MXPA99008794A - Molding processes - Google Patents

Abstract

Efficient and consistent processes for manufacturing moldings, especially ophthalmic lenses such as contact lenses. The processes comprise a series of improvements, including improvements in the areas of conditions for dispensing liquid prepolymer into lens molds, male and female mold mating, reusable molds, mold cleaning, lens separation from molds (demolding), lens handling, and in-line inspection. Cyclic series of processing steps are also disclosed. Additionally, an improved molding tool is disclosed, with the molding tool including a male mold housing and a female mold housing, each of which has disposed therein a plurality of mold halves.

Description

MOLDING PROCESSES The invention relates largely to molding technology. More specifically, this invention relates to processes for molding ophthalmic lenses. In a preferred embodiment, the invention relates to processes for molding contact lenses. The formation of articles by the metering of a liquid polymerizable material and / or crosslinkable in a mold, has been used in a wide variety of technological areas. The molding of medical devices such as ophthalmic lenses is of particular interest. One type of ophthalmic lens that is widely used for vision correction is the contact lens. Contact lenses are manufactured through a number of processes. A traditional lens manufacturing approach is to form a lens preform by polymerizing liquid monomers in a lens preform mold, and then the lens preform is mechanically machined to obtain a finished contact lens. Normally, these turned lenses undergo a subsequent polishing step to remove the imperfections generated during the turning process. More recently, two-sided molding (DSM) processes have been developed. These processes normally involve dosing a liquid monomer into a female mold half, coupling a male mold half with the female, and then applying radiation ultraviolet to polymerize the monomers. The polymerized lens removed from the molds in a two-sided molding process usually does not require surface polishing, but the subsequent extraction of the unreacted monomer or solvent is commonly required. U.S. Patent No. 5,508,317, issued to Beat Müller on April 16, 1996, discloses remarkable improvements in the chemistry of the polymerizable material for molding ophthalmic lenses, by providing a contact lens molding method without the need to remove unreacted monomer or solvent. This patent disclosed a prepolymer composition soluble in water, which can be dosed in a lens mold, and can be crosslinked to form a contact lens of optical quality finished in a matter of seconds, without the need for subsequent extraction steps. European Patent Application Number 637,490, published on February 8, 1995, discloses some outstanding methods for molding the prepolymer materials of U.S. Patent No. 5,508,317. "One embodiment of the invention involves introducing crosslinkable material into a mold of two parts, where the mold halves are kept at a small distance from each other, in such a way that an annular gap is formed between them.The gap is in fluid communication with the cavity of the mold, such way that excess prepolymer can escape through the gap. The crosslinking of the prepolymer is presented by the application of radiation, for example, ultraviolet light, the impact of the radiation being restricted to the mold cavity by masking, that is, by blocking the impact of light, on the areas outside the mold cavity. . The molding teachings of U.S. Patent Application Number 08 / 274,942, Hagmann et al., Are incorporated herein by reference. However, improvements in the efficiency of the molding processes are always desirable. Consequently, there is a need for improvements in the production process by molding, which reduce the time of the product cycle, increase the quality of the finished product, improve the consistency of the product, and reduce the consumption of materials from the product. prosecution. The addition, reductions in the impact on the environment are always desirable, for example, by reducing the number of molds that must be recycled and / or disposed of. An object of the invention is to improve the efficiency of the molding processes, especially the molding processes of contact lenses. Another object of the invention is to increase the consistency and quality of the molding processes, especially the molding processes of contact lenses.

A further object of the invention is to reduce the amount of materials consumed in the molding processes, especially in the molding processes of contact lenses. Still another object of the invention is to reduce the impact to the environment of the molding processes, especially the processes of molding contact lenses. These objects and other advantages are achieved by the different embodiments of the invention described in detail herein. One embodiment of the invention is a process for the semi-continuous production of ophthalmic lenses, which includes a cyclic portion in which the mold halves are continuously reused for a number of cycles. Yet another embodiment of the invention is a process for dosing a crosslinkable material in a mold half, wherein the dosage is conducted: (a) in an atmosphere having a relative humidity of at least 55 percent (preferably about 60 percent to approximately 80 percent); (b) at a height of about 0.1 millimeters to about 5 millimeters from a surface of a mold half (preferably about 1 to 3 millimeters, and more preferably about 1.5 to 2.5 millimeters); and (c) at a horizontal distance of about 1 to about 6 millimeters (preferably about 4 to 6 millimeters) from the central axis of symmetry of the half of the mold. Yet another embodiment of the invention is a process for coupling a male mold half and a female mold half in a two-step movement, which includes: (1) angularly articulating one half of the mold towards the other half of the mold on a angle from about 90 ° to about 270 ° (preferably about 180 °), followed by (2) moving the first half of the mold towards the other (or moving both mold halves towards each other) in a substantially linear movement, while the mold surfaces are substantially parallel to each other. A further embodiment of the invention is a molding assembly that houses a plurality of male and female mold halves. The molding assembly housing includes: (a) a male molding assembly housing a plurality of male mold halves removably affixed thereto; and (b) a female molding assembly that houses a plurality of female mold halves removably attached thereto. The assemblies are fixed to each other, such that the male assembly can be pivoted to a position where the male and female mold halves are essentially parallel to one another, and can then be moved in a linear direction in order to dock them Still an additional modality is a process to inspect the peripheral areas of an ophthalmic lens, which it is held in a central area of the lens and stabilized, preferably both centrally and peripherally. The peripheral inspection process includes the steps of: (a) fastening and stabilizing an ophthalmic lens in a central region; (b) illuminating a peripheral region of the ophthalmic lens; (c) forming an image of the peripheral region of the ophthalmic lens with a camera element; and (d) evaluating the image in order to determine if a lens is rejected and / or the process parameters are adjusted. Yet a further embodiment of the invention is a process for producing a finished ophthalmic lens product from a crosslinkable and / or polymerizable material, which is completed in less than about 20 minutes. Figure 1 is a schematic illustration of a process flow configuration according to one embodiment of the invention. Figure 2A illustrates a plan view of one embodiment of a molding tool in the open position. Figure 2B shows an end section view of the embodiment of the molding tool of Figure 2A in the open position. Figure 2C shows an end section view of the embodiment of the molding tool of Figure 2A in the closed position. Figure 3 illustrates a configuration mode for dosing the prepolymer in a lens mold half. Figure 4 shows an embodiment of the inspection step of the central body of the lens of the invention. Figure 5A shows an end sectional view of the initial linear movement of the male mold half in the mold opening passage. Figure 5B shows an end section view of the final hinge of the male mold half in the mold opening passage. Figure 6 shows a sectional view of an embodiment of the cleaning step of the mold half, which occurs subsequent to the molding. Figures 7A-C illustrate the movement of a lens from the half of the male mold to the half of the female mold in a side sectional view. Figure 8 shows a sectional view of an inspection process for inspecting the periphery of an ophthalmic lens. One embodiment of the invention is a process for the continuous production of ophthalmic lenses, wherein a portion is cyclic, and where half or half of the mold is reused, i.e., recycled to the process by a number of cycles . The different embodiments of the invention are described with respect to the preferred ophthalmic lens modality; however, different embodiments of the invention are not limited to a specific type of molded article. "Ophthalmic lenses", as used herein, refers to any vision correction devices or medical devices that are used in the ocular environment, including contact lenses, infraocular lenses, overlays and corneal inserts, devices for application of eye drugs, devices for healing eye injuries and the like. The cyclic portion of the lens production process generally involves metering a liquid crosslinkable and / or polymerizable material into a female mold half, coupling one half of the male mold to the female mold half, irradiate to crosslink and / or polymerize, separate the mold halves and remove the lens, clean the mold halves, and advance the mold halves to a dosing position. The process can use a variety of polymerizable and / or crosslinkable materials. However, it is preferred that the polymerizable and / or crosslinkable materials can be polymerized and / or crosslinked in a short time, i.e., within the cycle time of one or two steps of the process, for example, in less than one minute, more preferably in less than 30 seconds, and still more preferably in less than 10 seconds. A preferred class of crosslinkable and / or polymerizable materials is described more fully herein. For convenience, the terms "prepolymer" and "polymer precursor" will be used in the present of a interchangeably, to describe the crosslinkable and / or polymerizable materials. The partially cyclic, semi-continuous molding processes of the present invention take advantage of the reutilization or recycling of the mold halves used to retain the liquid prepolymer material and give the molded articles their shape. In one embodiment, the mold halves are used at least 1,000 times, that is, each pair of mold halves produces at least 1,000 molded articles before being discarded or restored. Preferably, the mold halves are reused at least 10,000 times, more preferably at least 100,000 times, and still more preferably the mold halves are reused at least 1,000,000 times. The reuse of the molds, or at least one mold half, offers a number of advantages over the prior art processes, wherein the plastic molds are discarded after one use. One advantage of the reuse of the mold half, is that the amount of mold halves that are discarded or recycled is reduced in a remarkable way. This can reduce the costs of manufacturing molded articles, which reduces the price charged to the customer for the molded article. Also, the use of reusable mold halves, instead of using single-use mold halves, reduces the final waste imposed on the environment, which should always be a goal of manufacturing operations. In addition, the halves Single-use mold patterns offer more opportunities for inconsistencies of the molded article, merely because each molded article requires two new mold halves, each of which may contain one or more defects. Yet another advantage is that the reusable mold halves eliminate the need for mechanisms that feed, orient, and store the multitude of single-use mold halves required for that production process. Each of these mechanisms is costly by itself, and each mechanism can fail in an independent way, thus reducing the overall production of the process. Yet another advantage of the reusable mold halves is that mold halves of extremely high quality can be used, and the higher mold quality is generally translated into finished lens products of higher quality. Yet another advantage is that the use of the same mold halves repeatedly ensures the consistency and reproducibility of the molded product. Accordingly, the advantages of reusable molded articles in a partially cyclic, semi-continuous process are numerous. It should be noted that the innovative cyclic portion of the lens production process does not require the reuse of both mold halves, although this is a preferred embodiment. For example, the repeated use of a series of male mold halves in conjunction with disposable female mold halves offers certain advantages. An advantage of this mold process reusable / disposable, is that the female mold halves can be adapted to be used both as a female surface molding instrument and as a portion of the final lens package. In this embodiment, a portion of the lens packaging process can be eliminated, i.e., the portion related to the production of packages for retaining contact lenses. Other innovative aspects of the molding processes will be described more fully with respect to a preferred embodiment of the overall process described hereinafter.

