Patent ID: 8409481
Filing Date: 2013-04-02
Classification: B29C,B29D

Abstract:
1. A method of manufacture of an implantable planar/convex, biconvex, planar/concave or convex/concave lens made from a liquid polymer precursor, which is capable of a transition into a clear, solid polymer state by polymerization and/or cross-linking in an open mold, the mold having a functional shaping inner surface that is separated from the remaining surface of the open mold by a peripheral circular sharp edge with an intermediate circular edge having the shape of a circle lying in the plane parallel to the plane of the peripheral sharp edge into a transitional open cylindrical or frustum-of-a-cone cavity delineated between the peripheral sharp edge and the intermediate circular edge, wherein the transitional open cylinder or frustrum-of-a-cone cavity defines a planar surface at an angle α2 less than or equal to 90°, the functional shaping inner surface being unwettable or incompletely wettable by the liquid precursor, the method comprising the steps of: a) metering the liquid polymer precursor into the open mold in an amount at which an edge of the surface of the liquid precursor contacting an inner surface of the open mold is located under the peripheral circular sharp edge of the open mold or reaches a peripheral circular sharp edge and at least a part of the surface of the liquid polymer precursor will protrude above the plane defined by the peripheral circular sharp edge of the open mold, or at least a part of the surface of the liquid precursor lies in this plane or the whole surface of the liquid polymer precursor lies below this plane, while in this case the liquid polymer precursor will be metered into the open mold in the amount, which will always be higher than the amount of the liquid polymer precursor needed to obtain a contact eye lens of the same diameter; b) rotating the open mold, which contains the liquid polymer precursor, around its vertical axis at a speed at which the liquid polymer precursor displaces in the open mold to the extent that the surface of the liquid polymer precursor overtops the plane defined by the peripheral circular sharp edge of the open mold at least at proximity of the peripheral circular sharp edge without draining away from the open mold via over the peripheral circular sharp edge such that an outer edge of the implantable lens has a smooth curvature at or above the peripheral circular sharp edge; c) exposing the liquid polymer precursor to solidifying conditions, under which it will be able of transformation into a state of a clear, solid polymer by polymerization and/or cross-linking; d) and the open mold continues to be rotated under the said solidifying conditions at the said speed at least until the time, when the edge of the surface of the polymerized and/or cross-linked liquid polymer precursor reaches the peripheral circular sharp edge of the open mold even if the rotation of the mold was slowed down or stopped; e) then optionally slowing down the rotation of the open mold or stopping the rotation of the open mold; f) and the exposure of the contents of the open form to the said solidifying conditions continues at least until the said transition is attained; and g) whereupon the implantable lens is removed from the open mold.