplastic polymer in order to provide a polymer mixture suitable for use in ophthalmic lens molds and mold parts according to the present invention.

Examples of non-polar polymers that may be used in combination with the less polar thermoplastic polymers according to the present invention include, but are not limited to, polyolefins, preferably selected from polyethylene, polypropylene, polystyrene, and the like, and mixtures thereof. The relative amounts of the less polar thermoplastic polymer and the non-polar polymer in the molds and mold parts of the invention can vary widely and depend on various factors such as the particular less polar thermoplastic polymer used, the particular non-polar polymer used, the particular lens material to be used, the particular lens (mold) design to be obtained, and the like. In one example, the non-polar polymer comprises a minor amount, i.e., less than about 50%, of the weight of the mixture of less polar polymer and non-polar polymer. The non-polar polymer may comprise at least about 5%, about 10%, about 15%, about 20%, about 30%, or about 50% by weight of the mixture of less polar polymer and non-polar polymer. In another example, the non-polar polymer comprises a substantial amount, i.e., greater than about 50%, by weight of the mixture of less polar polymer and non-polar polymer. The non-polar polymer may comprise at least about 50%, about 60%, about 70%, about 80%, or about 90% by weight of the mixture of less polar polymer and non-polar polymer.

The combination of non-polar polymer and polar polymer may be a combination of at least one non-polar polymer and at least one polar polymer, wherein the at least one polar polymer has an average polarity of greater than or equal to 9%, and the average polarity of the combination is from about 0.25% to about 8%, such as from about 1% to about 7%, from 2% to about 5%, from about 1% to about 4%, or about 3%.

The combination of non-polar polymer and polar polymer may be a combination of at least one non-polar polymer and at least one polar polymer, wherein the at least one polar polymer has an average polarity of about 0.25% to about 8%, and the combination has an average polarity of about 0.25% to about 8%, such as about 1% to about 7%, 2% to about 5%, about 1% to about 4%, or about 3%.

The thermoplastic polymer (i.e., the less polar thermoplastic polymer, the non-polar thermoplastic polymer, the polar thermoplastic polymer, and combinations thereof) used to form the mold member, the molding surface, or both described herein can include one or more additives. These additives may be present in the thermoplastic material in the form of a mixture. In one example, these additives can be effective to enable dry demolding, dry delensing, or both dry demolding and delensing of a cured silicone hydrogel contact lens body from a molding surface comprising a thermoplastic polymer and the additive. These additives may be present in the thermoplastic material in the form of a mixture. In another example, the additives can be effective to increase the yield of cosmetically acceptable cured silicone hydrogel contact lens bodies when dry demolded, dry delensed, or both dry demolded and delensed from a molding surface comprising the thermoplastic polymer and the additives as compared to the yield of cosmetically acceptable cured silicone hydrogel contact lens bodies when dry demolded, dry delensed, or both dry demolded and delensed from a substantially identical molding surface in the absence of the additives. In another example, these additives can be effective to reduce the lens deformation rate of a silicone hydrogel contact lens body cured when dry demolded, dry delensed, or both dry demolded and delensed from a molding surface comprising a thermoplastic polymer and the additive as compared to the lens deformation rate of a silicone hydrogel contact lens body cured when dry demolded, dry delensed, or both dry demolded and delensed from a substantially identical molding surface in the absence of the additive.

In one example, the additive present in admixture with the thermoplastic polymer may comprise one or more fatty acid forms, such as free fatty acids, fatty acid esters, metal salts of fatty acids, or combinations thereof. As used herein, a fatty acid is understood to be a long chain alicyclic hydrocarbon (saturated or unsaturated) containing a carboxylic acid end group. The fatty acid may be present in the thermoplastic polymer at a concentration of from about 0.001% to about 10%, from about 0.01% to about 5%, or from about 0.02% to about 3%.

The present mold members can be made by conventional injection molding procedures known to those skilled in the art. For example, some of the polymeric materials disclosed herein may be heated to form a molten thermoplastic polymer. The molten thermoplastic polymer can be dispensed into a mold cavity in the shape of an ophthalmic lens mold. For example, the mold cavity may include one or two optical quality molding surfaces. The optical quality molding surface may be provided as a component of one or more removable inserts located in a flat plate or other housing, or may undergo integral machining as part of the molding cavity. The molten thermoplastic polymer in the mold cavity can then be cooled and separated from the molding machine to move to a location to receive a volume of polymerizable composition. Alternatively, the mold members of the present invention can be made by a combination of injection molding and machining, lathing or cutting, for example, wherein the basic shape of the mold member is prepared by injection molding and a portion of the mold member is removed, for example, by machining, lathing or cutting a portion of the mold member, thereby preparing all or a portion of the molding surface of optical quality, for example, all or a portion of the mold area for molding the optical zone of the contact lens.

For injection molding of the less polar thermoplastic polymers described herein, in one example, the mold tool used to form the mold member can be maintained at a temperature of about 30 ℃ to about 70 ℃ during the injection molding process. Additionally or optionally, one or more of the following injection molding conditions may be used: melt temperatures of about 245 ℃ and about 270 ℃, hold temperatures of about 235 ℃ to about 270 ℃, feed temperatures of about 235 ℃ to about 250 ℃, hold pressures of about 60 bar to about 125 bar, and ejection velocities of about 50mm/sec to about 125mm/sec through about 3mm orifices.

In one example, the amount of the at least one less polar thermoplastic polymer included in the at least one mold member is effective to produce ophthalmically acceptable wettable ophthalmic lenses, including (but not limited to) ophthalmically acceptable wettable silicone hydrogel contact lenses. The ophthalmically acceptable wettable ophthalmic lenses can also be ophthalmically compatible lenses, such as ophthalmically compatible silicone hydrogel contact lenses.

As used herein, "ophthalmically compatible silicone hydrogel contact lenses" refers to silicone hydrogel contact lenses that can be worn on the eye of a person without the person experiencing or reporting significant discomfort, including ocular irritation, and the like. These lenses often have oxygen permeability, surface wettability, modulus (modulius), water content, ion flux (ionoflurux), design, and combinations thereof that allow the lens to be comfortably worn on a patient's eye for extended periods of time, such as at least one day, at least one week, at least two weeks, or about one month, without removing the lens from the eye. Generally, ophthalmically compatible silicone hydrogel contact lenses do not cause or are not associated with the following: significant corneal edema, corneal dehydration ("dry eye"), superior epithelial arch damage ("SEAL"), or other significant discomfort. Ophthalmically compatible silicone hydrogel contact lenses meet the clinical acceptability requirements for daily or extended wear contact lenses.

Ophthalmically compatible silicone hydrogel contact lenses have ophthalmically acceptably wettable surfaces, although lenses having ophthalmically acceptable wettable surfaces need not be ophthalmically compatible. A silicone hydrogel contact lens having an ophthalmically acceptably wettable surface can be understood to refer to a silicone hydrogel contact lens that does not adversely affect the tear film of the lens wearer's eye to a degree that the lens wearer experiences or reports discomfort associated with placement or wearing of the silicone hydrogel contact lens on the eye.

An ophthalmic lens includes a lens body having surfaces, such as an anterior surface and a posterior surface. As used herein, an ophthalmically acceptably wettable ophthalmic lens is a lens body having surfaces all having ophthalmically acceptable wettability. Wettability refers to the hydrophilicity of one or more surfaces of the lens. As used herein, a lens surface may be considered wettable, or have an ophthalmically acceptable wettability, if the lens has a score of 3 or more than 3 in a wettability analysis performed as follows. Ophthalmic lenses were immersed in distilled water, removed from the water, and the length of time it took for the water film to fall off the lens surface (e.g., water film break time (WBUT)) was determined. The analysis ranks the lenses on a linear scale from 1 to 10, where 10 points to a lens where a droplet takes 20 seconds or more to fall from the lens. Lenses with WBUTs in excess of 5 seconds (e.g., at least 10 seconds or in excess of 10 seconds, desirably at least about 15 seconds) can be ophthalmically acceptably wettable lenses. Wettability can also be determined by measuring the contact angle on one or both lens surfaces. The contact angle may be a dynamic or static contact angle, a sessile drop contact angle, a hanging drop contact angle, or a captive bubble (captivebubble) contact angle. A smaller contact angle generally means a higher wettability of the contact lens surface. For example, an ophthalmically acceptably wettable lens surface can have a contact angle of less than or equal to about 120 degrees. However, in certain examples, the contact angle of the lens is not greater than about 90 degrees, and in other examples, the advancing contact angle of the lens is less than or equal to about 80 degrees.

As described herein, ophthalmic lenses cast molded using less polar thermoplastic polymers have ophthalmically acceptably wettable surfaces when fully hydrated, and do not require the application of a surface treatment or the presence of an interpenetrating network of a polymeric wetting agent in the lens body to provide the lenses with ophthalmically acceptably wettable surfaces. However, applying a surface treatment to the lens or the presence of an interpenetrating network of a polymeric wetting agent in the lens body can be used to further increase the wettability of the lens surface beyond what is considered ophthalmically acceptable wettability.

In contrast, the use of a non-polar or hydrophobic polymer as the sole or primary mold material in a mold member for cast molding ophthalmic lenses, including silicone hydrogel contact lenses, does not impart an ophthalmically acceptably wettable surface to the lens surface of the lens bodies produced thereby. Typically, ophthalmic lenses manufactured using non-polar or hydrophobic mold materials undergo a surface treatment after curing, or include an interpenetrating network (IPN) of a polymeric wetting agent in the lens body, and due to the surface treatment or the presence of the IPN, the lenses become ophthalmically acceptably wettable when fully hydrated. In other words, most silicone hydrogel contact lens bodies cast molded in a non-polar thermoplastic polymer mold and having no surface treatment or IPN that does not include a polymeric wetting agent are not ophthalmically acceptably wettable when fully hydrated.

As used herein, "non-polar polymeric contact lens molds" or "hydrophobic polymeric contact lens molds" refer to contact lens molds formed or manufactured from non-polar or hydrophobic polymers. Thus, non-polar polymer-based contact lens molds can comprise non-polar or hydrophobic polymers. For example, the contact lens molds can comprise one or more polyolefins, or can be formed from polyolefin materials. Examples of non-polar polymeric contact lens molds for use in the context of the present invention include polyethylene contact lens molds, polypropylene contact lens molds, and polystyrene contact lens molds. Contact lens molds based on non-polar polymers typically have hydrophobic surfaces. For example, a non-polar polymer mold or a hydrophobic polymer mold may have a static contact angle of about 90 ° or greater than 90 °, as determined using a captive bubble method. At the contact angle, conventional ophthalmic lenses, including conventional silicone hydrogel contact lenses manufactured with the molds, do not have ophthalmically acceptably wettable surfaces. In addition, the surfaces of these lenses typically do not have ophthalmically acceptably wettable surfaces.

One measure of the ability of a mold member, including mold members comprising less polar thermoplastic polymers, to mold silicone hydrogel contact lenses having ophthalmically acceptably wettable surfaces is the contact angle of the mold member. The contact angle may include a dynamic or static contact angle, a sessile drop contact angle, a hanging drop contact angle, or a captive bubble contact angle. In one example, the contact angle may be measured using a bubble trap method, and may be performed in pure water using a contact angle tester, such as a CA-DT type or a KrussDSA100 instrument (hamburger gmbh, Hamburg) manufactured by kyowa kaimen kagakuco. The measurement can be carried out at 25 ℃.

The process of cast molding silicone hydrogel contact lens bodies typically begins with the preparation of a pair of mold members (i.e., a first mold member and a second mold member). The mold member can be made by injection molding a thermoplastic polymer mold material in a mold cavity, by lathing the polymer mold material to form the entire mold member, or by a combination of injection molding and lathing, such as injection molding to form the basic shape of the mold member, followed by lathing all or a portion of the lens forming area of the mold member.