A ^ MOLDING PROCESSES A preferred embodiment of the invention, shown schematically in Figure 1, is a process for the fabrication of a molded article, especially a contact lens, which includes the following steps: (a) dosing the liquid prepolymer in one half or in mold halves, preferably in a plurality of female mold halves; (b) closing the mold (s), for example, by coupling the male mold half with the female mold half (or the plurality thereof), - (c) crosslinking and / or polymerizing the prepolymer material to form a solid molded article; ~~ (d) inspect the central region of the molded item (s); (e) opening the mold (s), for example, by separating the male mold half from the female mold half; (f) removing the unreacted prepolymer from the mold (s) and from the molded article (s); (g) applying water to the female mold half to facilitate centering of the molded article (s), which may already be located on the female mold halves, or subsequently can transfer from the male mold half; (h) transferring any molded article (s) on half or half mold halves to half or half of female mold halves (or vice versa), - (i) centering the molded article (s) (s) on the half or the mold halves (this is optionally done in a passive manner); (j) removing the molded article (s) for packaging; (k) inspecting the periphery of the molded article (s); (1) clean the mold (s); and (m) advancing the mold (s) to a position for the prepolymer dosage. It must be observed from the beginning, that the order Some of the steps are not highly critical. For example, although the prepolymer dosage, the closure of the molds, and the crosslinking must be presented in a sequential order, the inspection steps can be presented in a variety of locations throughout the entire process. In addition, some of the steps are optional in the broader aspects of the invention, such as inspection, centering, or transfer. In addition, some of the steps or steps of the process, such as the peripheral inspection and body stages, can be combined in one step. The cycle times for the steps may vary, depending on a number of factors, such as the specific polymer composition and the dimensions of the molded article. Clearly, it is preferred to minimize cycle times in order to maximize production speeds. Preferably, the individual cycle times are less than about 1 minute each, more preferably less than about 30 seconds, still more preferably less than about 10 seconds, and most preferably less than about 6 seconds. In a preferred embodiment, a final molded product can be formed from the initial prepolymer material, inspected and separated from the mold in a period of less than about 20 minutes, more preferably less than about 10 minutes, still more preferably less than about 2 minutes, and very preferably less than about 1 minute. The molds used to form the ophthalmic lenses are preferably two-sided molds, that is, the complete mold includes a male mold half (convex or base curve) and a female mold half (concave or front curve). However, different embodiments of the invention can be used with other types of molds. 1. Molding Tool The semi-continuous, partially cyclic molding process can be operated with a single mold that is cycled through the process. However, in a preferred embodiment, the process uses a plurality of molds configured and aligned in a molding tool, in order to improve the efficiency of the process. For example, Figure 2A illustrates a plan view of one embodiment of a molding tool 20 having an array of 10 complete molds. The molding tool 20 includes an array of 10 female mold halves 22 removably positioned in a first housing 24. The molding tool 20 further includes an array of 10 male mold halves 26 positioned in a removable manner in one second housing 28. The first housing 24 is fixed to the second housing 28 by a pivoting element 30, which allows the second housing 28 to articulate towards the first housing 24, in order to couple in a releasable manner the male and female mold halves. Accordingly, the first housing 24 is hingedly fixed to the second housing 28. In the operation, liquid prepolymer (or a solution or dispersion thereof) is dosed into the female mold halves 22. The male mold halves 26 are coupled with the female mold halves 22 rotating and linearly moving the second housing 28, as shown by the arrow in Figure 2B. The molding tool 20 is shown in a closed position (ie molding position) in Figure 2C. In Figure 2C, the ten pairs of mold halves are coupled, thereby defining ten molding cavities 32 in which a lens can be formed. The mold halves can be formed from a number of materials, at least one of which transmits the desired radiation for crosslinking and / or polymerization, preferably on the ultraviolet scale. A preferred material that can be used for reusable molds is quartz. The reusable mold half is preferably the male mold half. Preferably, only one mold half transmits enough radiation, while the other half does not. The quartz offers substantial advantages in durability, thus allowing the molds to be reused a significant number of times without affecting the quality of the product. However, quartz molds are very expensive. In an alternative way, the mold halves can be molded from a polymeric material, at least one of which transmits the desired radiation. Examples of suitable mold materials include polystyrene, polypropylene, and poly (acrylonitriles), such as BAREX. In a preferred embodiment, the mold halves of at least one of the set of male mold halves, or of the set of female mold halves, include a peripheral region that blocks light (especially ultraviolet light) during polymerization and / or the cross-linking The use of this periphery that blocks light, makes possible a precise definition of the edge of the lenses that are formed. This region can be produced by depositing a metal coating in the region outside the lens-forming surfaces of the mold halves. 2. Dosing of the Prepolymer During the dosing step, the prepolymer (for example, crosslinkable polyvinyl alcohol polymer precursor solution) is dosed in a plurality of female molds, which can be configured in rows (for example, two rows of five each, as shown in Figure 2A). The dosing conditions of the prepolymer can have a significant impact on the quality of the final molded lens. Therefore, the humidity conditions of the dosage, the leveling from the dosing tip to the bottom of the female mold surface, and the distance from the dosing tip to the side of the female mold surface, to minimize defects. Figure 3 shows a preferred prepolymer dosage configuration 40. Metering element 42 (eg, a syringe or metering needle) includes a tip portion 44 through which the prepolymer passes to fill the female mold half 46 The tip portion 44 is positioned above the female mold half 46 at a distance "b" from the bottom surface 48, and at a distance "a" from the central axis 50 of the mold. The dispensing tip preferably is (1) within a certain distance "a" from the center axis of the mold (off-axis), and (2) within about 1 to 3 millimeters from the female mold half. Preferably, the dosing element 42 is in contact with the dosed liquid contained in the female mold after finishing the dosing (ie, touching the surface of the prepolymer) to prevent harmful bubbles from forming. Air bubbles, depending on their location, can cause defects in the final lens product. Defects can impair structural integrity, thereby resulting in tears, or more commonly, defects can cause optical imperfections that impair the consumer's vision. It is important to note that bubbles are often formed, but if the bubble is localized sufficiently close to the edge, it can be removed (ie, "squeezed out") during the step of coupling the male mold half with the female mold half. Moreover, it is preferred to overdose or overfill the female mold half, in order to minimize the defects, especially those related to shore problems. In a preferred embodiment, the distance "a" from the central axis of the mold 50 is from about 3 to about 7 millimeters. More preferably, the distance "a" is from about 5 to about 6 millimeters. In a preferred embodiment, the distance "b" from the portion of the dosing tip 44 to the bottom surface of the mold 48 is from about 0.1 to about 4 millimeters. More preferably, the distance "b" is from about 1 to about 3 millimeters, while still more preferably, the distance is from about 1.5 to about 2.5 millimeters. Keeping the distance "b" so small prevents the droplets or the liquid stream from being dosed at a sufficient height to generate bubbles, which can result in defects. High humidity is preferred during the dosing step, in order to prevent the formation of a surface film or "skin", and / or the generation of bubbles during the filling process. Relatively high humidity inhibits drying and dehydration of the prepolymer solution in the dosing tip. Preferably, the relative humidity surrounding the prepolymer during dosing is about 55 percent or greater. More preferably, a relative humidity of about 60 to about 80 percent is maintained during dosing. In addition, a high humidity helps to avoid Schlieren optical defects in the lenses. Another factor related to the dosing step of the prepolymer solution, which must be selected with care, is the diameter of the dosing tip. A diameter that is too small or too large can cause bubbles to be generated. A preferred diameter of the metering tip is from about 0.5 millimeters to about 4.0 millimeters, more preferably from about 0.5 millimeters to about 2.0 millimeters, and still more preferably from about 1 to about 1.5 millimeters. A "skin" can form on the surface, if it takes too long before molding, especially if the humidity is low, due to dehydration. According to the above, the time from the final dosage of the prepolymer to the closure of the molds should be minimized. Preferably, the time from dosing to closure of the mold is less than about 30 seconds, more preferably less than about 15 seconds, and still more preferably less than about 8 seconds. 3. Mold Closure The molding assembly is preferably closed immediately, subsequent to the prepolymer dosing step. The male mold housing is preferably joined by a pivot element or articulation element to the female mold housing. The closing of the molds preferably takes place in a two-step movement, which includes: (1) angularly articulating one mold housing towards the other mold housing, followed by (2) moving one mold housing towards the other (or moving both mold housings towards each other) in a substantially linear motion, while the mold surfaces remain substantially parallel to one another. Accordingly, in one embodiment, closing the molds by turning the first or pivoting the housing male mold (and arrangement removably fixed halves male mold) around the hinge member, to a position of engagement with the housing of corresponding female mold (and the removably fixed arrangement of the female mold halves). The angle of rotation depends on the desired resting position of the male mold housing relative to the female mold housing, prior to the step of closing the mold. Preferably, the angle of rotation is from about 90 to about 270 degrees (preferably from about 150 ° to 210 °, and more preferably from about 170 ° to 190 °).

