Reusable lens molds and methods of use thereof

Patent metadata

Field	Value
Publication number	US-10328645-B2
Application number	US-201615347081-A
Country	US
Kind code	B2
Filing date	Nov 9, 2016
Priority date	Dec 17, 2015
Publication date	Jun 25, 2019
Grant date	Jun 25, 2019

Abstract

The present invention general related to a method and a reusable mold for making a contact lens, comprising a first mold half having a first mold surface in contact with a hydrogel contact lens forming composition and a second mold half having a second mold surface in contact with the lens forming composition, wherein the first mold half and the second mold half are configured to receive each other such that a cavity is formed between the first mold surface and the second mold surface, wherein the cavity defines the shape of a contact lens to be molded, wherein the lens forming composition is polymerizable and/or crosslinkable by an actinic radiation, wherein at least one of the mold halves having an absorbing antireflective coating, wherein the reusable mold is a non-plastic mold.

First claim

What we claim is:

1. A reusable non-plastic mold for making a contact lens, comprising a first mold half having a first mold surface in contact with a hydrogel contact lens forming composition and a second mold half having a second mold surface in contact with the lens forming composition, wherein the first mold half and the second mold half are configured to receive each other such that a cavity is formed between the first mold surface and the second mold surface, wherein the cavity defines the shape of a contact lens to be molded, wherein the lens forming composition is polymerizable and/or crosslinkable by UV, wherein the first mold half facing the source of UV includes a peripheral region which defines the edge of the contact lens, wherein the peripheral region has a mask to block UV, wherein the back side, non-optical surface of the second mold half has an absorbing antireflective coating.

2. The reusable mold for making a contact lens of claim 1 , wherein the absorbing antireflective coating having a less than 2 percent reflection between 380 nm to 460 nm in near normal incident.

3. The reusable mold for making a contact lens of claim 1 , wherein the absorbing antireflective coating comprising at least two layers of coating.

4. The reusable mold for making a contact lens of claim 3 , wherein the absorbing antireflective coating comprising at least three layers of coating.

5. The reusable mold for making a contact lens of claim 4 , wherein the absorbing antireflective coating comprising at least two layers of a transition metal nitride.

6. The reusable mold for making a contact lens of claim 5 , wherein the transition metal nitride layers comprise a material selected from the group consisting of titanium nitride, zirconium nitride, hafnium nitride, vanadium nitride, niobium nitride, tantalum nitride and chromium nitride.

7. A method for producing a contact lens, comprising the steps of:
(1) providing a non-plastic contact lens mold, wherein the mold comprising a first mold half having a first mold and a second mold half having a second mold surface, wherein the first mold half and the second mold half are configured to receive each other such that a cavity is formed between the first mold surface and the second mold surface, wherein the cavity defines the shape of a contact lens to be molded, wherein the first mold half facing the source of UV includes a peripheral region which defines the edge of the contact lens, wherein the peripheral region has a mask to block UV, wherein the back side, non-optical surface of the second mold half has an absorbing antireflective coating
(2) introducing a lens-forming composition into the cavity formed by the first and second molding surfaces, material, wherein the lens-forming material is crosslinkable and/or polymerizable by actinic radiation;
(3) crosslinking/polymerizing the lens-forming material in the mold to form a lens having a polymer matrix;
(4) opening the mold and removing the formed contact lens from the mold, wherein the formed contact lens has a clean lens edge without flash.

8. The method for producing a contact lens of claim 7 , wherein the absorbing antireflective coating having a less than 2 percent reflection between 380 nm to 460 nm in near normal incident.

9. The method for producing a contact lens of claim 7 , wherein the absorbing antireflective coating comprising at least two layers of coating.

10. The method for producing a contact lens of claim 8 , wherein the absorbing antireflective coating comprising at least three layers of coating.

11. The method for producing a contact lens of claim 9 , wherein the absorbing antireflective coating comprising at least two layers of a transition metal nitride.

12. The method for producing a contact lens of claim 11 , wherein the transition metal nitride layers comprise a material selected from the group consisting of titanium nitride, zirconium nitride, hafnium nitride, vanadium nitride, niobium nitride, tantalum nitride and chromium nitride.

Assignees

• Novartis Ag

Inventors

• Liu Alice Weimin
• Pi Ying

Classifications

• B29K2909/08

  Glass · CPC title

• B29D11/00134

  Curing of the contact lens material · CPC title

• B29D11/00192

  Demoulding, e.g. separating lenses from mould halves · CPC title

• B29C39/26

  Moulds or cores · CPC title

• B29L2011/0041

  Contact lenses · CPC title