Typically, two mold members are combined to cast mold a contact lens body. The two mold members are sized and structured to be assembled together, defining a lens-forming cavity therebetween. The two mold members can each include a concave lens-forming surface for molding the anterior surface of the optic or a convex lens-forming surface for molding the posterior surface of the optic. For the purposes of the present invention, a mold part having a concave lens-forming surface is referred to as a first mold part or female mold part, while a mold part having a convex lens-forming surface is referred to as a second mold part or male mold part. The first and second mold members can be structured to form a lens-shaped cavity therebetween when assembled with one another to form a mold assembly. Alternative mold member configurations, such as mold assemblies comprising more than two mold members or mold members having shapes or structures different from those described above, may be used with the low polarity thermoplastic polymer mold materials described herein. In addition, these mold members can be configured to include more than one lens forming area. For example, a single mold member can be configured to include an area configured to mold a lens front surface as well as a lens back surface, i.e., to act as a female or male mold member.

The at least one less polar thermoplastic polymer may be used to form at least one mold part, such as a first mold part or a second mold part, or may be used to form two mold parts, such as a first mold part and a second mold part. The polarity of the first mold part and the polarity of the second mold part may both be about 1% to about 7%. The polarity of the first mold member may be in the range of about 6 percentage points of the polarity of the second mold member (e.g., the polarity of the first mold member may be about 1% and the polarity of the second mold member may be about 7%). Similarly, the polarity of the first mold part may be in a range of about 5 percentage points, about 4 percentage points, about 3 percentage points, about 2 percentage points, or about 1 percentage point of the polarity of the second mold part. Alternatively, the polarity of the first mold member may be about the same as the polarity of the second mold member (e.g., the polarity of both the first mold member and the second mold member may be about 1%, about 2%, about 3%, about 4%, about 5%, about 6%, or about 7%).

As previously discussed, when the mold members configured as mold assemblies to form lens-shaped cavities therebetween are manufactured using the less polar thermoplastic polymer materials described herein, the process of assembling the mold members into a mold assembly can further include the step of forming some connection between the mold members. The first mold member and the second mold member can be structured to be easily separated after assembly together, preferably without substantial damage to at least one of the first and second mold members and the ophthalmic lens product being manufactured in the lens-shaped cavity. In one example, the mold members may be configured to form a mechanical connection based on the shape of the elements in the mold members, such as an interference fit (interference fit) between the mold members, threads between the mold members, bores and protrusions between the mold members, or other locking structures. In another example, a weld may be formed between mold members by melting a region of one or more mold members. In another example, a bonding substance, such as in the form of a glue, contact cement (sealant), or sealant, may be used to form a bond between the mold parts. In another example, additional elements, such as clips, clamps, or brackets, may be used to join the mold parts together. Regardless of the type of connection used between the mold parts, the connection is intended to keep the mold parts aligned during the curing process and needs to be releasable prior to or as part of the demolding process.

During the process of manufacturing the lens body, the polymerizable composition that forms the lens is filled into the mold members prior to combining the individual mold members to form the mold assembly. Typically, this is accomplished by placing a predetermined amount of the polymerizable composition into the concave molding surface of the first mold member. The mold assembly is then assembled by placing the convex molding surface of the second mold member in contact with the first mold member such that a lens-shaped cavity is formed between the first and second mold members, the lens-shaped cavity containing the polymerizable composition. In use, a connection is then made between the first and second mold parts by any available means in order to maintain the mold parts in proper alignment during the curing process. As previously described, the process of forming the connection may include, for example, welding the mold parts together, gluing the mold parts together, applying pressure to the mold parts to engage an interference fit, threading the mold parts together, applying a clamp to the mold parts, and the like.

The mold assembly comprising the polymerizable composition is then cured in the lens-shaped cavity to form a lens body. Curing typically comprises applying a form of electromagnetic radiation to a mold assembly comprising the polymerizable composition so as to polymerize the polymerizable composition in a lens-shaped cavity of the mold assembly. Forms of electromagnetic radiation may include thermal radiation, visible light, Ultraviolet (UV) light, and the like. The mold assembly can be cured using a combination of two or more forms of electromagnetic radiation and two or more levels of one or more forms of electromagnetic radiation. The curing process typically involves curing the mold assembly until the polymerizable composition has polymerized sufficiently that the lens body will retain the shape of the lens-shaped cavity after demolding and delensing. Thus, the curing process may not cause complete reaction of all polymerizable components in the polymerizable composition.

The mold members of the mold assembly can be separated using a "wet" or "dry" demolding method. As previously discussed, wet demolding methods involve applying a liquid to a mold assembly comprising a polymerized lens body. When a wet demolding method is used, ultrasonic energy may optionally be applied to the liquid and mold assembly to assist in the demolding process.

The dry demolding process involves the use of a mechanical process to separate the two mold members of a mold assembly, the assembly comprising a polymeric lens body. In a dry demolding process, the mold assembly comprising the polymerized lens body is not in contact with a liquid, such as an organic solvent, water, or aqueous solution, during the demolding process, and typically, the mold assembly comprising the polymerized lens body is not exposed to the liquid prior to the dry demolding process. After the dry demolding process, the polymerized lens body remains in contact with one and only one of the two mold members used to mold the lens body. In one example, a dry demolding process may include pressing one or more mold members to deform the mold members and separating the two mold members, leaving the polymerized lens body in contact with one of the two mold members. If the mold members of the mold assembly are held together, at least in part, by an interference fit between the two mold members, the dry demolding process can include applying pressure to one or both of the mold members in order to push the mold members away from each other to break the interference fit. Dry demolding may include penetrating the material of the weld if the mold members of the mold assembly are held together, at least in part, by the weld between the two mold members.

After the demolding process, it may be desirable for the lens body to remain in contact with a particular mold member, such as the first or second mold member. To help the lens body remain in contact with the desired mold part, heat may be applied to the first or second mold part, for example, by blowing hot air on the back side of the mold part. Alternatively, the first or second mould part may be cooled, for example by blowing cool air over the back side of the mould part. Applying pressure to the first or second mold member prior to demolding or concurrently with the demolding process may also help the lens body remain in contact with the particular mold member (i.e., the first or second mold member) after the demolding process.

The lens body can be separated from one and only one mold member (i.e., the first or second mold member) that it remains in contact with after the demolding step using a "wet" or "dry" delensing process. As previously discussed, the wet delensing method involves applying a liquid to the polymerized lens body and the one and only one mold member. When using a wet delensing method, ultrasonic energy may optionally be applied to the liquid and the one and only one mold member as part of the delensing process to assist in the release of the lens body from the one and only one mold member. The released lens body can be transferred to a package or tray immediately after wet delensing and inspected, or can optionally be left to stand in a liquid (e.g., de-ionized water) for wet delensing for a period of time, e.g., to partially or fully hydrate the released lens. The temperature of the delensing liquid can also be controlled during the delensing process and optional resting time.

The dry delensing process involves the use of a mechanical process to release the lens body from one of the remaining mold members with which the lens body is in contact after the demolding step. In a dry delensing process, the lens body and a remaining mold part with which the lens body is in contact are not contacted with a liquid, such as water or an aqueous solution, as part of the delensing process. While it is possible to use a wet demolding process (involving application of a liquid to a mold assembly comprising a polymeric lens body) prior to a dry delensing process, it is more common to use a dry demolding process prior to a dry delensing process. When a dry demolding process is used with a dry delensing process, the lens body is not exposed to a liquid, such as an organic solvent, water, or aqueous solution, until the lens body has been released from both mold members of the mold assembly (i.e., from the first and second mold members). In one example, a dry delensing process may involve the use of vacuum equipment to lift the polymerized lens body from one of the remaining mold members with which it is in contact after the demolding step. The dry delensing process may also involve pressing the one remaining mold member to at least partially break the bond between the one mold member. The dry delensing process can involve inserting a pry tool between the edge of the lens body and the mold member to at least partially break the bond between the lens body and the mold member.

When a dry demolding process, a dry delensing process, or both a dry demolding process and a dry delensing process are used, the thermoplastic polymer used to form at least the molding surface of at least one mold member in the mold assembly can comprise polybutylene terephthalate (PBT), including a mixture of PBT and an additive, such as a form of a fatty acid. The form of the fatty acid may include free fatty acids, fatty acid esters, metal salts of fatty acids, and combinations thereof.

Silicone hydrogel lens bodies cast molded using a less polar thermoplastic polymer mold may not require the use of one or more organic solvent-based washing steps to provide the resulting lens body with ophthalmically acceptable wettability, although organic solvent-based washing steps may be used to increase wettability or for other purposes. For example, these silicone hydrogel lens bodies have ophthalmically acceptable wettability after washing in aqueous solutions (including aqueous solutions substantially free of organic solvents such as volatile alcohols). Examples of volatile alcohols include methanol, ethanol, propanol, and the like. Aqueous solutions substantially free of organic solvents for washing lenses of the invention may include saline solutions, buffer solutions, surfactant solutions, wetting agent solutions, conditioner (comfortagent) solutions, combinations thereof, and the like. In one example, the lenses of the invention can be washed with one or more polymeric wetting agents or care agents. However, it should be understood that the lenses of the invention have ophthalmically acceptably wettable surfaces when washed in aqueous solutions that do not contain any polymeric wetting or conditioning agents. Thus, while polymeric wetting agents or conditioning agents may be used to increase the wettability of the lenses of the invention, their wettability is not solely dependent upon the use of these agents.

Although the use of an organic solvent-based washing step is not necessary to provide an ophthalmically acceptable wettability for the lenses described herein, one or more of the steps described herein may be used with the lenses of the invention, for example to clean the lens body by removing dust or debris; extracting the lens body by removing unreacted or partially reacted monomers, macromers or prepolymers, or other materials; or partially hydrating the lens (when an aqueous organic solvent solution is used). In addition, the lens bodies of the present invention can be subjected to one or more organic solvent-based washing steps in order to increase the wettability of the lens body to a level that exceeds the ophthalmically acceptable wettability levels achievable based on molding the lens body using less polar mold materials.

As used herein, the term "hydrogel" refers to a polymeric material, typically a network or matrix of polymer chains, that is capable of swelling in water or becoming swollen in the presence of water. A hydrogel is also understood to be a material that keeps water in an equilibrium state. The network or matrix may or may not be crosslinked. Hydrogels refer to water-swellable or water-swollen polymeric materials, including contact lenses. Thus, the hydrogel may be (i) unhydrated and water-swellable; or (ii) partially hydrated and water-swollen; or (iii) fully hydrated and water swollen. The hydrogel may be a silicone hydrogel, a silicone-free hydrogel, or a substantially silicone-free hydrogel.

The term "silicone hydrogel" or "silicone hydrogel material" refers to a particular hydrogel that includes a silicon (Si) -containing component or a Silicone (SiO) -containing component. For example, silicone hydrogels are typically prepared by combining a silicon-containing material with a conventional hydrophilic hydrogel precursor. Silicone hydrogel contact lenses are contact lenses, including vision correcting contact lenses, comprising a silicone hydrogel material.

A "silicone-containing" component is a component that contains at least one [ -Si-O-Si- ] linkage. The silicone-containing component can be a monomer, macromer or prepolymer. In one example, one or more silicon atoms in the silicone-containing component can optionally have one or more organyl group substituents (R1, R2) or substituted organyl group substituents in some manner, e.g., can optionally be chemically (e.g., covalently) bonded to one or more organyl group substituents (R1, R2) or substituted organyl group substituents. The organic group substituents or substituted organic group substituents may be the same or different, for example-SiR 1R 2O-.

In the context of the polymers described herein, "molecular mass" refers to the nominal average molecular mass of the polymer as determined by size exclusion chromatography, light scattering techniques, or intrinsic viscometry in 1,2, 4-trichlorobenzene. In the case of polymers, molecular weight may be expressed as a number average molecular weight or a weight average molecular weight, and in the case of vendor supplied materials will depend on the supplier. Typically, if the basis for any such molecular weight determination is not provided in the packaging material, it can be readily provided by the supplier. Generally, reference herein to the molecular weight of a monomer, macromer, prepolymer, or polymer herein refers to weight average molecular weight. The determination of both molecular weights (both number average and weight average) can be measured using gel permeation chromatography or other liquid chromatography techniques. Other methods of measuring molecular weight values may also be used, such as determining number average molecular weight using end group analysis or measuring colligative properties (e.g., freezing point depression, boiling point elevation, or osmotic pressure), or determining weight average molecular weight using light scattering techniques, ultracentrifugation, or viscometry.