The first movement, that is to say the angular articulation, preferably occurs at a relatively fast speed, while the second movement, that is, the linear movement, occurs relatively slowly. The angular joint preferably occurs in less than 1 second (for example, at a rate of about 100 ° -500 ° / second, more preferably about 200 ° -300 ° / second). The linear movement may occur at a rate which does not cause substantial defects or lost process time, for example, at a rate of about 0.1 to 2 mm / second, and preferably about 0.5 to 1 mm / second. It is preferable to minimize the linear movement, in such a way that the speed of the overall process is maximized. Accordingly, the linear distance of preference is presented over a distance of less than 6 millimeters, more preferably of about 1 to 3 millimeters. Although it is generally preferred to minimize the time required to close the molds, excessive coupling speeds of the mold halves can cause defects. Excessive coupling speeds can cause bubbles to form, or they can inhibit the escape of bubbles already present in the pre-polymer solution. However, this angular articulation speed depends a little on the location of the mold halves in relation to the articulation element, which fixes the housing. cough mold male and female each other. Normally, all mold halves are placed less than about 25 centimeters from the hinge element. In this case, the angular joint speeds described above are normally acceptable. It should be noted that an outstanding feature that must be considered in the establishment of angular joint velocity is the production of a high quality product. According to the above, although speeds revolute joint mentioned herein are good guides, the angular velocity of joint used in a configuration particular tool may be selected to minimize defects lens, and secondly, to maximize the volumes of production. As mentioned above, it is desirable to minimize the time required for closure of the mold, because it is desirable to minimize processing times in any manufacturing steps. According to the above, angular articulation speeds can be maximized in regions where lens defects are not generated by high articulation speeds. In a preferred embodiment, a mechanical mechanism is used in the final closing movement, in order to ensure a reduced rotation speed. Another aspect of the mold closing process that can affect the index of defects formed in the lenses is related to whether all mold halves substantially experience the same mold closing conditions. It is highly preferable to close all the molds in a substantially simultaneous manner, and at a substantially equal speed. If all the molds are closed at the same time, all the finished products will have experienced the same time delay from the closing of the mold to the step of polymerization and / or crosslinking. The uniformity of mold closing speeds and times improves the quality and consistency of the product. Accordingly, it is highly preferred to bring the mold housings to a position where the molding faces are substantially parallel to each other, before the final linear movement is effected. 4. Initiation of the Cross-linking and / or Polymerization. Subsequent to the mold closing step, polymerization and / or crosslinking is initiated, thereby transforming the liquid prepolymer into a solid form, the shape being determined by the mold halves. Preferably, the molding tool is advanced to another stage, where a form of radiation is hit on the molds, which allows substantially all the radiation to be transmitted through them, and therefore makes contact with the prepolymer liquid. The preferred wavelengths of radiation are on the ultraviolet (UV) scale. The irradiation period of preference is less than about 5 minutes, more preferably less than about 1 minute, and still more preferably less than about 10 seconds. Preferably, the irradiation is carried out in a step or stage of the process, but this is not a requirement, because more than one stage of the process can be used for irradiation. For example, if a uniform step duration of approximately 4 seconds is selected for the process, but an irradiation time of about 6 seconds is desired, two irradiation steps can be inserted into the process, to provide adequate irradiation. The period of irradiation required is a function of the intensity of the applied radiation, the selected prepolymer, and the particular photoinitiator used. A preferred intensity of ultraviolet radiation for the polyvinyl alcohol prepolymers is from about 1 to 5 milli-watts per square centimeter, more preferably from about 2 to about 3.5 mW / cm2, and still more preferably from about 2.8 to 3.2 mW. / cm2. A preferred wavelength of applied radiation is from about 280 to about 380 nanometers, more preferably from about 305 to about 350 nanometers. The peak wavelength of the radiation source is preferably not within the applied wavelength scale, in order to avoid brittle lenses being formed. It is preferred to use a filter to achieve the desired applied wavelength scale, with the so as to avoid this problem of the lens being brittle. A preferred method for applying radiation involves using an element to mask the radiation in the areas outside the lens-forming cavity, thereby defining the edge of the lens with the masking element. The advantages of this mode are that the contour of the bank can be controlled in a precise and exact manner, edge defects are minimized, and subsequent shore processing is not required. In addition, the molds are preferably kept spaced apart from each other in such a way that a thin annular gap is formed along the periphery, which allows a path for the excess prepolymer to escape. U.S. Patent Application Number 08 / 274,942 (Hagmann et al.) Teaches some configurations and designs of preferred mold halves, as well as preferred methods of radiation application, and teachings thereof are incorporated herein. as reference.

. Internal Lens Body Inspection Subsequent to polymerization and / or crosslinking, the lens product can be automatically inspected at any of a number of stages of the molding and / or packaging processes. Although it is preferred to inspect the entire lens in one stage, it is not always practical, because, among other Things, the inspection methods of a stage suffer from image interference by the lens support element. Also, although there are stages where the entire lens can be inspected without substantial support interference, the stage may be early enough in the process that another inspection before packing is required. Accordingly, in a preferred embodiment, a central area of the lens is inspected in one step, while the periphery or edge of the lens is subsequently inspected, or vice versa. In a more preferred embodiment, shown in Figure 1, the body of the lens is inspected in a step immediately subsequent to the irradiation step. A preferred method of inspecting the lens body is to use an inspection camera and an associated light source for each row of lenses in the molding tool. A preferred lighting technique is bright field illumination, where defects appear dark, while acceptable regions appear clear. For example, Figure 4 shows a perspective view of a lens body inspection system 60 that includes a pair of detectors 62 and 64 (e.g., cameras, such as a CCD camera) positioned above the lenses. Ten stationary light sources 66 are placed under the lenses. Each detector inspects five lenses in sequence in this modality. In operation, the light shines from the light sources 66, and simultaneously through the molding cavities 70 and 72, and impacts the detectors 62 and 64. The detectors 62 and 64 each generate a signal, for example, a digital image of the lens, which is transmitted to the computer 74. After the inspection of the two is performed First lenses, detectors 62 and 64 advance forward (shown by the arrow in Figure 4) to inspect the next two lenses. The computer 74 compares the signals generated with one or more threshold signals or criteria, in order to determine whether the lens is of acceptable quality. The lens is packaged or discarded at a subsequent stage or stages, based on a signal output from the computer to a downstream controller. 6. Mold Opening Subsequent to the polymerization and / or crosslinking step, and preferably subsequent to the inspection step of the central body, the molds are opened as shown in Figures 5A and 5B. The male mold housing 80 preferably first moves linearly away, and then articulates away from the female mold housing 82, in order to open the molds. The linear movement of preference is presented relatively slowly at the beginning, as shown in Figure 5A, in order to separate the male mold halves 84 from the female mold halves 86, resting the lens on one of the halves printed. As it is shown in Figure 5B, the slow linear movement during the passage of the separation of the mold halves, is followed by a relatively rapid articulation of the male mold housing 80, to a fully open position on the remaining radius r (eg, 180 ° ) as shown in Figure 5B. The separation step of the mold half occurs at a relatively slow speed, in order to minimize optical defects, for example, Schlieren optical defects or scratches. The Schlieren optical defects are essentially folds in the lens. It is believed that Schlieren defects occur when the opening speed of the mold housing occurs too fast. Stretching or pull of the lens only occurs when both molds are in contact with a corresponding surface of the lens, in such a way that the slower initial speed of the linear movement only needs to occur until at least one of the mold halves is separated from the lens. The articulation of the male mold housing can be realized by any number of elements known in this field. For example, two or more electric motors can be used to articulate the male mold housing at two or more speeds. Alternatively, an electric motor with a variable speed controller can be used to control articulation speeds. In a preferred embodiment, a mechanical mechanism is operated (for example, an engine electric) to slowly separate the molds, and then an electronic motor and a drive mechanism are operated, to articulate the male mold housing quickly after the mold separation. The drive of the articulation element can also be presented by any number of elements known in this field, ie, electronic, mechanical, optical, or any combination thereof. The control of articulation speeds can be controlled precisely by a local programmable logic controller, or by a central computer that controls the movements of many or all steps of the process. 7. Cleaning the Half of the Mold Once the mold halves are separated, the unreacted prepolymer can be removed by applying solvent, preferably water, to the mold surfaces and to the lenses. Figure 6 illustrates a sectional view of a preferred configuration for cleaning after molding 90.

Water 92 is dosed on the surfaces of the mold, from a plurality of nozzles 94 positioned around the periphery of the edges of the mold. A variety of water metering nozzles, or a blade edge type metering nozzle could be used to properly dose water.

The dosed water and any unreacted prepolymer are removed by a vacuum tube 96 placed directly above the surface of the mold. Normally, the lens still adheres to the male mold half, such that Figure 6 does not illustrate a lens that rests on the female mold half. However, sometimes, the lens can remain on the female mold half after the separation of the mold halves. In addition, the application of air currents may be convenient. For example, a plurality of air nozzles may be placed around the periphery of the mold, preferably placed between two water nozzles. Applying drafts, along with water currents, can help disperse water through the mold. In addition, the lens can be maintained in a better position by appropriate adjustment of the impact angle on the surface of the lens, and of the flow velocity of the applied air. Clearly, a number of cleaning configurations can be provided, which would be within the scope of the invention. For example, the vacuum pipes and the water dosing nozzles can be commutated, so that water is dosed in the central area, while an effluent vacuum is applied to the periphery of the molding surface. According to the above, the invention is not limited to the particular configuration of cleaning components after molding, as disclosed in Figure 6. 8. Wetting of the Female Mold Half Subsequent to the cleaning step, preferably a liquid, for example, water or a saline solution, is applied to the female mold surfaces. Although this step is optional, a drop or a few drops of water may be added to the mold halves, in order to lubricate the lenses, to enable the lenses to center on the female mold halves. The centering of the lenses in the female mold halves is desirable for the actions that are presented in the subsequent steps. In particular, it is desirable to keep the lens in a consistent location within the female mold half during one or more subsequent inspection steps. Furthermore, it is preferable to have the lenses located in a consis- tent place in the female mold halves, in order to ensure that the location of the lenses on the removal arm is consistent and predictable, for inspection and / or transfer. from the lenses to the packaging. Although the lenses are preferably molded from a material that does not require subsequent hydration, the vacuum applied during the cleaning step can dehydrate the lenses to some degree. According to the above, another advantage of adding water to the female mold half, can be to avoid dehydration. Therefore, centering the lens inside the Female mold half can be made by dosing a liquid to the lens in a first stage, and advancing the lens to a second stage, thereby providing the lens with sufficient lubrication and time to center the lens inside the mold half female. Although the liquid can be dosed in the center of the mold half, in one embodiment, the liquid is applied along the periphery of the female mold half, to better ensure that the entire surface is wetted. Although the volume of dosed liquid is not generally critical, it is usually dosed from about 0.01 to about 5.0 milliliters (preferably about 0.05 to 0.20 milliliters) over the female mold half. It should be noted that the previous wash step can be combined with the centering step. In other words, the application of an aqueous solution for washing the unreacted prepolymer of the lens and / or the mold halves, can simultaneously loosen the adhesion of the lens to the half of the mold. Accordingly, in order to achieve washing and unlocking (i.e., lens-mold separation), dosing pressure, dosing nozzle location, and "nozzle-to-lens" angle in a single step, they must be selected for the purpose of simultaneously removing the unreacted prepolymer and effecting separation of the lens-mold In addition, the lens may or may not be on the female mold half at this stage (i.e., after separation of the mold). the mold halves). Accordingly, the lens may be resting on the male mold half, or on the female mold half. If the lens is not on the female mold half, which is normally the case, and the female mold half is substantially dry, it is still desirable to moisten the female mold half. This wetting inhibits the adhesion of the lens, and promotes lens centering, when the lens is subsequently transferred from the male mold half to the female mold half. As mentioned above, the mold masking methods of European Patent Application Number 637,490 (Priority Application of the Application of the United States of America No. 08 / 274,942), are a preferred molding method according to the present invention. . In a preferred embodiment of this method, the radiation is prevented from impacting the areas that are outside the molding surfaces of the molds, with a metal mask (for example, a coating of chromium in the area of the non-reflecting surfaces). molded). In order to prevent damage (eg, dissolution) of this metal mask, preferably the applied water (both the washing liquid and centering agent) has at least a conductivity greater than about 100 micro-Siemens, more preferably greater than , or equal to, approximately 150 micro-Siemens. 9. Transfer of the Lens From the Male Mold to the Moldé Female. Before transferring the lenses to the package from the molds, you must know the exact location of all the lenses. Each lens may have adhered to the male mold half or to the female mold half. Normally, the lens will adhere to the male mold half. In addition, one or more surfaces of lens mold halves can be treated, for example, by plasma coating, to increase or decrease the adhesion force between the lens and the selected mold half, thereby increasing the likelihood that a lens is located in the selected mold half. In order to ensure that all lenses are located in the female mold half, a step of transferring the lenses from the male mold halves to the female mold halves in the process can be included. Figures 7A-C illustrate side sectional views of a preferred automatic process for transferring any lenses that are over the male mold halves to the female mold halves. In Figure 7A, the robotic arm 102, which is positioned above the male mold half 106, holds the lens 104, and removes the lens 104 from the male mold half 106 on which it rests. The robotic arm 102 is preferably equipped with a vacuum line, and with a valve that can be electronically controlled, in order to effect the clamping and the subsequent lens release. Figure 7B shows the rotation of the first robotic arm 102 to a position directly opposite the second robotic arm 108. The lens 104 is transferred to the second robotic arm 108, which is generally positioned above the female mold half 110, when the robot is closed. vacuum valve on the first robotic arm 102, and opens almost simultaneously on the second robotic arm 108. In Figure 7C, the second robotic arm 108 rotates downwards, as shown by the arrow, to align the lens 104 with the female mold half 110. Once the lens and mold half are aligned, the vacuum valve is closed, thereby allowing the lens 104 to be released into the female mold half 110. Preferably, this step is performed on all male molds, regardless of whether there are lenses on the mold or not. In the vast majority of cases, the female mold half will not contain a lens. However, by uniformly applying the passage to all male mold halves, the process ensures that all lenses are located in the female mold halves. Clearly, a number of variations of the transfer process described above can be foreseen. For example, it may be preferable to apply a positive pressure when the lens is released, instead of merely discontinuing the vacuum.

