Method and apparatus for applying a coating to an ophthalmic lens

Abstract

The invention provide a method for applying a coating to an ophthalmic lens or a mold for making the ophthalmic lens or a medical device other than ophthalmic lens. The method comprises spraying at least one layer of a coating liquid onto an ophthalmic lens using a spraying process selected from the group consisting of an air-assisted atomization and dispensing process, an ultrasonic-assisted atomization and dispensing process, a piezoelectric assisted atomization and dispensing process, an electro-mechanical jet printing process, a piezo-electric jet printing process, a piezo-electric with hydrostatic pressure jet printing process, and a thermal jet printing process. The coating can comprise a property / functionality pattern or a color image or combination of both.

Description

[0001] This invention generally relates to a method of treating polymeric materials, such as ophthalmic lenses and medical devices. In particular, this invention is directed to a coating / printing method and apparatus for modifying the surface properties and / or functions of an ophthalmic lens or a medical device. BACKGROUND [0002] Many devices used in biomedical applications require that the bulk of the device have one property, while the surface of the device has another property. For example, contact lenses may have high oxygen permeability through the lens to maintain good corneal health. However, materials that exhibit exceptionally high oxygen permeability (e.g. polysiloxanes) are typically hydrophobic and will adhere to the eye. Thus, a contact lens generally has a core or bulk material that is highly oxygen permeable and hydrophobic, and a surface that has been treated or coated to increase hydrophilic properties, thereby allowing the lens to freely move on the eye without adh...

AI Technical Summary

Benefits of technology

[0013] Another objective of the invention is to provide an ophthalmic lens the surface of which is modified to increase

Problems solved by technology

However, materials that exhibit exceptionally high oxygen permeability (e.g. polysiloxanes) are typically hydrophobic and will adhere to the eye.

Some plasma treatment processes, however, require a significant monetary investment in certain equipment.

Thus, lenses that are wet from prior hydration or extraction processes must be dried, thereby imposing added costs of obtaining drying equipment, as well as added time in the overall lens production process.

However, these methods require a complex and time-consuming pretreatment of the substrate to produce a surface having a highly charged, hydrophilic, or hydrophobic nature in order to bind the polycationic or polyanionic material to the glass substrate.

For example, this current LbL deposition technique is not capable of applying two or more materials having different properties / functionalities onto biomaterials, such as contact lenses, to form property / functionality patterns on the surfaces of the biomaterials.

Another example is that this current LbL deposition technique is not capable of applying asymmetrically one coating material to one of the two surfaces of an intraocular lens and another different coating material to the other surface of that intraocular lens.

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