The "network" or "matrix" of hydrophilic polymers generally means that crosslinks are formed between polymer chains by covalent bonds or by physical bonds such as hydrogen bonds. The network can include two or more polymer components and can include an interpenetrating network (IPN) in which one polymer is physically entangled with a second polymer such that a small number, if any, of covalent bonds are present therebetween, but the polymers cannot be separated from one another without disrupting the network.

"hydrophilic" substances are substances that are water-loving or have an affinity for water. Hydrophilic compounds have an affinity for water and are often charged or have polar moieties or groups that attract water.

As used herein, "hydrophilic polymer" is defined as a polymer that has an affinity for water and is capable of absorbing water. The hydrophilic polymer need not be soluble in water. The hydrophilic polymer is soluble in water, or insoluble (e.g., substantially insoluble) in water.

A "hydrophilic component" is a hydrophilic substance that may or may not be a polymer. Hydrophilic components include components that are capable of providing a water content of at least about 20% (w/w), such as at least about 25% (w/w), when combined with the remaining reactive components. The hydrophilic component may include a hydrophilic monomer, a hydrophilic macromer, a hydrophilic prepolymer, a hydrophilic polymer, or a combination thereof. Hydrophilic macromers, hydrophilic prepolymers and hydrophilic polymers are also understood to have hydrophilic and hydrophobic portions. Typically, the hydrophilic and hydrophobic portions are present in relative amounts such that the macromer, prepolymer, or polymer is hydrophilic.

"monomer" refers to a relatively low molecular weight compound, such as a polymerizable compound having an average molecular weight of less than or equal to 700 daltons (Dalton). In one example, a monomer may comprise a single molecular unit containing one or more functional groups capable of polymerizing to form a polymer in combination with other molecules having the same structure or a different structure than the monomer.

"macromer" refers to medium and high molecular weight compounds or polymers, which may contain one or more functional groups capable of polymerization or further polymerization. For example, the macromer may be a compound or polymer having an average molecular weight of about 700 daltons to about 2,000 daltons.

"prepolymer" refers to a polymerizable or crosslinkable compound of relatively high molecular weight. As used herein, a prepolymer may contain one or more functional groups. In one example, the prepolymer may be a series of monomers or macromers that are bonded together such that the entire molecule remains polymerizable or crosslinkable. For example, the prepolymer can be a compound having an average molecular weight of greater than or equal to about 2,000 daltons.

"Polymer" means a material formed by the polymerization of one or more monomers, macromers, prepolymers, or mixtures thereof. As used herein, a polymer is understood to mean a molecule that is not capable of polymerizing, but is capable of crosslinking with other polymers (e.g., other polymers present in the polymerizable composition or other polymers formed in the polymerizable composition during reaction of the monomers, macromers, and/or prepolymers).

"interpenetrating network" or "IPN" refers to a combination of two or more different polymers in the form of a network, at least one of which is synthesized (e.g., polymerized) and/or crosslinked in the presence of the other and which does not contain or substantially does not contain any covalent bonds between the two. IPNs may be composed of two types of chains that form two separate but juxtaposed or interpenetrating networks. Examples of IPNs include sequential IPNs, synchronous IPNs, semi-IPNs, and homogeneous IPNs (homo-IPNs).

"pseudo ipn (pseudoipn)" refers to a polymerization reaction product in which at least one of the different polymers is crosslinked and at least one other polymer is non-crosslinked (e.g., linear or branched), wherein the non-crosslinked polymer is molecularly distributed in and held by the crosslinked polymer such that the non-crosslinked polymer is substantially not extractable from the network.

By "polymer mixture" is meant a polymeric reaction product in which the different polymers are linear or branched and are not substantially crosslinked, wherein the resulting polymer blend is a mixture of polymers at the molecular level.

"graft polymer" refers to a branched polymer having side chains comprising a homopolymer or copolymer different from the backbone.

Unless otherwise specified, "attached" may refer to any of charge attachment, grafting, complexing, bonding (chemical or hydrogen bonding), or adhesion.

As used herein, "ophthalmically acceptable lens-forming components" refers to lens-forming components that can be incorporated into hydrogel contact lenses without significant discomfort (including ocular irritation, etc.) experienced or reported by the lens wearer. Ophthalmically acceptable hydrogel contact lenses have ophthalmically acceptable surface wettability and typically do not cause or are not associated with: significant corneal edema, corneal dehydration ("dry eye"), superior epithelial arch damage ("SEAL"), or other significant discomfort.

The term "organic solvent" refers to organic species present in the body of a contact lens that have not previously undergone extraction processing that are capable of solvating or dissolving at least one material, such as, but not limited to, unreacted species, diluents, and the like. In one example, the substance is one that is insoluble or does not dissolve in water or an aqueous solution. In another example, the substance is one that is not or not substantially soluble in water or an aqueous solution, i.e., the substance has increased solvation in an organic solvent as compared to water or an aqueous solution. Thus, the organic solvent contacting the unextracted contact lens body is effective to solvate or dissolve at least one substance present in the lens body, or to increase the solvation or to dissolve to a greater extent at least one substance present in the lens body to reduce the concentration of said at least one substance present in the lens body, or to reduce the concentration of said at least one substance in the lens body as compared to a lens body treated with water or an aqueous solution. The organic solvent may be used undiluted, i.e., 100% organic solvent, or may be used in the form of a composition comprising less than 100% organic solvent, such as, but not limited to, an aqueous solution comprising organic solvent. Generally, the organic solvent acts on (e.g., directly acts on) the at least one substance to solvate or dissolve the at least one substance. Examples of organic solvents include, but are not limited to, alcohols (e.g., alkyl alcohols such as ethanol, isopropanol, and the like), chloroform, butyl acetate, tripropylene glycol methyl ether, dipropylene glycol methyl ether acetate, and the like, and mixtures thereof.

The term "surfactant" or "surfactant component" refers to a substance that is capable of reducing the surface tension of water (e.g., water or an aqueous solution in which the substance is present). The surfactant or surfactant component facilitates the water containing the surfactant or surfactant component to more intimately contact the lens body and/or more effectively wash or remove at least one substance present in the lens body from the lens body when contacting a contact lens body that has not previously been subjected to extraction processing with an organic solvent by reducing the surface tension of the water relative to water without the surfactant or surfactant component. Generally, the surfactant or surfactant component does not act directly on the at least one substance to solvate or dissolve the at least one substance. Examples of surfactants or surfactant components include, but are not limited to, zwitterionic surfactants, including betaine forms; nonionic surfactants, including polysorbate forms (e.g., polysorbate 80), poloxamer (poloxamer) or poloxamine (poloxamine) forms; fluorinated surfactants, and the like; and mixtures thereof. In one example, one or more surfactants can be incorporated into the polymerizable compositions described herein, the wash solutions described herein, the packaging solutions described herein, and combinations thereof.

Other definitions can also be found in the following section.

Lens formulation hydrogels represent a class of materials for use in the present contact lenses. Hydrogels comprise hydrated, crosslinked polymer systems containing water in an equilibrium state. Thus, a hydrogel is a copolymer prepared from one or more reactive ingredients. These reactive ingredients may be crosslinked with a crosslinking agent.

Hydrophilic monomers the hydrophilic monomers can be, for example, silicone-containing monomers having hydrophilic moieties, non-silicone containing hydrophilic monomers, or combinations thereof. Hydrophilic monomers may be used in combination with hydrophobic monomers. The hydrophilic monomer may be a monomer having hydrophilic and hydrophobic moieties (moieties or moieties). The type and amount of hydrophilic monomer used in the polymerizable lens composition can vary depending on the type of other lens-forming monomers used. Non-limiting illustrations regarding hydrophilic monomers for use in silicone hydrogels are provided herein.

Crosslinking agents the crosslinking agents of the monomers, macromers or prepolymers used to prepare the hydrogels may include crosslinking agents known in the art, and examples of crosslinking agents are also provided herein. Suitable crosslinkers include, for example, diacrylate (or divinyl ether) functionalized ethylene oxide oligomers or monomers such as tri (ethylene glycol) dimethacrylate (TEGDMA), tri (ethylene glycol) divinyl ether (TEGDVE), Ethylene Glycol Dimethacrylate (EGDMA), and propylene glycol dimethacrylate (TMGDMA). Typically, the crosslinking agent is present in the polymerizable silicone hydrogel composition in a relatively minor total amount of the polymerizable composition, for example, in an amount in the range of from about 0.1% (w/w) to about 10% (w/w), or from about 0.5% (w/w) to about 5% (w/w), or from about 0.75% (w/w) to about 1.5% (w/w), based on the weight of the polymerizable composition.

In one example, one or more monomers, macromers or prepolymers may comprise crosslinking functionality. In these cases, a crosslinking agent is optionally additionally used in addition to the monomer, macromer or prepolymer having crosslinking functional groups, and the monomer, macromer or prepolymer having crosslinking functional groups may be present in the polymerizable silicone hydrogel composition in a relatively large amount, for example, at least about 3% (w/w), at least about 5% (w/w), at least about 10% (w/w), or at least about 20% (w/w).

Silicone hydrogel polymerizable lens-forming compositions the silicone hydrogel polymerizable lens-forming compositions can comprise at least one silicone-containing component and at least one compatible hydrophilic monomer. In one example, the polymerizable composition can further comprise at least one compatible crosslinking agent. In another example, the silicone-containing component can serve as both a crosslinker and a silicone-containing component. For the polymerizable compositions discussed herein, a "compatible" component refers to a component that, when present in the polymerizable composition prior to polymerization, forms a single phase that remains stable for a duration sufficient to allow a polymerized lens body to be made from the composition. For some components, various concentrations may be found to be compatible. In addition, a "compatible" component is a component that when polymerized to form a polymerized lens body results in a lens having physical characteristics (e.g., sufficient clarity, modulus, tensile strength, etc.) sufficient for use as a contact lens.

The Si and attached O moieties (Si-O moieties) in the silicone-containing component can be present in the silicone-containing component in an amount greater than or equal to 20% (w/w), for example greater than or equal to 30% (w/w), of the total molecular weight of the silicone-containing component. Useful silicone-containing components contain polymerizable functional groups such as vinyl, acrylate, methacrylate, acrylamide, methacrylamide, N-vinyl lactam, N-vinyl amide, and styryl functional groups. The silicone-containing component that can be polymerized, for example, to obtain the contact lenses of the invention comprises one or more silicone-containing monomers, one or more silicone-containing macromers, one or more silicone-containing prepolymers, or mixtures thereof. Silicone hydrogel contact lenses made as described herein can be based on silicone-containing monomers and/or silicone-based macromers and/or silicone-based prepolymers, as well as hydrophilic monomers or comonomers, and crosslinking agents. Examples of other silicone-containing components that can be used in the lenses of the invention, in addition to the other silicone-containing compounds described herein, can be found in U.S. Pat. Nos. 3,808,178, 4,120,570, 4,136,250, 4,139,513, 4,153,641, 4,740,533, 5,034,461, 5,496,871, 5,959,117, 5,998,498 and 5,981,675, and U.S. patent application publications 2007/0066706A1, 2007/0296914A1 and 2008/0048350A1, each of which is incorporated herein by reference in its entirety. The silicone-containing component can be a silicone-containing monomer or a silicone-containing macromer or a silicone-containing prepolymer.

The silicone-containing monomer, macromer or prepolymer can have, for example, the following general formula (I):

wherein R is⁵Is H or CH₃X is O or NR⁵⁵Wherein R is⁵⁵Is H or a monovalent alkyl group having from 1 to 4 carbon atoms, a is 0 or 1, L is a divalent linking group (e.g., a polyethylene glycol chain) containing from 1 to 20 carbon atoms or from 2 to 10 carbon atoms and may also optionally contain ether and/or hydroxyl groups, p may be from 1 to 10 or from 2 to 5, R₁R₂And R₃May be the same or different and are independently selected from the group consisting of hydrocarbyl groups having from 1 to about 12 carbon atoms (e.g., methyl groups), hydrocarbyl groups substituted with one or more fluorine atoms, siloxane groups, and groups containing siloxane chain moieties, wherein R is₁、R₂And R₃At least one of which comprises at least one siloxane unit (-OSi). For example, R₁、R₂And R₃At least one of which may comprise-OSi (CH)₃)₃and/or-OSi (R)⁵²R⁵³R⁵⁴) Wherein R is⁵²、R⁵³R⁵⁴Independently ethyl, methyl, benzyl, phenyl, or a monovalent siloxane chain comprising from 1 to about 100, or from about 1 to about 50, or from about 1 to about 20 Si-O repeat units.