Positive pressure would ensure that the lens does not adhere to the robotic arm due to purely hydrostatic forces or other forces. A variety of other lens transfer systems are within the scope of the invention.

. Optional Rest Position After any step of the process, the tool can advance to a rest position, in order to provide the process with an intermediate zone of one or more tools. This configuration can be convenient for making tool changes, that is, providing one or more positions where the tools can be easily removed, and can be replaced with tools that hold the molds with a new optical power. Although theoretically one or more rest positions can be inserted between any two steps, certain positions may be more convenient than others. For example, although the insertion of a resting position immediately subsequent to the prepolymer dosage step is within the scope of the invention, it would not generally be desirable. Subsequent to dosing the prepolymer, it is preferred to proceed immediately to the crosslinking and / or polymerization step, thereby eliminating any potential defects associated with the delay (eg, dehydration of the prepolymer). 11. Centering of the lens. As mentioned above, the application of an aqueous solution, especially deionized water, is preferably applied to the female mold halves, in order to lubricate the lenses and the surfaces of the mold half, thus promoting the centering of the mold. the lenses in the female mold halves. This consistent focusing of the lenses reduces the problems associated with the inspection downstream of the lenses, and the transfer of the lenses to the package. Although the application of an aqueous solution to the female mold surface lubricates the lens and the mold surface of the female mold half, something more is usually required to promote centering of the lens in the female mold half. In particular, some movement of the female mold half and some time of delay before further processing is preferred, subsequent to the application of the aqueous solution, in order to allow the forces of gravity to cause the lens to focus on the half of female mold. In a preferred embodiment, a centering station is provided wherein operations on the lens and the female mold half are not performed while the lens is centered. The mere movement of the conveyor, which moves the lens and the female mold half to and from the centering station, is normally sufficient to enable the lens to center itself within the female mold half. However, you can it is preferable to apply a form of energy (e.g., a slight vibration or oscillation) to the female mold halves containing lenses during the centering step. Regardless of the technique employed, some elements are desirable to ensure that the lenses are centered inside the female mold halves. 12. Lens Removal and Water Droplet Removal Lenses can be removed from the female mold halves for inspection and / or packaging, subsequent to the transfer step from male to female (9) by any of a number of known means in this. countryside. Robotic transfer arms, with vacuum lines and controllable valves, analogous to those used in the lens transfer process, can be used to remove the lenses from the female mold halves. Prior to the inspection of the lenses, the surface water droplets are preferably removed. Droplets of water on the lenses can cause optical distortion, which will cause the lenses to be inadvertently selected for rejection during the shore inspection process. Accordingly, a slight air current is preferably applied to the lenses while the lenses are being held by the robotic transfer arms. However, the lens can be dehydrated by the application of excessive amounts of air, or air whose humidity is too low. In a plan view, the edge of the hydrated lens is circular. Unfortunately, even a slight dehydration will change the shape of the lens, thus distorting the edge of the lens from circular in a plan view, and damaging the automatic inspection of the edge of the lens. Accordingly, wet air is preferably blown onto the lenses to remove adhering water droplets without dehydrating the lens. The humidity of the air is preferably about 40 percent relative humidity or higher, more preferably about 60 to 80 percent relative humidity. 13. Inspection of the edge of the lens. As mentioned above, a preferred embodiment involves inspecting the periphery of the lens while the lens is centrally stopped by a robotic arm (e.g., by vacuum). Figure 8 illustrates a preferred shore inspection system 110, wherein a lens 112 is stopped by a robotic arm 114, while inspection is presented. The robotic arm 114 advances downward to a position where the peripheral light source 116 can properly illuminate the edge of the lens 112. The detector 118, e.g., a digital camera, is placed under the lens 112 and the light source. 116. An image or images generated by the camera 118, are sent to computer 120 for a determination of whether the edge of the lens meets the quality specifications. In detail, a preferred method of peripheral inspection works as follows. The light source 116 (eg, a fiber optic ring light) is selected and positioned in such a way that the edge of the lens is illuminated with the light beam striking at an angle of incidence. The camera 118 sees the lens 112 through the light source 116. The edge of the lens disperses some of the incident light into the opening of the camera. Consequently, the image appears clear against a dark background. Two cameras are used that advance 5 times for the 10 lenses. During the inspection procedure, it is convenient to keep the lenses in a substantially stationary position. In a preferred embodiment, shown in Figure 8, the lens is centrally stabilized by the robotic arm 114. In addition, the periphery of the lens is stabilized in the embodiment of Figure 8 by the stabilization arms 115. - The lens can be rejected immediately subsequent to inspection, for example, by releasing the vacuum on the robotic arm, and allowing the lens to fall into a waste tray. Alternatively, defective lenses can be rejected at a current point down. For example, defective lenses can be released and discard immediately before dosing the lens to a final package. However, preferably, defective lenses are released in a station subsequent to the station to dose good quality lenses to a final package. An advantage of the latest techniques is that, at this point, all lens debris can be coordinated and performed, including lenses that were previously rejected by defects of the central lens body. Figure 8 illustrates the inspection of a single lens. The entire array of lenses (for example, two columns of five rows) can be inspected by a series of cameras and lighting arrangements, with one camera and light source per lens. However, a more efficient process involves the use of a camera and light source for each lens column. Accordingly, two cameras, placed under the lens array, can advance through the two lens columns. The robotic arm with the lens (from above) advances downward when the camera has advanced to the position under the lens. In this way, a smaller number of the more expensive components, ie, the cameras, is required for the process. 14. Transfer of Lens to Packing / Disposal of Trash Lenses that are selected for re-casting from the previous stages of peripheral or central inspection, can be simultaneously discard immediately before, or preferably subsequently, the packaging of high quality lenses. This can be done through the use of a database that stores and disseminates the locations of the lenses selected for disposal by the previous body and shore inspection processes. A preferred method of carrying out this process involves first moving the robotic arms that stop the lenses, subsequent to inspection of the edge, to a station above a conveyor that retains a series of individual contact lens packages. A computer that has stored the location of the unacceptable lenses, relieves a signal to the protractor, to advance forward, and place an individual contact lens package under the lens, if it was determined that the lens is of acceptable quality. However, if the lens was selected for rejection, either by edge or body defects, the computer does not point to the protractor to advance an individual contact lens pack forward. Regardless of whether the computer generates a conveyor advance signal, the computer subsequently generates a signal that causes the lens to be released from the robotic arm (for example, by closing the vacuum valve). If the packaging conveyor has advanced forward, the lens falls into a package for subsequent distribution.

In a preferred embodiment, lenses of poor quality can be discarded at a stage prior to the packaging stage. This mode provides a junk tray location spatially separated from the packaging conveyor, which offers advantages in access to both the reject and packaging stages. Although a number of control systems can be provided for the rejection of poor quality lenses, there are advantages in discarding all lenses of poor quality in one place. For example, this process requires only one place for garbage and waste collection, thus minimizing the number of garbage containers and the consumption of space associated with it. However, the invention is not limited to the selected location for discarding lenses of poor quality.

