Abstract:
There is described a method of separating excess lens forming material from a molded ophthalmic lens, in particular a contact lens. After polymerization and/or cross-linking of a lens forming material (P) within a mold cavity (4) of a mold (1) comprising female and male mold halves (2, 3) to form an ophthalmic lens non-polymerized and/or non-cross-linked lens forming material is flushed away from the mold halves (2, 3) with a jet of a fluid flushing medium, such as, e.g., water or a solvent or an inert gas. Subsequently the molded lens is dried. In accordance with the invention the flushing is accomplished with the mold halves (2, 3) still in the closed position. There is also described an apparatus for carrying out the method.
Abstract:
A method for avoiding the entrapment of air bubbles (5) in a lens forming material, in particular in a low viscosity lens forming material, in an ophthalmic lens manufacturing process using mold halves (2; 3) each having a lens forming surface (21; 31) comprises electrostatically charging a predetermined portion of the lens forming surface (21; 31) of the mold half (2; 3) prior to the predetermined portion of the lens forming surface (21; 31) coming into contact with the lens forming material (4).
Abstract:
Described herein is a cost-effective and time-efficient method for making UV-absorbing contact lenses. In contrast to the conventional method for making UV-absorbing contact lenses which involves copolymerizing a lens forming composition including a UV-absorbing vinylic monomer, a method of the invention involves dipping a contact lens in a solution of UV-absorbing polymer comprising carboxyl-containing monomeric units, UV-absorbing monomeric units and covalently bound radical-initiating moieties to form a UV-absorbing coating on the contact lens.
Abstract:
The invention provides a method for washing, with a water-based system, reusable molds for making silicone hydrogel contact lenses. The water-based washing system comprises a solvo-surfactant which is an alkyl (propylene glycol)n ether wherein alkyl is a linear alkyl group having 2 to 5 carbon atoms and n is the integer 1, 2 or 3. The water-based system of the invention can effectively wash away silicone-containing components and other components of a lens formulation left behind on the molding surfaces of a reusable mold, after removing a silicone hydrogel contact lens cast molded in the reusable mold.
Abstract:
There is described a method of separating excess lens forming material from a molded ophthalmic lens, in particular a contact lens. After polymerization and/or cross-linking of a lens forming material (P) within a mold cavity (4) of a mold (1) comprising female and male mold halves (2, 3) to form an ophthalmic lens non-polymerized and/or non-cross-linked lens forming material is flushed away from the mold halves (2, 3) with a jet of a fluid flushing medium, such as, e.g., water or a solvent or an inert gas. Subsequently the molded lens is dried. In accordance with the invention the flushing is accomplished with the mold halves (2, 3) still in the closed position. There is also described an apparatus for carrying out the method.
Abstract:
There is described a process for manufacturing an ophthalmic lens and an apparatus for forming an ophthalmic lens, in particular a silicone hydrogel contact lens, wherein in a mold assembly a first and a second mold half (101, 102) are first arranged in an intermediate closed position in which the mold surfaces of the two mold halves are spaced apart from each other at a distance increase (d1) of preferably 1 to 100 μm relative to a final distance (d0) in a final closed position, and wherein, during curing of the lens forming material (202), the mold surfaces (105, 106) of the mold halves (101, 102) are actively or passively moved or moving from the intermediate closed position to the final closed position, where the distance increase (d1) is 0.
Abstract:
A modular production line for the production of contact lenses comprises at least three separate modules: a manufacturing module (MM), an inspection module (IM), and a packaging module (PP). The modular production line further comprises fixedly arranged transfer interfaces between the individual modules (MM, IM, PP) for transferring the lenses from a preceding module to a subsequent module. The manufacturing module (MM) comprises a plurality of manufacturing stations (300, 301, 302, 310, 320, 321, 322, 330, 331, 340, 341, 342, 350, 351, 352) which are grouped to form a plurality of individual manufacturing units (30; 31; 32; 33; 34; 35) arranged in a closed loop. Reusable male and female molds (212, 112) are transported through the manufacturing stations of the manufacturing units, and each manufacturing unit (30; 31; 32; 33; 34; 35) comprises a plurality of the manufacturing stations (300, 301, 302, 310, 320, 321, 322, 330, 331, 340, 341, 342, 350, 351, 352). A plurality of transfer robots (36) is provided, each transfer robot (36) of the plurality of transfer robots (36) being arranged at a location between two manufacturing units (30; 31; 32; 33; 34; 35) to transfer the reusable molds from one manufacturing unit to the other manufacturing unit.
Abstract:
A method for avoiding the entrapment of air bubbles (5) in a lens forming material, in particular in a low viscosity lens forming material, in an ophthalmic lens manufacturing process using mold halves (2; 3) each having a lens forming surface (21; 31) comprises electrostatically charging a predetermined portion of the lens forming surface (21; 31) of the mold half (2; 3) prior to the predetermined portion of the lens forming surface (21; 31) coming into contact with the lens forming material (4).
Abstract:
Described herein is a cost-effective and time-efficient method for making UV-absorbing contact lenses. In contrast to the conventional method for making UV-absorbing contact lenses which involves copolymerizing a lens forming composition including a UV-absorbing vinylic monomer, a method of the invention involves dipping a contact lens in a solution of UV-absorbing polymer comprising carboxyl-containing monomeric units and UV-absorbing monomeric units to form a UV-absorbing coating on the contact lens.
Abstract:
A manufacturing module (MM) for contact lenses comprises a plurality of manufacturing stations (300, 301, 302, 310, 320, 321, 322, 330, 331, 340, 341, 342, 350, 351, 352) arranged in a closed loop and a plurality of lens mold carriers (1, 2) which are transported through the manufacturing stations. Each lens mold carrier (1, 2) comprises a frame (10, 20) having a predetermined number of mounting sites (100, 200) arranged along the frame. Each lens mold carrier (1, 2) further comprises a predetermined number of molds (112, 212) removably mounted to the frame (10, 20) at the mounting sites (100, 200), the molds being reusable male or female molds (212, 112). Two lens mold carriers (1, 2) are assigned to each other to form a pair, so that upon mating the pair of lens mold carriers (1, 2) the male and female molds (212, 112) are mated to form mold cavities defining the shape of the lenses. The manufacturing stations comprise a mold changing station (300, 301, 302) configured to be capable of removing a mold from its mounting site (100, 200) and mounting a different mold at the said mounting site (100, 200), or configured to change the rotational position of a mold (112, 212) mounted to the frame (10, 20), or both.