R₁、R₂And R₃One, two or all three may also comprise other siloxane groups or siloxane chain-containing moieties. The combined linkage-X-L-when present in the silicone-containing monomer, macromer or prepolymer of structure (I), may contain one or more heteroatoms, which are O or N. The combined linkage may be a straight chain or a branched chain, wherein the carbon chain segments thereof may be straight. The combined linkage-X-L-may optionally contain one or more functional groups selected from, for example, carboxyl, amide, carbamate, and carbonate. Examples of such combination linkages are provided, for example, in U.S. patent No. 5,998,498 and U.S. patent application publication nos. 2007/0066706a1, 2007/0296914a1 and 2008/0048350, the entire disclosures of each of which are incorporated herein by reference. The silicone-containing monomer, macromer or prepolymer used according to the present invention may comprise a single unsaturated or acryloyl group, such as shown in structure (I), or it may optionally have two unsaturated or acryloyl groups, such as one at each end of the monomer, macromer or prepolymer. Combinations of two types of silicone-containing monomers, macromers or prepolymers optionally can be used in the polymerizable compositions that can be used in accordance with the present invention.

Examples of silicone-containing components that can be used in accordance with the present invention include, for example, but are not limited to, polysiloxanylalkyl (meth) acrylic monomers, macromers, or prepolymers, including, but not limited to, methacryloxypropyltris (trimethylsiloxy) silane, pentamethyldisiloxanylmethacrylate, and methyldi (trimethylsiloxy) methacryloxymethylsilane.

Specific examples of useful silicone-containing monomers, macromers or prepolymers can be, for example, 3- [ tris (trimethylsiloxy) silyl methacrylate]Propyl ("Tris", available from Gelest, Morrisville, Pa., USA), and monomethacryloxypropyl terminated polydimethylsiloxane ("MCS-M11", available from Gelest, Morrisville, Pa., USA). Examples of some silicone-containing monomers are disclosed in U.S. patentApplication publication No. 2008/0269429. These silicone-containing monomers can have an alkylene group as a divalent linking group (e.g., - (CH)₂)_p-) and "a" can be 0 for structure (I) and have at least two siloxane groups. These silicone-containing components are designated herein as silicone-containing monomers of structure (a). Exemplary, non-limiting structures of these silicone-containing monomers are shown below:

other specific examples of silicone-containing components that may be used in the present invention may be, for example, 3-methacryloxy-2-hydroxypropoxy) propylbis (trimethylsiloxy) methylsilane ("SiGMA", available from Girarast, Morisville, Pa., U.S.) and methyldi (trimethylsiloxy) silylpropylglycerol ethyl methacrylate ("SiGEMA"). These silicone-containing components include at least one hydroxyl group and at least one ether group in the divalent linking group L shown in structure (I), and at least two siloxane groups. These silicone-containing components are designated herein as silicone-containing components of the structure (B) class. Additional details regarding such silicone-containing components are provided, for example, in U.S. patent No. 4,139,513, which is incorporated herein by reference in its entirety. For example, SiGMA may be represented by the following exemplary, non-limiting structure:

the silicone-containing components of structures (a) and (B) may be used independently or in any combination thereof in the polymerizable compositions that may be used in accordance with the present invention. The silicone-containing component of structures (a) and/or (B) may be further used in combination with at least one non-silicone-containing hydrophilic monomer (e.g., as described herein). For example, if used in combination, the amount of the silicone-containing component of structure (A) can be, for example, from about 10% (w/w) to about 40% (w/w), or from about 15% (w/w) to about 35% (w/w), or from about 18% (w/w) to about 30% (w/w). The amount of the silicone-containing component of structure (B) can be, for example, from about 10% (w/w) to about 45% (w/w), or from about 15% (w/w) to about 40% (w/w), or from about 20% (w/w) to about 35% (w/w).

Other specific examples of useful silicone-containing components that can be used in accordance with the present invention can be chemicals represented by the following formula, or chemicals described in Japanese patent application publication No. 2008-202060A (incorporated herein by reference in its entirety), for example

Other specific examples of useful silicone-containing components that can be used in accordance with the present invention can be chemicals represented by the following formula, or chemicals described in U.S. patent application publication No. 2009/0234089 (incorporated herein by reference in its entirety). In one example, the silicone-containing component can comprise one or more hydrophilic polysiloxane components represented by the general formula (II),

wherein R is₁Selected from hydrogen or methyl; r₂Selected from hydrogen or C_1-4A hydrocarbyl group; m represents an integer of 0 to 10; n represents an integer of 4 to 100; a and b represent 1 or an integer of 1 or more; a + b equals 20 to 500; b/(a + b) equals 0.01 to 0.22; and the configuration of the siloxane units comprises a random configuration. Examples of such silicone-containing components are described in the examples section of U.S. patent application publication No. 2009/0234089, including example 2 on page 7.

Other silicone-containing components may also be used. For example, other suitable types may include, for example, poly (organosiloxane) monomers, macromers, or prepolymers, such as α, ω -bis-methacryloxy-propylpolydimethylsiloxane. Another example is mPDMS (monomethacryloxypropyl terminated mono n-butyl terminated polydimethylsiloxane). Other useful silicone-containing components include silicone-containing vinyl carbonate or vinyl carbamate monomers, macromonomers or prepolymers, including, but not limited to, 1, 3-bis [4- (vinyloxycarbonyloxy) but-1-yl ] tetramethylsiloxane 3- (vinyloxycarbonylthio) propyl- [ tris (trimethylsiloxysilane ], 3- [ tris (trimethylsiloxy) silyl ] propyl allyl carbamate, 3- [ tris (trimethylsiloxy) silyl ] propyl vinyl carbamate, trimethylsilylethyl vinyl carbonate, and trimethylsilylmethyl vinyl carbonate, examples of one or more of these silicone-containing components are provided, for example, in U.S. Pat. No. 5,998,498 and U.S. patent application publication No. 2007/0066706A1, U.S. Pat. No. 3,985,, 2007/0296914A1 and 2008/0048350, the entire disclosure of each is incorporated herein by reference.

Some of the silicone-containing monomers, macromers or prepolymers that can be used in accordance with the present invention can be used as a single discrete monomer, macromer or prepolymer or can be used as a mixture of two or more discrete monomers, macromers or prepolymers. For example, MCR-M07 is often provided as a mixture of silicone-containing compounds having widely distributed molecular weights. Alternatively, some silicone-containing monomers, macromers or prepolymers which may be used in accordance with the present invention may be provided in the form of two or more monomers, macromers or prepolymers having discrete molecular weights. For example, X-22-1625 may be used in the lower molecular weight form, having a molecular weight of about 9000 daltons, and in the higher molecular weight form, having a molecular weight of about 18,000 daltons.

The polymerizable composition for use as described herein can include one or more hydrophobic monomers, including hydrophobic monomers that are silicone-free. Examples of the non-silicone-containing hydrophobic monomer include, but are not limited to, acrylic acid and methacrylic acid and derivatives thereof, including methyl methacrylate, and combinations of two or more hydrophobic monomers may be employed.

Hydrophilic monomers the polymerizable compositions used to make the silicone hydrogels of the present invention include hydrophilic monomers, including non-silicone containing hydrophilic monomers. The non-silicone-containing hydrophilic monomer does not include hydrophilic compounds containing one or more silicon atoms. Hydrophilic monomers may be used in the polymerizable composition in combination with the silicone-containing monomers, macromers, or prepolymers to form the silicone hydrogel. In silicone hydrogels, hydrophilic monomer components include components that are capable of providing at least about 10% (w/w), or even at least about 25% (w/w), water content when combined with other polymerizable composition components. For silicone hydrogels, the total hydrophilic monomer may comprise from about 25% (w/w) to about 75% (w/w), or from about 35% (w/w) to about 65% (w/w), or from about 40% (w/w) to about 60% (w/w) of the polymerizable composition.

Monomers that can be included as hydrophilic monomers typically have at least one polymerizable double bond, at least one hydrophilic functional group, or both. Examples of polymerizable double bonds include, for example, vinyl, acrylic, methacrylic, acrylamido, methacrylamido, fumaric, maleic, styryl, isopropenylphenyl, O-vinyl carbonate, O-vinyl carbamate, allyl, O-vinylacetyl, and N-vinyllactam and N-vinylamido double bonds. In one example, the hydrophilic monomer is a vinyl-containing monomer (e.g., an acrylic-containing monomer or a vinyl-containing monomer without acrylic acid). These hydrophilic monomers may themselves be used as crosslinking agents.

The hydrophilic monomer may be, but is not necessarily, a cross-linking agent. Considered as a subset of the above acryloyl moieties, "acrylic" or "acrylic-containing" or acrylate-containing monomers are monomers containing an acrylic group (CR' H ═ CRCOX), where R is H or CH₃R' is H, alkyl or carbonyl, and X is O or N, which are also known to polymerize readily.

For silicone hydrogels, hydrophilic groupThe component (a) may comprise a silicon-free hydrophilic monomer component comprising an acrylic monomer (e.g., a monomer having a vinyl group at the α -carbon position and having a carboxylic acid terminal, a monomer having a vinyl group at the α -carbon position and having an amide terminal, etc.) and a vinyl group-Containing (CH)₂A hydrophilic monomer (i.e., a monomer containing a vinyl group that is not part of an acrylic group) of CH —.

Illustrative acrylic monomers include N, N-Dimethylacrylamide (DMA), 2-hydroxyethyl acrylate, glycerol methacrylate, 2-hydroxyethyl methacrylate (HEMA), methacrylic acid, acrylic acid, Methyl Methacrylate (MMA), ethylene glycol methyl ether methacrylate (EGMA), and any mixtures thereof. In one example, the total acrylic monomer content is present in an amount in the range of about 5% (w/w) to about 50% (w/w) of the polymerizable composition used to prepare the silicone hydrogel lens product, and may be present in an amount in the range of about 10% (w/w) to about 40% (w/w), or about 15% (w/w) to about 30% (w/w) of the polymerizable composition.

As described above, the hydrophilic monomer may also comprise a vinyl-containing hydrophilic monomer. Vinyl-containing hydrophilic monomers that can be incorporated into the lens materials of the present invention include, but are not limited to, the following: n-vinyl lactams (e.g., N-vinyl pyrrolidone (NVP)), N-vinyl-N-methyl acetamide (VMA), N-vinyl-N-ethyl acetamide, N-vinyl-N-ethyl formamide, N-vinyl formamide, N-2-hydroxyethyl vinyl carbamate, N-carboxy-beta-alanine N-vinyl ester, and the like, and mixtures thereof. An example of a vinyl-containing monomer is N-vinyl-N-methylacetamide (VMA). The structure of VMA corresponds to CH₃C(O)N(CH₃)-CH＝CH₂. In one example, the total vinyl-containing monomer content of the polymerizable composition is present in an amount ranging from about 0% (w/w) to about 50% (w/w), e.g., up to about 50% (w/v), of the polymerizable composition used to prepare the silicone hydrogel lens product, and can be present in an amount ranging from about 20% (w/w) to about 45% (w/w), or about 28% (w/w) to about 40% (w/w), of the polymerizable composition. Other silicone-free lens-forming hydrophilic monomers known in the art may also be usedAre suitable.

