摘要:
In a method of drying molds or mold parts for the manufacture of optical lenses, in particular ophthalmic lenses and especially contact lenses, the mold or mold part to be dried is exposed to drying air. For this purpose, humid pressurized air (T) is used to which the mold or mold part is exposed.
摘要:
In a method of drying molds or mold parts for the manufacture of optical lenses, in particular ophthalmic lenses and especially contact lenses, the mold or mold part to be dried is exposed to drying air. For this purpose, humid pressurized air (T) is used to which the mold or mold part is exposed.
摘要:
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.
摘要:
The invention is concerned with the problem that with known plastic casting molds, especially those of polypropylene, the lenses produced with these molds have a slippery surface. The invention solves this problem through the use of polymers which are notable for their very low oxygen permeability.
摘要:
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.
摘要:
The invention is concerned with the problem that with known plastic casting moulds, especially those of polypropylene, the lenses produced with these moulds have a slippery surface. The invention solves this problem through the use of polymers which are notable for their very low oxygen permeability.
摘要:
A process of dosing a starting material (SM) for optical lenses, into a female mould half (2), comprises the steps of: positioning a dosing tip (1) at a start position (P2) above the female mould half (2) and close to the edge of or laterally outside that portion (20) defining the lens-shaping surface, creating a continuous flow of starting material (SM) through the dosing tip (1) into the female mould half (2), moving the dosing tip (1) from the start position (P2) towards an end position (P3) in the region of the centre of the female mould half (2) once the starting material (SM) has contacted the surface (21) of the female mould half (2) with the dosing tip (1) being in the start position (P2), wherein the continuous flow of starting material (SM) through the dosing tip (1) and the movement of the dosing tip (1) from the start position (P2) to its end position (P3) are controlled such, that a continuous bead (B) of starting material (SM) is deposited on the surface (21) of the female mould half (2) and that the essential part of the overall volume of starting material (SM) dosed into the female mould half (2) is deposited within the female mould half (2) with the dosing tip (1) being in the end position (P3).
摘要:
The invention is concerned with the problem that with known plastic casting moulds, especially those of polypropylene, the lenses produced with these moulds have a slippery surface. The invention solves this problem through the use of polymers which are notable for their very low oxygen permeability.
摘要:
The invention is concerned with the problem that with known plastic casting moulds, especially those of polypropylene, the lenses produced with these moulds have a slippery surface. The invention solves this problem through the use of polymers which are notable for their very low oxygen permeability.
摘要:
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.