. Dosage of Saline Solution and Sealing of the Packaging After the contact lens has been placed in the individual lens package, saline can be added to the package. Alternatively, saline can be added to the lens package before the lens is released into the package. If the preferred prepolymer (see below) is crosslinked to form the lens, a relatively high pH salt solution in the package is desired. A preferred pH from about 7 to about 9. The relatively high pH salt solution is used to terminate the hydrolysis of the groups on the preferred polyvinyl alcohol base structure. Preferably, the pH is reduced during autoclaving, subsequent to sealing the package, to a physiologically acceptable pH. Once the saline and lens have been added to the package, a seal can be releasably secured to the package. Preferably, a polymer sheet or film, or a combination thereof, is applied to the package, such as the removable seal. The sealant film can be releasably secured to the package by means of a number of methods, such as heat sealing, pressure sealing, or application of any of a number of adhesives. A preferred contact lens package is disclosed in U.S. Patent No. 5,409,104, assigned to Ciba-Geigy Corporation, which is incorporated herein by reference. 16. Mold Cleaning and Drying After the lenses are removed from the molding tool, the molding tool is advanced to a tool cleaning step. The molding tool can be washed with water currents at a relatively high pressure in this stage, because there are no lenses present. two to pack, that is, the only lenses that remain on the mold halves at this stage are garbage. First, the molding tool is completely washed to remove any debris, such as strongly adhering portions of lenses, or any other undesirable material. Then, the molding tool is dried, preferably by the application of air currents, while simultaneously applying a slight subatmospheric pressure to remove the dislodged water. In a preferred system, jets of air are formed around the periphery of each mold half, both male and female. A vacuum effluent tube is placed over the center of each mold half, to remove the discharged water droplets. Alternatively, the air jets can be applied centrally, while a peripheral vacuum removes the water. In addition, the vacuum effluent can be omitted if the air currents are properly adjusted. After the molding tool is completely washed and dried, the tool is preferably advanced to the prepolymer dosing position, ready for another production cycle. 17. Cyclic Series of Process Steps One particularly convenient and novel aspect of many embodiments of the present ophthalmic lens manufacturing process is that one or more series of process steps They are cyclical. In contrast to the typical molded lens manufacturing process, where the lenses are produced by means of a set of linear process steps using single-use disposable plastic molds, the present processes offer advantages in the consistency of the process and the product, and in the consumption of material and reduced time, through the use of one or more cyclic processes. Preferably, the lenses are manufactured by a series of two or more cyclic processes. In a preferred embodiment, the lenses are manufactured by a first repeat cycle that includes the steps of dispensing liquid prepolymer into a reusable mold, including male and female mold halves, forming the lens, and separating the mold halves. This preferred embodiment also includes a second cycle of repetition, wherein the lens is removed and transferred to a packaging process. At least one of the repetition cycles preferably includes a step of inspecting the lenses. In a preferred embodiment, the lenses are inspected in a central region in the first repetition cycle, while inspecting a peripheral region or regions in the second repetition cycle. Figure 9 illustrates a preferred embodiment, wherein the lens manufacturing process includes two cyclic processes. The first cyclic process begins with the dosing of the prepolymer in the female mold halves, followed by the steps of: coupling (i.e., closing) the male and female mold halves, forming the lenses (e.g., by applying ultraviolet radiation), inspecting the lenses, separating the mold halves, loosening the lenses and washing the prepolymer unreacted from the lenses, moisten the female mold halves, transfer any lenses that are over the male mold halves to the female mold halves, and clean the mold halves. After the mold halves are cleaned, the mold halves are advanced to the prepolymer dosage step once more. In the embodiment of Figure 9, subsequent to the lens centering stage, the lenses are clamped and removed in the second series of cyclic process steps. The attachment and removal of the lens is followed by the inspection of the lens, the deposit of high-quality lenses in the packaging, and the disposal of unacceptable lenses. It should be noted that a person having ordinary experience in this field can foresee a wide variety of cyclic configurations of process steps, given the extensive disclosure contained herein. In accordance with the Accordingly, the broader scope of the invention is not limited to the specific configuration of process steps disclosed hereinbefore.

B. PREFERRED PREPOLIMER MATERIALS The invention is not limited to a particular crosslinkable and / or polymerizable material, also referred to herein as a prepolymer. However, certain prepolymers are preferred according to the preferred embodiments of the invention. Preferred prepolymers for use in the process according to the invention are those which are soluble in water, and which comprise crosslinkable groups. In particular, preferred prepolymers include those described in U.S. Patent No. 5,508,317, issued to Beat Müller on April 16, 1996, and assigned to Ciba-Geigy Corporation. U.S. Patent Number 5,508,317 is hereby incorporated by reference in its entirety. A preferred group of prepolymers, as described in U.S. Patent No. 5,508,317, are those that comprise a basic structure of 1,3-diol, wherein a certain percentage of the 1,3-diol units has been modified. diol up to a 1,3-dioxane having, in position 2, a radical which can be polymerized, but which is not polymerized. The polymerizable radical is especially a radical of aminoalkyl having a polymerizable group bonded to the nitrogen atom. The prepolymer is preferably a derivative of a polyvinyl alcohol having a weight-average molecular weight, Mw, of at least about 2,000 which, based on the number of hydroxyl groups of the polyvinyl alcohol, comprises from about 0.5 to about 80% by weight. one hundred units of formula I: where : R is lower alkylene having up to 8 carbon atoms, R1 is hydrogen or lower alkyl, and R2 is an olefinically unsaturated copolymerizable electron attracting radical, preferably having up to 25 carbon atoms. R2 is, for example, an olefinically unsaturated acyl radical of the formula R3-C0-, wherein: R3 is an olefinically unsaturated copolymerizable radical having from 2 to 24 carbon atoms, preferably from 2 to 8 carbon atoms, in a particularly preferred way of 2 to 4 carbon atoms. In another embodiment, the radical R2 is a radical of the formula II: • CO-NH- (R 4 -NH-CO-0) q-R 5-0 -CO-R 3 di: wherein: q is zero or one, and R 4 and R 5 are each independently lower alkylene having from 2 to 8 carbon atoms, arylene having from 6 to 12 carbon atoms, a saturated divalent cycloaliphatic group having from 6 to 10 carbon atoms, arylenenalkylene or alkylenearylene having from 7 to 14 carbon atoms, or arylenenalkylenearylene having from 13 carbon atoms; to 16 carbon atoms, and R3 is as defined above. Accordingly, the preferred prepolymer is especially a derivative of a polyvinyl alcohol having a molecular weight of at least about 2,000 which, based on the number of hydroxyl groups of the polyvinyl alcohol, comprises from about 0.5 to about 80 percent units of formula III: wherein: R is lower alkylene, R1 is hydrogen or lower alkyl, p is zero or one, q is zero or one, R3 is an olefinically unsaturated copolymerizable radical having from 2 to 8 carbon atoms, and R4 and R5 are each one independently lower alkylene having from 2 to 8 carbon atoms, arylene having from 6 to 12 carbon atoms, a saturated divalent cycloaliphatic group having from 6 to 10 carbon atoms, arylene alkylene or alkylenearylene having from 7 to 14 atoms of carbon, or arylene-alkylenearylene having from 13 to 16 carbon atoms. R as lower alkylene preferably has up to 8 carbon atoms, and can be straight or branched chain. Suitable examples include octylene, hexylene, pentylene, butylene, propylene, ethylene, methylene, 2-propylene, 2-butylene, and 3 -pentylene. R as lower alkylene preferably has up to 6, and especially preferably up to 4 carbon atoms. The meanings of methylene and butylene are especially preferred. R1 is preferably hydrogen or lower alkyl having up to 7, especially up to 4 carbon atoms, especially hydrogen. R4 or R5 as lower alkylene, preferably has from 2 to 6 carbon atoms, and is especially straight chain. Suitable examples include propylene, butylene, hexylene, dimethylethylene, and especially preferably ethylene. R 4 or R 5 as arylene is preferably phenylene which is unsubstituted or substituted by lower alkyl or lower alkoxy, especially 1,3-phenylene or 1,4-phenylene or methyl-1,4-phenylene. R 4 or R 5 as a saturated divalent cycloaliphatic group is preferably cyclohexylene or cyclohexylene-lower alkylene, for example cyclohexylenemethylene, which is unsubstituted or is substituted by one or more methyl groups, such as, for example, trimethylcyclohexylenemethylene, for example the radical of divalent isophorone. The alkylenearylene or arylenealkylene arylene unit such as R4 or R5, is preferably phenylene, unsubstituted or substituted by lower alkyl or lower alkoxy, and the alkylene unit thereof is preferably lower alkylene, such as methylene or ethylene, especially methylene . These radicals R4 or R5, therefore, are preferably phenylenemethylene or methylenephenylene. R 4 or R 5 as arylene-alkylene-arylene is preferably phenylene-lower alkylene-phenylene having up to 4 carbon atoms in the alkylene unit, for example phenylene-ethylene-phenylene.

The radicals R4 and R5 are each independently, preferably, lower alkylene having from 2 to 6 carbon atoms, phenylene, unsubstituted or substituted by lower alkyl, cyclohexylene or cyclohexylene-lower alkylene, unsubstituted or substituted by lower alkyl, lower phenylene alkylene, lower alkylene phenylene, or lower phenylene alkylene phenylene. Within the scope of this invention, the term "lower" used in relation to radicals and compounds, denotes radicals or compounds having up to 7 carbon atoms, preferably up to 4 carbon atoms, unless otherwise defined. Lower alkyl has especially up to 7 carbon atoms, preferably up to 4 carbon atoms, and is, for example, methyl, ethyl, propyl, butyl, or tertiary butyl. Lower alkoxy has especially up to 7 carbon atoms, preferably up to 4 carbon atoms, and is, for example, methoxy, ethoxy, propoxy, butoxy, or tertiary butoxy. The olefinically unsaturated copolymerizable radical R3 having from 2 to 24 carbon atoms is preferably alkenyl having from 2 to 24 carbon atoms, especially alkenyl having from 2 to 8 carbon atoms, and especially preferably alkenyl which it has from 2 to 4 carbon atoms, for example ethenyl, 2-propenyl, 3-propenyl, 2-butenyl, hexenyl, octenyl, or dodecenyl. The meanings of ethenyl and 2-propenyl are preferred, such that the group -CO-R 3 is the acyl radical of acrylic or methacrylic acid. The divalent group -R4-NH-CO-0- is present when q is 1, and is absent when q is zero. Prepolymers are preferred where q is zero. The divalent group -CO-NH- (R4-NH-CO-0) q-R5-0- is present when p is one, and is absent when p is zero. Prepolymers are preferred where p is zero. In the prepolymers where p is one, the index q is preferably zero. Especially preferred are the prepolymers wherein p is one, the index q is zero, and R5 is lower alkylene. A preferred prepolymer is a derivative of a polyvinyl alcohol having a molecular weight of at least about 2,000 which, based on the number of hydroxyl groups - of the polyvinyl alcohol, comprises from about 0.5 to about 80 percent units of the formula III, wherein R is lower alkylene having up to 6 carbon atoms, p is zero, and R3 is alkenyl having from 2 to 8 carbon atoms. A further preferred prepolymer is a derivative of a polyvinyl alcohol having a molecular weight of at least about 2,000, which, based on the number of hydroxyl groups of the polyvinyl alcohol, comprises from about 0.5 to about 80 percent of units of formula III wherein R is lower alkylene having up to 6 carbon atoms, p is one, q is zero, R5 is lower alkylene having 2 to 6 carbon atoms, and R3 is alkenyl having from 2 to 8 carbon atoms. Yet a further preferred prepolymer is a derivative of a polyvinyl alcohol having a molecular weight of at least about 2,000 which, based on the number of hydroxyl groups of the polyvinyl alcohol, comprises from about 0.5 to about 80 percent units of the polyvinyl alcohol. Formula III, wherein R is lower alkylene having up to 6 carbon atoms, p is one, q is one, R 4 is lower alkylene having from 2 to 6 carbon atoms, phenylene, unsubstituted or substituted by lower alkyl, cyclohexyl- no, or lower cyclohexylenealkylene, unsubstituted or substituted by lower alkyl, lower phenylenenalkylene, lower alkylene-phenylene, or lower phenylene-alkylene-phenylene, R5 is lower alkylene having from 2 to 6 carbon atoms, and R3 is alkenyl having from 2 to 6 carbon atoms; 8 carbon atoms. Preferred prepolymers are preferably polyvinyl alcohol derivatives having a molecular weight of at least about 2,000, which, based on the number of hydroxyl groups of the polyvinyl alcohol, comprises from about 0.5 to about 80 percent, especially from about 1 to 50 percent, preferably from about 1 to 25 percent, preferably about 2 to 15 percent, and especially preferably about 3 to 10 percent of units of formula III. The preferred prepolymers that are used for the manufacture of contact lenses comprise, based on the number of hydroxyl groups of the polyvinyl alcohol, especially from about 0.5 to about 25 percent, especially from about 1 to 15 percent, and from an especially preferable manner of about 2 to 12 percent of units of formula III. The polyvinyl alcohols that can be derivatized to obtain a preferred prepolymer, preferably have a molecular weight of at least 10,000. As an upper limit, polyvinyl alcohols can have a molecular weight of up to 1,000,000. Preferably, the polyvinyl alcohols have a molecular weight of up to 300,000, especially up to about 100,000, and especially preferably up to about 50,000. Suitable polyvinyl alcohols according to the invention typically have a structure of poly (2-hydroxy) e-tylene. However, the polyvinyl alcohols can also comprise hydroxyl groups in the form of 1,2-glycols, such as 1,2-dihydroxyethylene copolymer units, as can be obtained, for example, by alkaline hydrolysis of acetate copolymers. vinyl / vinylene carbonate.