Other examples are hydrophilic vinyl carbonate or vinyl carbamate monomers as disclosed in U.S. Pat. No. 5,070,215, and hydrophilic oxazolone monomers as disclosed in U.S. Pat. No. 4,190,277. Other suitable hydrophilic monomers will be apparent to those skilled in the art. More preferably, hydrophilic monomers that can be incorporated into the polymers of the present invention include hydrophilic monomers such as N, N-Dimethylacrylamide (DMA), 2-hydroxyethyl acrylate, glycerol methacrylate, 2-hydroxyethyl methacrylamide, N-vinyl pyrrolidone (NVP), and polyethylene glycol monomethacrylate. In certain examples, hydrophilic monomers including DMA, NVP, and mixtures thereof are employed.

Other examples of materials used to make silicone hydrogel contact lenses include those disclosed in U.S. patent No. 6,867,245.

Crosslinking agents that may be used in the manufacture of the present contact lenses, such as the present silicone hydrogel contact lenses, include, but are not limited to, the crosslinking agents described above. Examples of acrylate functionalized ethylene oxide oligomers that may be used in the crosslinking agent may include oligomeric ethylene oxide dimethacrylates. The crosslinker can be TEGDMA, TEGDVE, EGDMA, TMGDMA, or any combination thereof. Typically, the crosslinking agent is present in the polymerizable silicone hydrogel composition in a relatively minor total amount of the polymerizable composition, for example, in an amount in the range of from about 0.1% (w/w) to about 10% (w/w), or from about 0.5% (w/w) to about 5% (w/w), or from about 0.75% (w/w) to about 1.5% (w/w), based on the weight of the polymerizable composition.

In one example of a polymerizable composition, the composition comprises a first monomer having a first reactivity ratio, and a second monomer having a second reactivity ratio that is less than the first reactivity ratio. It will be appreciated by those skilled in the art that reactivity ratio can be defined as the ratio of the reaction rate constant for each propagating species adding its own monomer to the rate constant for its addition of other monomers. The composition may also include at least one crosslinker having a reactivity ratio similar to the first reactivity ratio or the second ratio. The composition may also include at least two crosslinking agents, a first crosslinking agent having a reactivity ratio similar to the first reactivity ratio and a second crosslinking agent having a reactivity ratio similar to the second reactivity ratio. In certain examples, the lens precursor composition can include one or more removable additives. For example, the polymerizable composition may include one or more compatibilizing agents, release aids, delensing aids, wettability enhancers, and ion flux reducing agents (ionoflurandreducts), which are removable.

By providing relatively slower reacting monomers in the polymerizable composition, for example by providing two or more monomer types with different reactivity ratios in the same polymerizable composition, the rate at which hydrophilic and hydrophobic (e.g., silicone) monomers react during the curing process, and thus the wettability of the resulting polymerized lens body, can be controlled. In one example, the slower reacting monomer or crosslinker may comprise a vinyl monomer or crosslinker (in other words, a monomer or crosslinker containing vinyl functionality), and the faster reacting monomer or crosslinker may comprise a methacrylate monomer or crosslinker (in other words, a monomer or crosslinker containing methacrylate functionality).

The use of a slower reacting hydrophilic monomer (as opposed to a faster reacting hydrophobic monomer) allows residual unreacted hydrophilic monomer and partially reacted monomers (including uncrosslinked or partially crosslinked hydrophilic polymer chains) to remain in the lens body after the curing process is complete. The presence of these unreacted and partially reacted hydrophilic monomers (e.g., monomers in the polymerizable composition that do not fully crosslink into a network during the curing process) can provide wettability to the polymerized lens body. Agents that do not fully crosslink, such as unreacted or only partially reacted monomers, oligomers, linear polymers, slightly crosslinked components, and the like, may be extracted from the polymerized components of the polymerized silicone hydrogel contact lens product or may remain in the polymerized lens body after washing.

Other hydrogel components the polymerizable composition used in the lenses and in the methods described herein may also include other components, such as one or more initiators (e.g., one or more thermal initiators, one or more Ultraviolet (UV) initiators, visible light initiators, combinations thereof, and the like), one or more UV absorbers or compounds, or UV radiation or energy absorbers, colorants, pigments, mold release agents, antimicrobial compounds, and/or other additives. In the context of the present invention, the term "additive" refers to a compound or any chemical agent provided in the hydrogel contact lens polymerizable composition or polymerized hydrogel contact lens product of the present invention but not necessary for the manufacture of a hydrogel contact lens.

The polymerizable composition may comprise one or more initiator compounds, i.e., compounds capable of initiating polymerization of the polymerizable composition. Thermal initiators, i.e., initiators having a "kick-off" temperature, may be used. For example, exemplary thermal initiators useful in the polymerizable compositions of the present invention include 2, 2' -azobis (isobutyronitrile) (AIBN, VAZO)-64), 2' -azobis (2, 4-dimethylvaleronitrile) (VAZO-52), 2' -azobis (2-methylbutyronitrile) (VAZO)-67) and 1, 1' -azobis (cyclohexanecarbonitrile) (VAZO)-88). For VAZOThermal initiators, the rating numbers (i.e., 64, 52, 67, 88, etc.) are the temperatures in degrees celsius when the half-life of the initiator in solution is 10 hours. All VAZOs described hereinThermal initiators are all available from DuPont (DuPont) (Wilmington, del, USA). Other thermal initiators (including nitrite) and other types of initiators are available from sigma aldrich. Ophthalmically compatible silicone hydrogel contact lenses can be obtained from polymerizable compositions comprising about 0.05% (w/w) to about 0.8% (w/w), or about 0.1% (w/w) to about 0.6% (w/w) VAZO-64 or other thermal initiators.

The UV absorber can be, for example, a strong UV absorber that exhibits relatively high absorbance values in the UV-a range of about 320 to 380 nanometers, but is relatively transparent above about 380 nm. Examples include photopolymerizable hydroxybenzophenones and photopolymerizable benzotriazoles such as 2-hydroxy-4-acryloxyethoxybenzophenone (available as CYASORBUV416 from Cytec industries, West Paterson, NJ, USA, West Pasteur, N.J.), 2-hydroxy-4- (2-hydroxy-3-methacryloyloxy) propoxybenzophenone, and NORBLOC @7966 photopolymerizable benzotriazoles are available from Nolam corporation (Noramco) of Athens, Georgia, USA. Other photopolymerizable UV absorbers suitable for use in accordance with the present invention include polymerizable ethylenically unsaturated triazines, salicylates, aryl-substituted acrylates, and mixtures thereof. Generally, the UV absorber (if present) is provided in an amount corresponding to about 0.5% by weight of the polymerizable composition to about 1.5% by weight of the composition. For example, the composition may include from about 0.6% (w/w) to about 1.0% (w/w) of one or more UV absorbers.

Polymerizable compositions useful according to the present invention can also include colorants, but encompass tinted and clear lens products. In one example, the colorant is a reactive dye or pigment effective to provide color to the resulting lens product. Colorants can include, for example, VAT blue 6(7, 16-dichloro-6, 15-dihydrodianthrapyridazine-5, 9, 14, 18-tetrone), 1-amino-4- [3- (. beta. -sulfatoethylsulfonyl) anilino ] -2-anthraquinone sulfonic acid (c.i. reactive blue (ReactiveBlue)19, RB-19), copolymers of reactive blue 19 with hydroxyethyl methacrylate (RB-19HEMA)1, 4-bis [4- [ (2-methacryloyl-oxyethyl) phenylamino ] anthraquinone (reactive blue 246, RB-246, available from arran chemical company of alaskan (Athlone, Ireland)), 1, 4-bis [ (2-hydroxyethyl) amino ] -9, 10-anthracenedione bis (2-acrylate) ester (RB-247), and mixtures thereof, Reactive blue 4(RB-4) or a copolymer of reactive blue 4 with hydroxyethyl methacrylate (RB-4HEMA or "BlueHEMA"). Other exemplary colorants are disclosed, for example, in U.S. patent application publication No. 2008/0048350, the disclosure of which is incorporated herein by reference in its entirety. Other colorants suitable for use in accordance with the present invention are phthalocyanine pigments (e.g., phthalocyanine blue and phthalocyanine green), chromium-alumina-cobaltous oxide, chromium oxide, and various iron oxides of the red, yellow, brown, and black colors. Opacifiers (opaquinagent) such as titanium dioxide may also be incorporated. For some applications, mixtures of colors may be employed. If employed, the colorant can be present in an amount ranging from about 0.1% (w/w) to about 15% (w/w), or from about 1% (w/w) to about 10% (w/w), or from about 4% (w/w) to about 8% (w/w).

The polymerizable composition may also comprise a release aid, that is, one or more ingredients effective to make the cured contact lens more easily removable from its mold. Exemplary release aids include hydrophilic silicones, polyalkylene oxides, and combinations thereof. The polymerizable composition may further comprise a diluent selected from the group consisting of: hexanol, ethoxyethanol, Isopropanol (IPA), propanol, decanol, and combinations thereof. If employed, the diluent is typically present in an amount in the range of about 10% (w/w) to about 30% (w/w). Compositions with relatively higher diluent concentrations tend to, but do not necessarily, have lower ion flow values, reduced modulus and increased elongation, and water film break time (WBUT) of greater than or equal to 20 seconds. Other materials suitable for use in the manufacture of hydrogel contact lenses are described in U.S. patent No. 6,867,245, the disclosure of which is incorporated herein by reference in its entirety. However, in certain examples, the polymerizable composition is free of diluent.

Silicone-containing hydrogel contact lenses are often referred to as silicone hydrogel contact lenses. Many silicone hydrogel contact lenses are based on polymerizable lens formulations that include siloxane monomers, macromers, prepolymers, or combinations thereof; and at least one hydrophilic monomer, as previously described. Some examples of silicone hydrogel contact lens materials include materials having the following USANs: echofilcon A (acquafilcon A) or echofilcon B, balafilcon A (balafilcon A), camfelcon A, enfilcon A (enfilcon A), galifilcon A (galyfilcon A), lenefilcon A (lenefilcon A), rhotefilcon A (lotrafilcon A), rhotefilcon B, cronofilcon A (senofilcon A), narafilcon A (narafilcon A) and phenanthrene 3(filcon II 3). In one example, a lens body having ophthalmically acceptably wettable anterior and posterior surfaces without applying a surface treatment to the lens body or without the presence of an Interpenetrating Polymer Network (IPN) of a polymeric wetting agent in the lens body is a camofukan a silicone hydrogel contact lens body.

A method of manufacturing an ophthalmic lens, such as a silicone hydrogel contact lens, is illustrated in fig. 1. According to the present invention, all steps are illustrated in FIG. 1 or a subset of the steps are illustrated in FIG. 1. Items used as inputs, outputs or both inputs and outputs for the steps of fig. 1 are illustrated in fig. 2. Fig. 1 includes a step 102 of placing a polymerizable composition on or in a mold member comprising a polar thermoplastic polymer (i.e., a less polar thermoplastic polymer as described herein) having an average polarity of about 1% to about 7%. According to the present invention, a polymerizable composition can be understood to be a lens precursor composition, such as a polymerizable silicone hydrogel contact lens precursor composition. The polymerizable composition is illustrated in fig. 2 as element 202. Polymerizable compositions are understood to be prepolymerized or precured compositions suitable for polymerization. As used herein, the polymerizable compositions of the present invention may also be referred to as a monomer mixture.

Typically, the polymerizable composition or lens precursor composition is not polymerized prior to curing or polymerizing the composition. However, the polymerizable composition or lens precursor composition can be partially polymerized before undergoing the curing process. In one example, the polymerizable composition can include a polymer component that becomes crosslinked with other components of the polymerizable composition during the curing process. The polymer component can be one that is not a polymeric wetting agent or care agent, does not form an interpenetrating polymer network in the lens body, or is neither a polymeric wetting agent or care agent nor forms an IPN in the lens body.

The lens precursor compositions of the present invention can be provided in a container, dispensing device, or contact lens mold prior to a curing or polymerization procedure as described herein. Referring to fig. 1, in step 102, a lens precursor composition is placed onto a lens forming surface (i.e., the area for molding the lens surface) of a female contact lens mold part (i.e., on the concave lens forming surface). A contact lens female mold member can be understood to be a first contact lens mold member or an anterior contact lens mold member. For example, a female contact lens member has a lens forming surface that defines the anterior or front surface of a contact lens manufactured from a contact lens mold. The second contact lens mold member can be understood to be a contact lens male mold member or a posterior contact lens mold member. For example, the second contact lens mold member comprises a lens forming surface defining the posterior surface of a contact lens manufactured in a contact lens mold (i.e., the second or male mold member has a convex lens forming surface).

