Injection overmolding with heat/cool cycling for making optical lenses using 3D-printed functional wafers

Patent metadata

Field	Value
Publication number	US-12226968-B2
Application number	US-202017623692-A
Country	US
Kind code	B2
Filing date	Jul 1, 2020
Priority date	Jul 2, 2019
Publication date	Feb 18, 2025
Grant date	Feb 18, 2025

Abstract

Disclosed herein is an injection molding method for making optical thermoplastic lenses using 3D—printed functional wafers. The method employs a variable injection molding cavity temperature that is heated to at least wafer Tg—10° C.

First claim

The invention claimed is:

1. A method for producing an optical article, the method comprising over-molding an additive manufactured functional wafer having a functional wafer glass transition temperature onto a convex surface of a base lens to produce an ophthalmic lens, wherein the over-molding comprises:
affixing the functional wafer to a concave surface of an injection molding cavity;
filling the injection molding cavity with molten base lens material; and
raising the injection molding cavity temperature from a first temperature to a second temperature that is at least 10° C. less than the functional wafer glass transition temperature and up to and including 5° C. above the functional wafer glass transition temperature, such that T g,wafer +5° C.≥T cavity ≥T g,wafer −10° C.

2. The method of claim 1 , wherein the over-molding viscoelastically deforms the functional wafer.

3. The method of claim 2 , wherein the viscoelastic deformation templates the texture of the concave surface of the mold cavity onto the convex surface of the functional wafer.

4. The method of claim 3 , wherein a templating produces an ophthalmic lens with an optically smooth convex surface having a roughness less than 20 nm RMS.

5. The method of claim 1 , wherein the additive manufactured functional wafer is a wafer of non-optical quality with a surface roughness greater than 50 nm RMS.

6. The method of claim 1 , wherein the functional wafer includes at least one UV cut, blue cut, color enhancement, near infrared cut, chronocut, and/or photochromicity dye or filter.

7. The method of claim 1 , wherein the functional wafer material is selected from the group consisting of polyamides, polyester alloys, polyethylenes, polysiloxanes, polyimides, polyurethanes, polypropylenes, polyetheretherketones, polyetherarylketones, perfluoroalkoxys, polychloro-trifluoroethylenes, poly(meth)acrylate, polyethyl(meth)acrylate, polybutyl(meth)acrylate, polyisobutyl(meth)acrylate, polythiourethanes, polycarbonates (PC), polyallylics, polyphenylene sulfides, polyvinyls, polyarylenes, polyoxides, polysulfones, fluorinated ethylene propylenes, polytetrafluoroethylenes, ethylene-tetrafluoroethylenes, polyvinylidene fluorides, ethylene-chlorortifluoroethylenes, polystyrenes, polyacrylonitriles, polyetherimides, polypentenes, cellulose triacetate, and copolymers, derivatives, and mixtures thereof.

8. The method of claim 1 , wherein the first temperature ranges from room temperature to 10° C. below the functional wafer glass transition temperature.

Assignees

• Essilor Int

Inventors

• Shan Haifeng
• Jallouli Aref
• Chiu Hao-Wen

Classifications

• B29L2011/0016

  Lenses · CPC title

• B29K2995/0073

  smooth · CPC title

• B29K2995/0031

  Refractive · CPC title

• B29C45/14778

  the article consisting of a material with particular properties, e.g. porous, brittle · CPC title

• B29C45/1418

  the inserts being deformed or preformed, e.g. by the injection pressure · CPC title