In addition, the polyvinyl alcohols to obtain a preferred prepolymer may also comprise small proportions, for example up to 20 percent, preferably up to 5 percent copolymer units of ethylene, propylene, acrylamide, methacrylamide, dimethacrylamide, hydroxyethyl methacrylate , methyl methacrylate, methyl acrylate, ethyl acrylate, vinyl pyrrolidone, hydroxyethyl acrylate, allyl alcohol, styrene, or similar comonomers used by custom. Commercially available polyvinyl alcohols can be used, such as, for example, Vinol® 107 produced by Air Products (Molecular weight = 22,000 to 31,000, 98 to 98.8 percent hydrolysed), Polysciences 4397 (Molecular weight = 25,000, 98.5 percent hydrolyzed) , BF 14 produced by Chan Chun, Elvanol® 90-50 produced by DuPont, UF-120 produced by Unitika, MoviolR 4-88, 10-98, and 20-98 produced by Hoechst.

Other manufacturers are, for example, Nippon Gohsei (Gohsei (GohsenolR), Monsanto (GelvatolR), Wacker (PolyviolR) and the Japanese manufacturers Kuraray, Denki, and Shin-Etsu. The molecular weights referenced herein are weight average weights, Mw, determined by gel permeation chromatography, unless otherwise specified. As already mentioned, it is also possible to use hydrolyzed vinyl acetate copolymers, which can be obtained, for example, in the form of ethylene / vinyl acetate (EVA), or vinyl chloride / vinyl acetate, N-vinyl pyrrolidone / vinyl acetate, and maleic acid anhydride / vinyl acetate, hydrolysates. The polyvinyl alcohol is usually prepared by hydrolysis of the corresponding homopolymer polyvinyl acetate. In a preferred embodiment, the polyvinyl alcohol to obtain a preferred prepolymer comprises less than 50 percent polyvinyl acetate units, especially less than 20 percent polyvinyl acetate units. The preferred amounts of residual acetate units in the polyvinyl alcohol to obtain a preferred prepolymer, based on the sum of vinyl alcohol units and acetate units, are from about 3 to 20 percent, preferably from about 5 to 16 percent. percent, and especially from about 10 to 14 percent. The compounds comprising units of the formula III can be prepared in a manner known per se. The prepolymers of formulas I and III are extremely stable. The prepolymers of formulas I and III can be further purified in a manner known per se, for example, by acetone precipitation, dialysis or ultrafiltration, ultrafiltration being especially preferred. By means of this purification process, the prepolymers of formulas I and III can be obtained in an extremely pure form, for example in the form of aqueous solutions concentrates that are exempt, or at least substantially free, from reaction products. The prepolymers of formulas I and III can be crosslinked in an extremely effective and controlled manner, especially by photocrosslinking. Molded articles can be obtained by photocrosslinking a prepolymer comprising units of formula I or III, in the absence or in the presence of an additional vinyl comonomer. These polymers are insoluble in water. In the case of photocrosslinking, it is appropriate to add a photoinitiator, which can initiate radical crosslinking. The photopolymerization can occur in the presence of a solvent, which is preferably water. The photocrosslinking is preferably carried out directly from an aqueous solution of the preferred prepolymers, which can be obtained by the preferred purification step, ultrafiltration, where appropriate after the addition of an additional vinyl comonomer. For example, an aqueous solution of about 15 to 40 percent can be photoreticulated. The vinyl comonomer which, according to the invention, can be used in addition in the photocrosslinking, can be hydrophilic or hydrophobic, or a mixture of a hydrophobic and a hydrophilic vinyl monomer. Suitable vinyl monomers include especially those that are used by custom in the manufacture of contact lenses, and are known to people who have ordinary experience in this field. In general, about 0.01 to 80 units of a typical vinyl comonomer react per unit of formula I or III. If a vinyl comonomer is used, the crosslinked polymers preferably comprise from about 1 to 15 percent, especially preferably from about 3 to 8 percent, of units of formula I or III, based on the number of hydroxyl groups of the polyvinyl alcohol, which are reacted with from about 0.1 to 80 units of the vinyl monomer. The proportion of vinyl comonomers, if used, is preferably from 0.5 to 80 units per unit of formula I, especially from 1 to 30 units per unit of formula I, and especially preferably from 5 to 20 units. per unit of formula I. Preparing a substantially aqueous solution of a soluble prepolymer in water comprising crosslinkable groups may be performed in a manner known per se, for example by synthesis of the prepolymer in a substantially aqueous solution or by isolating the prepolymer, for example in pure form (ie, free from undesired constituents), and their dissolution in a substantially aqueous medium.