Further in accordance with the present invention, the first and second mold members comprise, include, comprise, consist essentially of, or consist of a less polar thermoplastic polymer (e.g., PBT or acetal) as described herein, including a substantial amount of the thermoplastic polymer, and have been made in accordance with the present invention to have a lens-forming surface of a degree of polarity sufficient to make a silicone hydrogel contact lens having an ophthalmically acceptably wettable surface.

The first contact lens mold member is placed in contact with the second contact lens mold member to form a contact lens mold assembly having a contact lens molding cavity. The method illustrated in FIG. 1 comprises the step 104 of completing a contact lens mold assembly by placing two contact lens mold members in contact with each other to form a contact lens mold assembly having a contact lens molding cavity. For example, referring to fig. 2, a polymerizable silicone hydrogel lens precursor composition 202 is located in a contact lens molding cavity.

At step 106, the method illustrated in FIG. 1 includes curing the polymerizable composition to form a polymerized lens body that is not contacted with a liquid and is contained in a mold assembly, as illustrated by element 204 in FIG. 2. In one example, the polymerized lens body is a silicone hydrogel contact lens body that has not been contacted with a liquid. During curing, the components of the polymerizable composition polymerize to form a polymerized lens body. Thus, curing may also be understood as a polymerization step. Curing 106 can include exposing the polymerizable lens precursor composition to a form of electromagnetic radiation effective to polymerize the components of the lens precursor composition. For example, curing 106 can include exposing the polymerizable composition to a polymerizing amount of a form of electromagnetic radiation, such as heat or Ultraviolet (UV) light. Curing 106 may also include curing the composition in an oxygen-free or nearly oxygen-free environment. For example, curing 106 may occur in the presence of nitrogen or other inert gas. Curing 106 can be effective to fully polymerize the polymerizable composition or can polymerize the polymerizable composition to a level that allows the lens body to retain its molded shape suitable for use as a contact lens upon processing (e.g., demolding, delensing, washing, packaging, sterilization, etc.).

Polymeric lens bodies that are not exposed to liquid refer to the polymeric product prior to undergoing an optional washing process and prior to contacting liquid as part of a wet demolding or wet delensing process. For example, the washing process can be a cleaning process that removes dust or debris, an extraction process that removes a portion or substantially all of one or more extractable components from the polymerized lens body, or a hydration process that partially or fully hydrates the hydrogel lens body. For example, polymeric lens products that are not contacted with a liquid can be provided in a lens-shaped cavity of a mold assembly after a curing process; can be provided on or in one contact lens mold member after dry demolding of the contact lens mold; or may be provided on or in an extraction tray or other device after the dry delensing procedure and prior to the washing procedure. In one example, a delensed polymeric lens body that has not been contacted with a liquid, such as a cleaning solution, an extraction solution, a hydration solution, and combinations thereof, can be provided on or in an extraction tray or other device prior to contacting the liquid.

The polymerized lens body that is not exposed to the liquid 204 can include lens-forming components, such as a silicon-containing polymer network or matrix in the shape of a lens; and a removable component that can be removed from the lens body after polymerization. The removable component is understood to include unreacted monomers, oligomers, partially reacted monomers, or other agents that are not covalently attached to or otherwise immobilized relative to the lens-forming component. Removable components can also be understood to include one or more additives, including diluents, that can be removed from the polymerized lens product during a cleaning, extraction, or hydration procedure (as discussed herein). Thus, the material of the removable component may comprise a polymer of the extractable material in a linear uncrosslinked or slightly crosslinked or branched form that is not crosslinked to or otherwise fixed relative to the polymeric backbone, network or matrix of the lens body.

After curing the polymerizable composition, the method illustrated in FIG. 1 includes a step 108 of demolding the mold assembly. Demolding refers to the process of separating two mold members (e.g., male and female) of a mold assembly containing a polymerized lens body. The demolding process holds the polymerized lens body in contact with one and only one of the two mold members used to form the lens body 206. After the demolding process, the polymerized lens body is located on, or remains in contact with, only one mold member of the mold assembly. For example, the polymerized lens body can be on or in contact with a male mold member, or can be on or in contact with a female mold member. When a dry demolding process is used, the resulting polymeric lens body that remains in contact with one mold member 206 is not contacted with a liquid.

During the delensing step, the polymeric lens body that remains in contact with one mold member 206 is released from the one mold member with which it is in contact, as shown in step 110 of FIG. 1. Depending on the mold parts with which the polymerized lens body remains in contact after the demolding step 108, the lens body can be delensed from either the male or female mold parts. After the delensing step, the released lens body is a delensing lens body 208. When a dry delensing process is performed after the dry demolding process, the resulting delensing polymeric lens body is a delensing polymeric lens body that has not been contacted with a liquid.

The method illustrated in fig. 1 optionally includes a step 112 of washing the lens body by contacting the polymerized lens body with a liquid (e.g., an organic solvent solution, water, or an aqueous solution) to clean dust or debris in the lens body, to extract the lens body to remove extractable material from the lens body, or to fully or partially hydrate the lens body. The washing step 112 results in a cleaned, extracted, or hydrated lens body 210, as shown in fig. 2. The washing step 112 can optionally be performed on a mold assembly comprising a polymeric lens body, a polymeric lens body that remains in contact with one mold member 206, a delensed lens body 208, and can be repeated during the manufacturing process.

After optional washing of the polymeric lens body, the method may optionally include a step 114 of hydrating the polymeric lens body. The hydration step 114 may include contacting the polymerized lens body, or one or more batches of the lens bodies, with water or an aqueous solution to form a hydrated lens product, such as a silicone hydrogel contact lens 212, as shown in fig. 2. The hydrating step can completely or partially hydrate the lens body. In one example, the polymerized lens body hydrated in step 114 is a delensed polymerized lens body that has not been contacted with a liquid prior to the hydration step 114. In another example, the polymeric lens body hydrated in step 114 is a polymeric lens body that remains in contact with one mold part 206 that was not contacted with a liquid prior to the hydration step 114. In this example, the hydration step 114 can serve as both the hydration step 114 and the delensing step 110. In another example, the polymeric lens body hydrated in step 114 can be the polymeric lens body in the mold assembly 204. In this example, the polymeric lens body hydrated in step 114 is a polymeric lens body contained in the mold assembly that has not previously contacted a liquid, and the hydration step 114 can be used as the demolding step 108 as well as part or all of the hydration step 114.

After demolding and optionally washing and/or hydrating the polymeric lens body, the method illustrated in fig. 1 may optionally include a step 116 of packaging the lens body to produce a packaged ophthalmic lens product 214. For example, the lens body can be placed in a blister pack, vial, or other suitable container with a volume of a packaging liquid (e.g., a physiological saline solution, including a buffered physiological saline solution). In one example, the hydrating step 114 and the packaging step can be performed simultaneously by placing the polymeric lens body that has not previously contacted the liquid into a blister pack or container having a portion of the packaging liquid used as both the packaging liquid and the hydrating solution. The polymeric lens body that is hydrated and packaged simultaneously in this example can be a delensed polymeric lens body that has not previously contacted a liquid, or a polymeric lens body that remains in contact with one mold member and has not previously contacted a liquid, with both lens bodies and the one mold member being placed in a package.

The blister pack or container with the packaged ophthalmic lens product 214 can be sealed and subsequently sterilized, as shown in optional step 118 of fig. 1. For example, the packaged ophthalmic lens may be exposed to a sterilizing amount of radiation, including heat (e.g., by autoclaving), gamma radiation, electron beam radiation, ultraviolet radiation, and the like. Depending on the process steps previously used, the sterilization process may also be used to partially or fully extract, fully hydrate, or extract and hydrate the packaged ophthalmic lens body.

The invention includes the following aspects/embodiments/features in any order and/or in any combination:

1. the present invention relates to a method of manufacturing a silicone hydrogel contact lens body, comprising:

providing a first mold member and a second mold member, the first mold member comprising a concave molding surface configured to mold an anterior surface of a contact lens and the second mold member comprising a convex molding surface configured to mold a posterior surface of a contact lens, the molding surface of at least one of the first mold member and the second mold member comprising at least one polar thermoplastic polymer having an average polarity of from about 1% to about 7%, the first mold member and the second mold member configured to form a lens-shaped cavity therebetween when combined into a mold assembly;

placing a polymerizable composition into the first mold member, the polymerizable composition comprising a) at least one silicone monomer, silicone macromer, silicone prepolymer, or combination thereof, and b) at least one hydrophilic monomer;

assembling the mold assembly by placing the second mold member in contact with the first mold member, thereby forming a lens-shaped cavity therebetween, wherein the polymerizable composition is contained in the lens-shaped cavity of the mold assembly;

curing the polymerizable composition in the mold assembly to form a cast-molded polymerization reaction product in the lens-shaped cavity of the mold assembly, the polymerization reaction product comprising a silicone hydrogel contact lens body;

wherein the lens body has ophthalmically acceptably wettable front and back surfaces without the need for applying a surface treatment to the lens body or the presence of an interpenetrating network (IPN) of a polymeric wetting agent in the lens body.

2. The method of any preceding or subsequent embodiment/feature/aspect, wherein at least one of the first molded member and the second molded member comprising the at least one polar thermoplastic polymer is formed by injection molding, and a mold tool used to form the mold member is maintained at a temperature of about 30 ℃ to about 70 ℃ during the injection molding.

3. The method of any preceding or following embodiment/feature/aspect, wherein method further comprises the step of separating the mold assembly, wherein the separating holds the lens body in contact with one and only one of the first mold member and the second mold member.

4. The method of any preceding or following embodiment/feature/aspect, wherein the step of separating the mold assembly comprises using a dry demolding method that does not involve applying a liquid to the mold assembly containing the lens body.

5. The method of any preceding or following embodiment/feature/aspect, wherein the method further comprises the step of releasing the lens body from the one and only one of the first mold member and the second mold member using a dry delensing method that does not involve applying a liquid to the lens body.

6. The method of any preceding or following embodiment/feature/aspect, wherein the method further comprises the step of washing the released lens body in an aqueous solution substantially free of volatile organic solvent to produce a washed lens body.

7. The method of any preceding or following embodiment/feature/aspect, wherein the method further comprises hydrating the lens body, and after hydration, the silicone hydrogel contact lens body has an advancing contact angle of less than about 100 °.

8. The method of any preceding or subsequent embodiment/feature/aspect, wherein the at least one polar thermoplastic polymer comprises polybutylene terephthalate (PBT).

9. The method of any preceding or following embodiment/feature/aspect, wherein the thermoplastic polymer further comprises at least one additive selected from the group consisting of: free fatty acids, fatty acid esters, metal salts of fatty acids, and combinations thereof.

10. The method of any preceding or subsequent embodiment/feature/aspect, wherein the polymerizable composition and the molding surface of at least one of the first mold member and the second mold member have a spreading coefficient greater than or equal to about 13 mN/m.

11. The method of any preceding or subsequent embodiment/feature/aspect, wherein the hydrophilic monomer in the polymerizable composition comprises a hydrophilic monomer having an N-vinyl group.

12. The method of any preceding or subsequent embodiment/feature/aspect, wherein the polymerizable composition further comprises a UV initiator, and the step of curing the polymerizable composition in the mold assembly comprises applying UV light to polymerize the polymerizable composition.

13. The method of any preceding or following embodiment/feature/aspect, wherein the yield of acceptable lens bodies using the method is higher than the yield of acceptable lens bodies made using substantially the same method but using first and second mold members each having a molding surface with an average polarity greater than or equal to 9%.

