Antireflective coating compositions and methods for depositing such coatings

Abstract

Coating compositions, and methods for depositing them on the surface of an article to produce an antireflection coating, are disclosed. In one embodiment, the coating composition includes a (meth)acrylate-functional silicon alkoxide, silica particles, a (meth)acrylate monomer, an epoxy(meth)acrylate oligomer, a photoinitiator, a solvent, an acid, and water. The relative amounts of these constituents are controlled such that, when the coating composition is deposited onto the surface of an article and cured, it has a refractive index less than about 1.60 at a wavelength of 510 nm. In another embodiment, the coating composition includes an organo-metallic compound other than an organo-metallic compound of silicon, an epoxy-functional silicon alkoxide, a non-epoxy-functional silicon alkoxide, a curing agent compatible with epoxy-functional molecules, a solvent, an inorganic acid, and water. The relative amounts of these constituents are controlled such that, when the coating composition is deposited onto the surface of an article and cured, it has a refractive index greater than about 1.70 at a wavelength of 510 nm. The coating compositions are deposited in a process that produces an antireflection coating in less than 90 minutes of processing time.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] Priority is claimed from co-pending U.S. Provisional Patent Application Ser. No. 60 / 680,079, filed May 11, 2005, and Ser. No. 60 / 701,545, filed Jul. 22, 2005, which are incorporated herein by reference.BACKGROUND OF THE INVENTION [0002] This invention relates generally to antireflective coating compositions and to methods for depositing such compositions onto articles, especially transparent articles. [0003] Antireflection coatings on transparent articles reduce the reflectance of visible light from the articles and enhance the transmission of such light into, or through, the articles. When the articles are used as cover plates for display instruments, these coatings enhance the brightness, contrast, and readability of the displayed information, for a variety of lighting conditions. Optical articles such as ophthalmic lenses frequently are coated with antireflective coatings to decrease the level of reflected light and thereby increase ...

AI Technical Summary

Benefits of technology

[0006] The present invention resides in an improved antireflection coating compositions and for an improved process for depositing such coating compositions onto articles, especially transparent articles, in a variety of sizes and configurations, with reduced cost and with reduced susceptibility to mechanical damage.

Problems solved by technology

Although various antireflection coatings have been generally effective in providing reduced reflectivity over the visible spectrum, the coatings are not considered to have been entirely satisfactory for use in many applications.

For example, some of the coatings are highly susceptible to mechanical damage from abrasion and exhibit poor adhesion to the underlying substrate.

Moreover, some of the processes used for depositing such coatings, including electron beam deposition, reactive plasma sputtering, and ion-assisted deposition, are relatively expensive to implement.

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