Substantially aqueous solutions of the prepolymer include in particular solutions of the prepolymer in water, in aqueous salt solutions, especially in aqueous solutions having an osmolarity of about 200 to 450 miliosmo-les per 1,000 milliliters (unit: mOsm / 1), preferably a osmolarity of about 250 to 350 mOsm / 1, especially about 300 mOsm / 1, or in mixtures of water or aqueous salt solutions with physiologically tolerable polar organic solvents, such as, for example, glycerol. Prepolymer solutions in water or aqueous salt solutions are preferred. The substantially aqueous solution of the prepolymer defined hereinbefore, is preferably a pure solution, which means a solution that is free or essentially free of undesired constituents. Especially preferred examples of these solutions are a solution of the prepolymer in pure water or in an artificial tear fluid. The viscosity of the prepolymer solution in the substantially aqueous solution, within wide limits, is not critical, but the solution should preferably be a flowable solution that can be deformed without stresses. The molecular weight of the prepolymer, too, within wide limits, is not critical. Preferably, however, the prepolymer has a molecular weight of from about 10,000 to about 200,000. In a preferred embodiment, the prepolymer contains crosslinkable groups. "Crosslinkable groups" denotes customary crosslinkable groups well known to the person skilled in the art, such as, for example, photocrosslinkable or thermally crosslinkable groups. Crosslinkable groups, such as those already proposed for the preparation of materials for contact lenses, are especially suitable. These include especially, but not exclusively, groups that comprise carbon-carbon double bonds. To demonstrate the large variety of suitable crosslinkable groups, there are mentioned here, merely by way of example, the following crosslinking mechanisms: radical polymerization, 2 + 2 cycloaddition, Diels-Alder reaction, ROMP (metathesis polymerization ring-opening ), vulcanization, cationic crosslinking, and epoxy hardening. Soluble prepolymers suitable water comprising crosslinkable groups are, for example, compounds comprising units of formula I. However, it is also possible to use in the process other water-soluble prepolymers that comprise a polymeric base structure, and also crosslinkable groups . Suitable polymeric base structures include, in addition to polyvinyl alcohol, materials such as those already proposed in some cases as contact lens materials, for example polymeric diols other than polyvinyl alcohol, polymers comprising saccharides, polymers which comprise vinyl pyrrolidone, polymers comprising alkyl (meth) acrylates, polymers comprising alkyl (meth) acrylates that have been replaced by hydrophilic groups, such as by hydroxyl, carboxyl, or by amino, polyalkylene glycols, or copolymers or mixtures thereof. The prepolymer used according to the invention preferably comprises crosslinkable groups in an amount of about 0.5 to about 80 percent equivalents, based on the equivalents of the monomers forming the polymeric base structure, especially about 1 to 50 percent, preferably from about 1 to 25 percent, preferably from about 2 to 15 percent, and especially preferably from about 3 to 10 percent. Also especially preferred are amounts of crosslinkable groups of from about 0.5 to about 25 percent equivalents, especially from about 1 to 15 percent, and especially preferably from about 2 to 12 percent, based on the equivalents of monomers that form the polymeric base structure. As already mentioned, a criterion for the property of a preferred prepolymer is that it is a crosslinkable prepolymer, but the prepolymer is not crosslinked, or at least is not substantially crosslinked, such that it is soluble in water. In addition, the prepolymer is conveniently stable in the non-crosslinked state, such that it can be subjected to purification as described hereinabove in relation to the compounds comprising units of the formula I. The prepolymers are preferably used in the form of a pure solution in the process according to the invention. The prepolymers can be converted to the form of a pure solution, for example, in the manner disclosed hereinafter. Preferably, the prepolymers used in the process according to the invention, can be purified in a manner known per se, for example, by precipitation with organic solvents, such as acetone, filtration, and washing, extraction in a suitable solvent, dialysis or ultrafiltration, ultrafiltration being especially preferred. By means of this purification process, the prepolymers can be obtained in an extremely pure form, for example, in the form of concentrated aqueous solutions which are exempt, or at least substantially free, from reaction products, such as salts, and from starting materials, such as, for example, non-polymeric constituents. The preferred purification process for the prepolymers used in the process according to the invention, ultrafiltration, can be carried out in a manner known per se. It is possible that ultrafiltration is carried out repeatedly, for example, two to ten times. In an alternative way, The ultrafiltration can be carried out continuously, until the selected degree of purity is obtained. The degree of purity selected, in principle, can be as high as desired. An appropriate measure for the degree of purity is, for example, the sodium chloride content of the solution, which can be determined simply in a known manner. In a preferred embodiment of the process according to the invention, a substantially aqueous solution of the prepolymer is prepared, which is substantially free of undesired constituents, such as, for example, free of monomeric, oligomeric, or polymeric starting materials used for the preparation of the prepolymer, and / or free of by-products formed during the preparation of the prepolymer. The substantially aqueous solution is more preferably a pure aqueous solution, or a solution in an artificial tear fluid, as defined hereinabove. It is also preferable to carry out the process according to the invention, without the addition of a comonomer, for example a vinyl comonomer. Based on one of the measures mentioned in the previous paragraph, and especially based on a combination of the measures mentioned in the previous paragraph, the solution of the prepolymer used in the process according to the invention, is one that does not comprise, or which substantially does not comprise undesired constituents that have to be extracted after a crosslinking operation. A particular feature of this preferred embodiment of the process according to the invention, therefore, is that the removal of unwanted constituents can be eliminated following cross-linking. Accordingly, the process according to the invention is preferably carried out in such a way that the substantially aqueous solution of the water-soluble prepolymer comprising crosslinkable groups is free or substantially free of undesired constituents, such as especially monomeric starting materials, oligomeric, or polymeric used for the preparation of the prepolymer, or by-products that have been formed during the preparation of the prepolymer, and / or that the solution is used without the addition of a comonomer, in such a way that the extraction of the any undesired constituents in the additional course of the process. An additive that is added, where appropriate, to the prepolymer solution, is an initiator for crosslinking, if an initiator is required to crosslink the crosslinkable groups. This may be the case especially if the crosslinking is carried out by photocrosslinking, which is preferred in the process according to the invention. In the case of photocrosslinking, it is appropriate to add a photoinitiator that can initiate radical crosslinking. The examples thereof are familiar to the person skilled in the art, and the photoin- Suitable excipients which may be specifically mentioned are benzoin methyl ether, 1-hydroxycyclohexylphenyl ketone, or a commercial product such as the DAROCURR or IRGACURR types, for example DAROCURR 1173 or IRGACURR 2959. The crosslinking is triggered in the mold, for example, by actinic radiation, such as, for example, ultraviolet light, or by ionizing radiation, such as, for example, gamma radiation, electron radiation, or X radiation. Ultraviolet (UV) radiation is preferred. Crosslinking, where appropriate, can also be thermally triggered. Attention is drawn to the fact that the crosslinking can be carried out according to the invention in a very short time, for example in less than 5 minutes, preferably in less than 1 minute, more preferably in up to 30 seconds, and especially in less than 10 seconds Because the prepolymer solution preferably does not comprise undesirable low molecular weight constituents, the crosslinked product also does not comprise any of these constituents. Therefore, a subsequent extraction is not necessary. Because the crosslinking is carried out in a substantially aqueous solution, subsequent hydration is not necessary. These two advantages mean, among other things, that a complicated subsequent treatment of the resulting molded articles, especially contact lenses, is eliminated. Contact lenses that can be obtained in accordance with The process of the invention, therefore, are distinguished by the fact that they are suitable for their intended use without extraction. "Intended use" in this context, means especially that contact lenses can be used in the human eye. The contact lenses that can be obtained according to the process of the invention are also distinguished by the fact that they are suitable for their intended use without hydration. The invention has been described in detail, with reference to certain preferred embodiments, in order to enable the reader to practice the invention without undue experimentation. However, a person having ordinary experience in this field will readily recognize that many of the components and parameters may be varied or modified to some degree, without departing from the scope and spirit of the invention. In addition, titles, headings, definitions, or the like, are provided to improve reader understanding of this document, and should not be read to limit the scope of the present invention. In accordance with the foregoing, the intellectual property rights to this invention are defined only by the following claims and their extensions and reasonable equivalents.

Claims (79)

1. A cyclic process for the production of a plurality of molded articles, which comprises: (a) dosing a prepolymer material in a female mold half; (b) coupling a male mold half to the female mold half; (c) applying radiation to crosslink and / or polymerize the prepolymer material, in order to form a molded article; (d) separating the male mold half from the female mold half; (e) washing the molded article to remove the unreacted prepolymer; (f) ensuring that the molded article is adjacent to a selected mold half; (g) holding the molded article in a central area to remove the molded article from the selected mold half; (h) deposit an acceptable molded article in the package; (i) cleaning the male and female mold halves; and (j) advancing the male and female mold halves up a position to dose the prepolymer.

2. A process of claim 1, wherein this process includes at least one step of inspecting the molded articles.

A process of claim 2, wherein this inspection comprises: (1) inspecting the central portions of the molded article to determine defects; and (2) inspect the peripheral regions of the molded article to determine defects.

A process of claim 1, wherein this process further comprises the step of centering the molded article inside the female mold half before the step of holding the molded article in a central area to remove the molded articles from the middle of the mold. mold.

A process of claim 3, which further comprises at least partially drying the molded article to remove the surface water, which may impair the inspection of the molded articles, before the step of inspecting the edges of the molded articles to determine defects .

6. A process of claim 3, wherein the inspection of the central portions of the molded articles to determine defects, occurs immediately after the step of applying radiation to crosslink and / or polymerize the prepolymer material

7. A process of claim 1, wherein the cycle time for each step is less than about 1 minute.

8. A process of claim 7, wherein the cycle time for each step is less than about 10 seconds.

9. A process of claim 1, wherein the step of ensuring that the molded article is adjacent to the selected mold half, comprises a step of transferring any molded articles resting on the non-selected mold half towards the middle of the mold. corresponding selected mold.

10. A process of claim 9, wherein the mold half selected is the female mold half, and the unselected mold half is the male mold half.

11. A process for the production of a plurality of molded articles using a plurality of molds, which comprises: (a) dosing a prepolymer in the female mold halves; (b) coupling the male mold halves to the female mold halves; (c) applying radiation to crosslink the crosslinkable material in order to form molded articles; (d) inspecting the central portions of the molded articles to determine defects; (e) separating the male mold halves from the female mold halves; (f) washing the mold halves to remove the unreactable crosslinking material; (g) transferring any molded articles that are on the male mold halves, to the female mold halves; (h) centering the molded articles inside the female mold halves; (i) fastening the molded articles in a central area to remove the molded articles from the mold halves; (j) at least partially drying molded articles to remove surface water, which may impair the inspection of molded articles; (k) inspect the edges of the molded articles to determine defects; (1) deposit acceptable molded articles in packages; (m) clean male and female mold halves; and (n) advancing the male and female mold halves to a position for dosing the crosslinkable material.

12. A process of claim 1, wherein the prepolymer is a derivative of a polyvinyl alcohol having a weight average molecular weight, M ^, of at least about 2,000, which, based on the number of hydroxyl groups of the polyvinyl alcohol, comprises from about 0.5 to about 80 percent of units of the formula I: wherein: R is lower alkylene having up to 8 carbon atoms, R1 is hydrogen or lower alkyl, and R2 is an olefinically unsaturated copolymerizable electron attracting radical.

13. A process of claim 1, wherein the molded articles are ophthalmic lenses.

14. A molding process of claim 13, wherein the ophthalmic lenses are contact lenses.

15. A process of claim 11, wherein the molded articles are ophthalmic lenses.

16. A process of claim 1, wherein the Dosage is conducted in an atmosphere having a relative humidity of at least 55 percent.

17. A process of claim 1, wherein the dosage is conducted through a dosing tip which remains in contact with the polymerizable and / or crosslinkable material upon completion of the dosage.

18. A process of claim 1, wherein the mold halves are reused to produce at least 10,000 molded articles.

A process of claim 1, which utilizes a molding assembly that houses a plurality of removable male and female mold halves, comprising a male molding assembly housing a plurality of male mold halves removably attached to the mold. same; and a female molding assembly accommodating a plurality of female mold halves removably affixed thereto, wherein the coupling of the male and female mold halves is accomplished by: (a) articulating the male assembly in an arcuate movement; and (b) subsequently moving the male assembly in a substantially linear manner to a position where the male and female mold halves are coupled.

20. A process of claim 1, wherein a plurality of male mold halves are coupled with a plurality of corresponding female mold halves, and all this coupling occurs in a substantially simultaneous manner.

21. A process for the manufacture of ophthalmic lenses, which comprises a step of coupling a male mold half, which is releasably fixed to a male mold housing, with a female mold half, which is fixed from a releasably way to a female mold housing, wherein the male mold housing and the female mold housing are fixed on one another by an articulation element, this step comprising coupling the male and female mold halves: (a) articulating the male mold housing around the articulation element, at a relatively fast angular articulation speed, to a position where the corresponding male and female mold halves are substantially aligned; and (b) moving the male mold housing in a substantially linear manner, at a relatively slow speed to a position where the corresponding male and female mold halves are engaged to form molding cavities.

22. A process of claim 21, wherein the articulation of the male die housing occurs over an angle of about 90 ° to about 270 ° relative to the female mold housing.

23. A process of claim 22, wherein the The articulation of the male mold housing occurs at an angle of about 150 ° to about 210 ° relative to the female mold housing.

24. A process of claim 21, wherein the angular joint occurs at a speed of approximately 100 ° to approximately 500 ° per second.

25. A process of claim 21, wherein the linear movement occurs at a rate of from about 0.1 to about 2.0 millimeters per second.

26. A process of claim 21, wherein each of the housings includes a plurality of mold halves that are fixed in a removable manner to the housings.

27. A process of claim 26, wherein each of the housings includes from about 5 to about 20 mold halves.

A process of claim 21, wherein from about 5 to about 20 male mold halves are removably attached to the male mold housing, and a corresponding number of female mold halves are removably attached to the housing of female mold, wherein the housings are joined in an articulated manner to one another, and wherein the mold halves are engaged by: (a) articulating the male mold housing around the articulated joint, at a speed of approximately 100 ° to approximately 500 ° per second, to a position where the corresponding male and female mold halves are substantially aligned; and (b) moving the male mold housing in a substantially linear manner, at a rate of from about 0.1 to about 2.0 millimeters per second, to a position where the corresponding male and female mold halves are engaged to form molding cavities.