14. A silicone hydrogel contact lens body, comprising:

a cast-molded polymerized lens body comprising the reaction product of a polymerizable composition comprising a) at least one silicone monomer, silicone macromer, silicone prepolymer, or combination thereof, and b) at least one hydrophilic monomer;

wherein the lens body is cast molded in a mold assembly comprising a first mold member and a second mold member, at least one molding surface of the first mold member and the second mold member comprising at least one polar thermoplastic polymer having an average polarity of about 1% to about 7%; and is

The lens body has ophthalmically acceptably wettable front and back surfaces without the need for applying a surface treatment to the lens body or the presence of an interpenetrating network (IPN) of a polymeric wetting agent in the lens body.

15. A mold member for cast molding a silicone hydrogel contact lens body, wherein the mold member comprises at least one polar thermoplastic polymer having an average polarity of from about 1% to about 7%, and the area of the mold member used to form the lens surface has a total surface energy of greater than or equal to about 32 mN/m.

The invention may comprise any combination of the different features or embodiments above and/or below as stated in sentences and/or paragraphs. Any combination of features disclosed herein is considered part of the invention and is not intended to be limiting with respect to the combinable features.

The following non-limiting examples illustrate certain aspects of the present methods and apparatus.

Example 1(comparative example, theory)

Some polar thermoplastic polymers in the form of granules or pellets having an average polarity greater than or equal to 9% are provided. A portion of the polymer is processed by conventional injection molding into a contact lens mold member. Polymerizable compositions for making silicone hydrogel contact lenses are prepared as described herein, and used to prepare a plurality of cast-molded polymerized silicone hydrogel lens bodies, as illustrated in fig. 1. The polymerizable composition has an average polarity of about 1% to about 7%. The mold assembly comprising the polymerizable composition is cured using heat or UV radiation. After curing, the mold assembly comprising the cast-molded polymeric lens body is dry demolded to separate the two mold members of the mold assembly. It is difficult, if not impossible, to separate the two mold members of a mold assembly to obtain one mold member having a polymeric lens body of acceptable quality for use as a contact lens, which polymeric lens body remains in contact with the one mold member. The yield of demolded mold parts in contact with lens bodies of acceptable quality is less than about 10%. After the dry demolding step, the polymerized lens body is released from one of the mold parts it remains in contact with after the demolding step using a wet delensing process. Subsequently, the released lens body is washed sequentially with a liquid comprising an organic solvent and an aqueous solution substantially free of an organic solvent, or with an aqueous solution substantially free of an organic solvent. The washing step may include an additional hydration step, or may include a separate hydration step prior to packaging and sterilization of the lens body. The lens body is not treated with a surface treatment to increase wettability and is free of an interpenetrating network of a polymeric wetting agent. Once the lens body is fully hydrated, it has an ophthalmically acceptably wettable surface.

Example 2(comparative example)

Providing a quantity of SOARLITE in the form of granules or pellets^TMS ethylene vinyl alcohol (EVOH) polymer (japan synthetic chemical industry limited, osaka, japan). It has been found that SOARLITE^TMS has an average polarity of about 10% to about 12% and an average surface energy of about 38 mN/m. A portion of the polymer is processed by conventional injection molding into a contact lens mold member. A polymerizable composition for making a camnfika lens is prepared and used to prepare a plurality of cast-molded polymerized silicone hydrogel lens bodies, as illustrated in fig. 1. The average polarity of the camfenicon a polymerizable composition is about 5%. When using a composition comprising SOARLITE^TMS mold Assembly for cast molding Carmfekon A lensesThe polymerizable composition now had a spreading factor of about 12, and after curing, the mold assembly was found to have an average adhesion energy of about 58mJ/m². After UV curing, the mold assembly comprising the cast-molded polymeric lens body is dry demolded to separate the two mold members of the mold assembly. It is difficult, if not impossible, to separate the two mold members of a mold assembly to obtain one mold member having a polymeric lens body of acceptable quality for use as a contact lens, which polymeric lens body remains in contact with the one mold member. The yield of demolded mold parts in contact with lens bodies of acceptable quality is less than or equal to about 10%. After the dry demolding step, the polymerized lens body is released from one of the mold parts it remains in contact with after the demolding step using a wet delensing process. The released lens bodies are then washed with an aqueous solution substantially free of organic solvents, and then packaged and sterilized. The lens body is not treated with a surface treatment to increase wettability and is free of an interpenetrating network of a polymeric wetting agent. Once the lens body is fully hydrated, it has an ophthalmically acceptably wettable surface. The WBUT of the lenses was measured to be about 52 seconds and the sessile drop contact angle of the lenses was measured to be about 35 °.

Example 3(theory)

Some polar thermoplastic polymers are provided in the form of granules or pellets having an average polarity of about 1% to about 7%. A portion of the polymer is processed by conventional injection molding into a contact lens mold member. Polymerizable compositions for making silicone hydrogel contact lenses are prepared and used to prepare a plurality of cast-molded polymerized silicone hydrogel lens bodies, as illustrated in fig. 1. After UV or thermal curing, the mold assembly comprising the cast-molded polymeric lens body is dry demolded to separate the two mold members of the mold assembly. The mold assembly is readily dry demolded to obtain one mold member having a polymeric lens body of acceptable quality for use as a contact lens, which polymeric lens body remains in contact with the one mold member. The yield of demolded mold parts in contact with lens bodies of acceptable quality is greater than or equal to about 50%. After the dry demolding step, the polymerized lens body is released from one of the mold parts it remains in contact with after the demolding step using a wet delensing process. Subsequently, the released lens body is washed sequentially with a liquid comprising an organic solvent and an aqueous solution substantially free of an organic solvent, or with an aqueous solution substantially free of an organic solvent. The washing step may include an additional hydration step, or may include a separate hydration step prior to packaging and sterilization of the lens body. The lens body is not treated with a surface treatment to increase wettability and is free of an interpenetrating network of a polymeric wetting agent. Once the lens body is fully hydrated, it has an ophthalmically acceptably wettable surface.

Example 4(theory)

Some polar thermoplastic polymers are provided in the form of granules or pellets having an average polarity of about 1% to about 7%. A portion of the polymer is processed by conventional injection molding into a contact lens mold member. Polymerizable compositions for making silicone hydrogel contact lenses are prepared and used to prepare a plurality of cast-molded polymerized silicone hydrogel lens bodies, as illustrated in fig. 1. After UV or thermal curing, the mold assembly comprising the cast-molded polymeric lens body is dry demolded to separate the two mold members of the mold assembly. The mold assembly is readily dry demolded to obtain one mold member having a polymeric lens body of acceptable quality for use as a contact lens, which polymeric lens body remains in contact with the one mold member. The yield of demolded mold parts in contact with lens bodies of acceptable quality is greater than or equal to about 50%. After the dry demolding step, the polymerized lens body is released from one of the mold parts it remains in contact with after the demolding step using a dry delensing process. Subsequently, the released lens body is washed sequentially with a liquid comprising an organic solvent and an aqueous solution substantially free of an organic solvent, or with an aqueous solution substantially free of an organic solvent. The washing step may include an additional hydration step, or may include a separate hydration step prior to packaging and sterilization of the lens body. The lens body is not treated with a surface treatment to increase wettability and is free of an interpenetrating network of a polymeric wetting agent. Once the lens body is fully hydrated, it has an ophthalmically acceptably wettable surface.

Example 5(theory)

Some polar thermoplastic polymers are provided in the form of granules or pellets having an average polarity of about 1% to about 7%. A portion of the polymer is processed by conventional injection molding into a contact lens mold member. Polymerizable compositions having an average polarity of about 1% to about 7% and formulated for use in the manufacture of silicone hydrogel contact lenses are prepared and used to prepare a plurality of cast-molded polymerized silicone hydrogel lens bodies, as illustrated in fig. 1. After UV or thermal curing, the mold assembly comprising the cast-molded polymeric lens body is dry demolded to separate the two mold members of the mold assembly. The mold assembly is readily dry demolded to obtain one mold member having a polymeric lens body of acceptable quality for use as a contact lens, which polymeric lens body remains in contact with the one mold member. The yield of demolded mold parts in contact with lens bodies of acceptable quality is greater than or equal to about 50%. After the dry demolding step, the polymerized lens body is released from one of the mold members with which it remains in contact after the demolding step using either a wet delensing process or a dry delensing process. Subsequently, the released lens body is washed sequentially with a liquid comprising an organic solvent and an aqueous solution substantially free of an organic solvent, or with an aqueous solution substantially free of an organic solvent. The washing step may include an additional hydration step, or may include a separate hydration step prior to packaging and sterilization of the lens body. The lens body is not treated with a surface treatment to increase wettability and is free of an interpenetrating network of a polymeric wetting agent. Once the lens body is fully hydrated, it has an ophthalmically acceptably wettable surface.

Example 6

Providing a quantity of CELANEX in the form of granules or pellets2000-2PBT polymer (Ticona, Florence, KY, USA, Kentucky). CELANEX2000-2 is unreinforced polybutylene terephthalate with an internal lubricant. It is reported to have a melting temperature of about 225 ℃ when measured at a rate of 10 ℃/min using ISO11357-1, ISO11357-2, ISO11357-3, and a glass transition temperature of less than about 60 ℃ when measured at a rate of 10 ℃/min using ISO11357-1, ISO11357-2, ISO 11357-3. CELANEX has been discovered2000-2 has an average polarity of about 3%, an average surface energy of about 38mN/m and a glass transition temperature of about 46.7 ℃. A portion of the polymer is processed by conventional injection molding into a contact lens mold member. A polymerizable composition for making a camnfika lens is prepared and used to prepare a plurality of cast-molded polymerized silicone hydrogel lens bodies, as illustrated in fig. 1. The average polarity of the camfenicon a polymerizable composition is about 5%. When using a system comprising CELANEX2000-2 mold assembly for cast molding a Carmfekon A lens, the polymerizable composition was found to have a spreading factor of about 13, and after curing, the mold assembly was found to have an average adhesion energy of about 59mJ/m². After UV curing, the mold assembly comprising the cast-molded polymeric lens body is dry demolded to separate the two mold members of the mold assembly. The mold assembly is readily dry demolded to obtain one mold member having a polymeric lens body of acceptable quality for use as a contact lens, which polymeric lens body remains in contact with the one mold member.The yield of demolded mold parts in contact with lens bodies of acceptable quality is greater than or equal to about 50%. After the dry demolding step, the polymerized lens body is released from one of the mold parts it remains in contact with after the demolding step using a wet delensing process. The released lens bodies are then washed with an aqueous solution substantially free of organic solvents, and then packaged and sterilized. The lens body is not treated with a surface treatment to increase wettability and is free of an interpenetrating network of a polymeric wetting agent. Once the lens body is fully hydrated, it has an ophthalmically acceptably wettable surface. The WBUT of the lenses was measured to be about 26 seconds and the sessile drop contact angle of the lenses was measured to be about 26 °.

Example 7

Providing a quantity of ARNITE in the form of granules or pelletsT06-202PBT polymer (DSM, Hollanden, Heerlen, the Netherlands). ARNITE (R) saltT06-202 is a medium viscosity form of polybutylene terephthalate suitable for injection molding. The deflection temperature was about 55 ℃ under a load of 1.80MPa and about 165 ℃ under a load of 0.45MPa, both measured using ISO75-1, ISO 75-2. It has been found that ARNITET06-2022 had an average polarity of about 3% and an average total surface energy of about 38 mN/m. A portion of the polymer is processed by conventional injection molding into a contact lens mold member. A polymerizable composition for making a camnfika lens is prepared and used to prepare a plurality of cast-molded polymerized silicone hydrogel lens bodies, as illustrated in fig. 1. The average polarity of the camfenicon a polymerizable composition is about 5%. When using a composition comprising ARNITEWhen the mold assembly of T06-2022 was used to cast mold a Carmfekon A lens, the spreading factor of the polymerizable composition was found to be about 13, and after curing, the average adhesion energy of the mold assembly was found to be about 59mJ/m². After UV curing, the mold assembly comprising the cast-molded polymeric lens body is dry demolded to separate the two mold members of the mold assembly. The mold assembly is readily dry demolded to obtain one mold member having a polymeric lens body of acceptable quality for use as a contact lens, which polymeric lens body remains in contact with the one mold member. The yield of demolded mold parts in contact with lens bodies of acceptable quality is greater than or equal to about 50%. After the dry demolding step, the polymerized lens body is released from one of the mold parts it remains in contact with after the demolding step using a wet delensing process. The released lens bodies are then washed with an aqueous solution substantially free of organic solvents, and then packaged and sterilized. The lens body is not treated with a surface treatment to increase wettability and is free of an interpenetrating network of a polymeric wetting agent. Once the lens body is fully hydrated, it has an ophthalmically acceptably wettable surface. The WBUT of the lenses was measured to be about 35 seconds and the sessile drop contact angle of the lenses was measured to be about 19 °.