29. A molding assembly including a plurality of removable male and female mold halves, which comprises: (a) a male housing having a plurality of male mold halves that are removably attached to the male housing; and (b) a female housing having a plurality of female mold halves removably affixed to the female housing, wherein these housings are fixed to each other, such that at least one of the housings can be angularly articulated to a wherein the male and female mold halves are substantially aligned, such that a substantially linear movement of at least one of the housings can be made to a position where the male and female mold halves are coupled.

30. A molding assembly of claim 29, wherein each of the male and female molding assemblies includes from about 5 to about 20 mold halves.

31. A molding assembly of claim 30, wherein the mold halves of each of the male and female molding assemblies are configured in an array of two or more rows, each row having an equal number of mold halves. , this number being from 3 to 10.

32. A molding assembly of claim 29, wherein at least one of the set of male mold halves or the set of female mold halves is formed of quartz.

A molding assembly of claim 29, wherein the mold halves of at least one of the set of male mold halves or the set of female mold halves includes a peripheral region that blocks ultraviolet light during polymerization and / or cross-linking, thus defining precisely the edge of the lenses that are formed.

34. A molding assembly of claim 29, wherein the male and female mold halves are reused to produce at least 10,000 lenses.

35. A process for the manufacture of ophthalmic lenses, which includes a cyclic configuration of steps, wherein the mold halves are cleaned and reused.

36. A process of claim 35, wherein the mold halves are used to produce at least 1,000 glasses .

37. A process of claim 36, wherein the mold halves are used to produce at least 10,000 lenses.

38. A process of claim 43, wherein the mold halves are used to produce at least 1,000,000 lenses.

39. A process of claim 37, wherein the ophthalmic lenses are contact lenses.

40. A process for the production of ophthalmic lenses, which includes a step of dosing a liquid prepolymer in a female mold half, in an atmosphere having a relative humidity of at least 55 percent.

41. A process of claim 40, wherein the relative humidity is from about 60 percent to about 80 percent.

42. A process of claim 40, wherein the dosage is conducted at a height of about 0.1 millimeters to about 5 millimeters from a surface of the female mold half.

43. A process of claim 42, wherein the dosage is conducted at a height of about 1 millimeter to about 3 millimeters from a surface of the female mold half.

44. A process of claim 43, wherein the dosage is conducted at a height of approximately 1.5 millimeters to approximately 2.5 millimeters from a surface of the female mold half.

45. A process of claim 40, wherein the dosage is conducted at a horizontal distance of about 1 to about 6 millimeters from the central axis of symmetry of the mold half.

46. A process of claim 45, wherein the dosage is conducted at a horizontal distance of about 4 to about 6 millimeters from the central axis of symmetry of the mold half.

47. A process of claim 40, wherein the dosage is conducted: (a) in an atmosphere having a relative humidity of at least 55 percent; (b) at a height of about 0.1 millimeters to about 5 millimeters from a surface of the female mold half; and (c) at a horizontal distance of about 1 to about 6 millimeters from the central axis of symmetry of the mold half.

48. A process of claim 47, wherein the dosage is conducted: (a) in an atmosphere having a relative humidity of about 60 percent to about 80 percent hundred; (b) at a height of about 1 millimeter to about 3 millimeters from a surface of the female mold half; and (c) at a horizontal distance of about 4 to about 6 millimeters from the central axis of symmetry of the mold half. .

49. A process of claim 40, wherein the dosage is conducted through a dosing tip that remains in contact with the polymerizable and / or crosslinkable material, upon completion of the dosage.

50. A process for cleaning an ophthalmic molded article that is disposed on a mold half to remove the unreacted prepolymer material from which the lens was formed, which comprises: (a) applying a stream of liquid to the lens; and (b) simultaneously apply a vacuum to remove the effluent; where this process does not dislodge the molded article from the middle of the mold.

51. A cleaning process of claim 50, which further comprises applying one or more air streams to the lens.

52. A cleaning process of claim 50, wherein the vacuum is applied vertically on top of the lens, while peripherally applying water to the lens.

53. A cleaning process of claim 50, which comprises: (a) applying a plurality of liquid streams peripherally aqueous to the lens; (b) applying a plurality of air streams peripherally to the lens; and (c) apply a vacuum vertically on the lens to remove the effluent.

54. A process of claim 50, wherein the liquid has a conductivity greater than about 1,000 micro-Siemens.

55. A process for centering an ophthalmic molded article on a female mold half, which comprises: (a) dosing an aqueous solution on the female mold half in a first stage; (b) dosing a lens, with the concave side facing up, into a female mold half in a second step; and (b) advancing the lens to a third stage, thereby providing the lens with sufficient lubrication and time to center the lens inside the female mold half.

56. A process of claim 55, wherein the liquid is an aqueous solution.

57. A process of claim 55, wherein the liquid is applied along the periphery of the lens.

58. A process of claim 55, wherein from about 0.05 to about 0.20 milliliters of an aqueous solution is dosed onto the lens.

59. A process of claim 55, wherein the liquid has a conductivity greater than about 1,000 micro-Siemens.

60. A method for ensuring that an ophthalmic lens is located on a selected mold half in a two-sided ophthalmic lens molding process, which comprises: (a) moving a first fastener to a position adjacent to a location of resting the lens on a first half of the mold; (b) activating the first clamping element, thereby removing any lens that rests on the first half of the mold; (c) moving the first fastening element to a position adjacent to a second fastening element; (d) activating the second clamping element, and deactivating the first clamping element, thereby transferring any lens stopped by the first clamping element, to the second clamping element; (e) moving the second securing element to a position adjacent to the second half of the mold; Y (f) deactivating the second clamping element, thereby releasing any lens retained by it, on the second mold half.

61. A method of claim 60, wherein the selected mold half is a female mold half.

62. A method of claim 60, wherein each of the first and second fastening elements comprises a robotic arm having vacuum tubing connected thereto, this tubing providing a conduit for a holding end of the robotic arm., wherein the activation of the clamping element occurs when a valve is opened to allow a vacuum to be exerted on that clamping end, and deactivation occurs when a valve is closed, thereby discontinuing the vacuum.

63. A method of claim 62, wherein the deactivation further comprises applying a positive air pressure through the holding end of the robotic arm.

64. A method of claim 60, wherein this method is a step in a cyclic lens production process, and wherein activation and deactivation are signaled by an electronic control element, which controls the cyclic production process Of lenses.

65. A process for inspecting the peripheral areas of an ophthalmic lens that is held and stabilized in a central area of the lens, which comprises: (a) fastening and stabilizing an ophthalmic lens in a central region; (b) illuminating a peripheral region of the ophthalmic lens; (c) forming an image of the peripheral region of the ophthalmic lens with a camera element; and (d) evaluating the image in order to determine if a lens is rejected or the process parameters are adjusted.

66. A process of claim 65, wherein the water is removed from the lens prior to inspection, without substantially dehydrating the lens.

67. A process for producing an ophthalmic molded article product finished from a liquid prepolymer material, wherein the lens product is packaged in a suitable container for distribution to consumers, and where this process is completed in less than approximately 20 minutes.

68. A process of claim 67, wherein this process is completed in less than about 10 minutes.

69. A process of claim 68, wherein this process is completed in less than about 2 minutes.

70. A process of claim 69, wherein this process is completed in less than about 1 minute.

71. A process of claim 67, wherein at least a portion of the process is cyclic, and the molds used in the process are repeatedly used again.

72. A process of claim 71, wherein the molds are used at least 10,000 times.

73. A process of claim 72, wherein the molds are reused at least 1,000,000 times.

74. A process for the manufacture of ophthalmic lenses, wherein this process includes more than one series of steps that are of a cyclic nature, which comprises: (a) a first cycle of repetition that includes the steps of: (1) dosing a liquid prepolymer in a reusable mold including male and female mold halves; (2) forming the lens; and (3) separating the mold halves; and (b) a second cycle of repetition that includes: (1) removing the lens from one half of the mold; and (2) transfer the lens to a packaging process.

75. A process of claim 74, wherein: (a) the first repeat cycle includes the steps of: (1) dosing a prepolymer material in a female mold half; (2) coupling a male mold half with the female mold half; (3) apply radiation for reticular and / or polyme- crimping the prepolymer material, in order to form an ophthalmic lens; (4) separating the male mold half from the female mold half; and (b) the second repeat cycle includes the step of: (1) depositing the acceptable molded articles in packages.

76. A process of claim 75, wherein: (a) the first repeat cycle includes the steps of: (1) dosing a prepolymer material in a female mold half; (2) coupling a male mold half with the female mold half; (3) applying radiation to crosslink and / or polymerize the prepolymer material, in order to form an ophthalmic lens; (4) separating the male mold half from the female mold half; (5) washing the lens to remove the unreacted prepolymer, - (6) ensuring that the lens is adjacent to a selected mold half; (7) clean the male and female mold halves; Y (8) advancing the male and female mold halves to a position for dosing the prepolymer; and (b) the second repeat cycle includes the steps of: (1) securing the lenses in a central area to remove the molded article from the selected mold half, - (2) depositing the molded articles acceptable in packages; and (3) dispose of unacceptable lenses in a waste container.

77. A process of claim 76, wherein: (a) the first repeat cycle includes the steps of: (1) dosing a prepolymer material in a female mold half; (2) coupling a male mold half with the female mold half; (3) applying radiation to crosslink and / or polymerize the prepolymer material, in order to form an ophthalmic lens; (4) separating the male mold half from the female mold half; (5) wash the lens to remove the unreacted prepolymer; (6) ensure that the lens is adjacent to a half of mold selected; (7) inspecting a central region of the ophthalmic lens; (8) clean the male and female mold halves; and (9) advancing the male and female mold halves to a position for dosing the prepolymer; and (b) the second repeat cycle includes the steps of: (1) securing the lenses in a central area to remove the molded article from the selected mold half; (2) inspecting a peripheral region of the ophthalmic lens; (3) deposit acceptable molded articles in packaging; and (4) dispose of unacceptable lenses in a waste container.

78. A process of claim 74, wherein the molds are reused at least 10,000 times.

79. A process of claim 74, wherein the process is completed in less than about 20 minutes.