Example 8

Providing CRASTIN in the form of granules or pelletsFGS600F40NC010PBT polymer (dupont, wilmington, terawa, usa). CRASTINThe FGS600F40NC010 is an unreinforced, low viscosity form of polybutylene terephthalate suitable for injection molding. The melting temperature was about 437 deg.C as measured using ISO 11357-3. In the unannealed case, the deflection temperature was about 239 ℃ at 66psi and about 356 ℃ at 264psi as measured using ISO 75-2/B. It has been found that CRASTINThe FGS600F40NC010 had an average polarity of about 7% and an average total surface energy of about 41 mN/m. A portion of the polymer is processed by conventional injection molding into a contact lens mold member. A polymerizable composition for making a camnfika lens is prepared and used to prepare a plurality of cast-molded polymerized silicone hydrogel lens bodies, as illustrated in fig. 1. The average polarity of the camfenicon a polymerizable composition is about 5%. When using a pharmaceutical composition containing CRASTINWhen a mold assembly of FGS600F40NC010 was used to cast mold a Carmfekon A lens, the spreading factor of the polymerizable composition was found to be about 15, and after curing, the average adhesion energy of the mold assembly was found to be about 61mJ/m². After UV curing, the mold assembly comprising the cast-molded polymeric lens body is dry demolded to separate the two mold members of the mold assembly. The mold assembly is readily dry demolded to obtain one mold member having a polymeric lens body of acceptable quality for use as a contact lens, which polymeric lens body remains in contact with the one mold member. The yield of demolded mold parts in contact with lens bodies of acceptable quality is greater than or equal to about 50%. After the dry demolding step, the polymerized lens body is released from one of the mold parts it remains in contact with after the demolding step using a wet delensing process. The released lens bodies are then washed with an aqueous solution substantially free of organic solvents, and then packaged and sterilized. The lens body is not treated with a surface treatment to increase wettability and is free of an interpenetrating network of a polymeric wetting agent. Once the lens body is fully hydrated, it has an ophthalmically acceptably wettable surface. The WBUT of the lenses was measured to be about 55 seconds and the sessile drop contact angle of the lenses was measured to be about 15 °.

Example 9

Some acetal polymers are provided in the form of granules or pellets. A portion of the polymer is processed by conventional injection molding into a contact lens mold member. A polymerizable composition for making a camnfika lens is prepared and used to prepare a plurality of cast-molded polymerized silicone hydrogel lens bodies, as illustrated in fig. 1. The average polarity of the camfenicon a polymerizable composition is about 5%. After UV or thermal curing, the mold assembly comprising the cast-molded polymeric lens body is dry demolded to separate the two mold members of the mold assembly. The mold assembly is readily dry demolded to obtain one mold member having a polymeric lens body of acceptable quality for use as a contact lens, which polymeric lens body remains in contact with the one mold member. The yield of demolded mold parts in contact with lens bodies of acceptable quality is greater than or equal to about 50%. After the dry demolding step, the polymerized lens body is released from one of the mold parts it remains in contact with after the demolding step using a wet delensing process. The released lens bodies are then washed with an aqueous solution substantially free of organic solvents, and then packaged and sterilized. The lens body is not treated with a surface treatment to increase wettability and is free of an interpenetrating network of a polymeric wetting agent. Once the lens body is fully hydrated, it has an ophthalmically acceptably wettable surface.

Example 10(theory)

A mixture of a polar thermoplastic polymer and a non-polar thermoplastic polymer having an average polarity of from about 1% to about 7% in the form of granules or pellets is provided. A portion of the polymer mixture is processed by conventional injection molding into a contact lens mold member. The average polarity of the molding surface of the mold member is from about 1% to about 7%. Polymerizable compositions formulated for the manufacture of silicone hydrogel contact lenses are prepared and used to prepare a plurality of cast-molded polymerized silicone hydrogel lens bodies, as illustrated in fig. 1. After UV or thermal curing, the mold assembly comprising the cast-molded polymeric lens body is dry demolded to separate the two mold members of the mold assembly. The mold assembly is readily dry demolded to obtain one mold member having a polymeric lens body of acceptable quality for use as a contact lens, which polymeric lens body remains in contact with the one mold member. The yield of demolded mold parts in contact with lens bodies of acceptable quality is greater than or equal to about 50%. After the dry demolding step, the polymerized lens body is released from one of the mold members with which it remains in contact after the demolding step using either a wet delensing process or a dry delensing process. Subsequently, the released lens body is washed sequentially with a liquid comprising an organic solvent and an aqueous solution substantially free of an organic solvent, or with an aqueous solution substantially free of an organic solvent. The washing step may include an additional hydration step, or may include a separate hydration step prior to packaging and sterilization of the lens body. The lens body is not treated with a surface treatment to increase wettability and is free of an interpenetrating network of a polymeric wetting agent. Once the lens body is fully hydrated, it has an ophthalmically acceptably wettable surface.

Example 11(theory)

Providing a mixture of a polar thermoplastic polymer having an average polarity greater than about 9% and a non-polar thermoplastic polymer in the form of granules or pellets. A portion of the polymer mixture is processed by conventional injection molding into a contact lens mold member. The average polarity of the molding surface of the mold member is from about 1% to about 7%. Polymerizable compositions formulated for the manufacture of silicone hydrogel contact lenses are prepared and used to prepare a plurality of cast-molded polymerized silicone hydrogel lens bodies, as illustrated in fig. 1. After UV or thermal curing, the mold assembly comprising the cast-molded polymeric lens body is dry demolded to separate the two mold members of the mold assembly. The mold assembly is readily dry demolded to obtain one mold member having a polymeric lens body of acceptable quality for use as a contact lens, which polymeric lens body remains in contact with the one mold member. The yield of demolded mold parts in contact with lens bodies of acceptable quality is greater than or equal to about 50%. After the dry demolding step, the polymerized lens body is released from one of the mold members with which it remains in contact after the demolding step using either a wet delensing process or a dry delensing process. Subsequently, the released lens body is washed sequentially with a liquid comprising an organic solvent and an aqueous solution substantially free of an organic solvent, or with an aqueous solution substantially free of an organic solvent. The washing step may include an additional hydration step, or may include a separate hydration step prior to packaging and sterilization of the lens body. The lens body is not treated with a surface treatment to increase wettability and is free of an interpenetrating network of a polymeric wetting agent. Once the lens body is fully hydrated, it has an ophthalmically acceptably wettable surface.

While the methods and apparatus have been described with reference to various specific examples, it is to be understood that the disclosure is not so limited and that the methods and apparatus may be practiced otherwise than as specifically described within the scope of the claims.

Applicants specifically incorporate the entire contents of all cited references in this disclosure. Further, when an amount, concentration, or other value or parameter is given as either a range, preferred range, or a list of upper preferable values and lower preferable values, this is to be understood as specifically disclosing all ranges formed from any pair of any upper range limit or preferred value and any lower range limit or preferred value, regardless of whether ranges are separately disclosed. When a range of numerical values is recited herein, unless otherwise specified, the range is intended to include the endpoints thereof, and all integers and fractions within the range. The scope of the invention is not intended to be limited to the specific values recited when defining a range.

Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims and their equivalents.

Claims (17)

1. A method of manufacturing a silicone hydrogel contact lens body, comprising:

providing a first mold member and a second mold member, the first mold member comprising a concave molding surface configured to mold an anterior surface of a contact lens and the second mold member comprising a convex molding surface configured to mold a posterior surface of a contact lens, the molding surface of at least one of the first mold member and the second mold member comprising at least one polar thermoplastic polymer having an average polarity of 1% to 7%, the first mold member and the second mold member configured to form a lens-shaped cavity therebetween when combined into a mold assembly;

placing a polymerizable composition into the first mold member, the polymerizable composition comprising a) at least one silicone monomer, silicone prepolymer, or a combination thereof, and b) at least one hydrophilic monomer;

assembling the mold assembly by placing the second mold member in contact with the first mold member to form a lens-shaped cavity therebetween, wherein the polymerizable composition is contained in the lens-shaped cavity of the mold assembly;

curing the polymerizable composition in the mold assembly to form a cast-molded polymerization reaction product in the lens-shaped cavity of the mold assembly, the polymerization reaction product comprising a silicone hydrogel contact lens body;

wherein the lens body has ophthalmically acceptably wettable front and back surfaces, no surface treatment is applied to the lens body, or no interpenetrating network (IPN) of a polymeric wetting agent is present in the lens body.

2. The method of claim 1, wherein at least one of the first molded member and the second molded member comprising the at least one polar thermoplastic polymer is formed by injection molding, and a mold tool used to form the mold member is maintained at a temperature of 30-70 ℃ during the injection molding.

3. The method of claim 1, wherein method further comprises the step of separating the mold assembly, wherein the separation maintains the lens body in contact with one and only one of the first mold member and the second mold member.

4. The method of claim 3, wherein the step of separating the mold assembly comprises using a dry demolding method that does not involve applying a liquid to the mold assembly containing the lens body.

5. The method of claim 4, wherein the method further comprises the step of releasing the lens body from the one and only one of the first mold member and the second mold member using a dry delensing method that does not involve applying a liquid to the lens body.

6. The method of claim 1, wherein the method further comprises the step of washing the released lens body in an aqueous solution substantially free of volatile organic solvents to produce a washed lens body.

7. The method of claim 1, wherein the method further comprises hydrating the lens body, and after hydration, the silicone hydrogel contact lens body has an advancing contact angle of less than 100 °.

8. The process of claim 1, wherein the at least one polar thermoplastic polymer comprises polybutylene terephthalate (PBT).

9. The method of claim 1, wherein the thermoplastic polymer further comprises at least one additive selected from the group consisting of: free fatty acids, fatty acid esters, metal salts of fatty acids, and combinations thereof.

10. The method of claim 1, wherein the polymerizable composition and the molding surface of at least one of the first and second mold members have a spreading coefficient greater than or equal to 13 mN/m.

11. The method of claim 1, wherein the hydrophilic monomer in the polymerizable composition comprises a hydrophilic monomer having an N-vinyl group.

12. The method of claim 1, wherein the polymerizable composition further comprises a UV initiator, and the step of curing the polymerizable composition in the mold assembly comprises applying UV light to polymerize the polymerizable composition.

13. The method of claim 1, wherein the yield of acceptable lens bodies using the method is higher than the yield of acceptable lens bodies made using substantially the same method but using first and second mold members each having a molding surface with an average polarity greater than or equal to 9%.

14. The method of claim 1, wherein the polymerizable composition comprises a silicone macromer.

15. A silicone hydrogel contact lens body, comprising:

a cast-molded polymerized lens body comprising the reaction product of a polymerizable composition comprising a) at least one silicone monomer, silicone prepolymer, or combination thereof, and b) at least one hydrophilic monomer;

wherein the lens body is cast molded in a mold assembly comprising a first mold member and a second mold member, at least one molding surface of the first mold member and the second mold member comprising at least one polar thermoplastic polymer having an average polarity of 1% to 7%; and is

The lens body has ophthalmically acceptably wettable front and back surfaces, no surface treatment is applied to the lens body, or no interpenetrating network (IPN) of a polymeric wetting agent is present in the lens body.

16. The silicone hydrogel contact lens body of claim 15, wherein the polymerizable composition comprises a silicone macromer.

17. A mold member for cast molding a silicone hydrogel contact lens body, wherein the mold member comprises polybutylene terephthalate resin, wherein the mold member has an average polarity of 1% to 7%, and the area of the mold member used to form the lens surface has a total surface energy of greater than or equal to 32 mN/m.