tzAvoRiteā„  Information

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tzAvoRite is the superior anti-reflective coating and topcoat produced by Opticote, Inc. of Franklin Park, IL. It’s a culmination of research brought together and integrated by the scientists, engineers, and management of one of the largest vacuum coating companies in the ophthalmic industry. Research was further enhanced by chemical engineers and experts in surface physics from around the world. The final product is a component of the finest quality lenses from the world's best manufacturers, a hardcoating technique that is unparalleled in it’s quality, an anti-reflective stack that provides superior light transmission and a topcoat that repels water, oil, dust and dirt and has an extended life and extreme durability.

Using the proper materials, and preparation of the lens surface, are critical to the quality of the final product. Lenses must be top quality, lab preparation is instrumental, and then Opticote does the magic of making the most durable AR coating known.

Desire for Durability


To understand the need for a hardcoated lens when using an anti-reflective coating, think about how a sheet of tin foil might react when being abused on a pillow, or alternatively, how it may react to being on a smooth counter top. It the sheet of foil is put on top of a soft pillow and then a finger is dragged along the foil, it will bend, dent and possibly tear. That's because the material under the foil is so soft. If the same foil is put on top of a smooth counter and a finger is dragged across it, there is no damage to the foil.

The same is true of an AR stack. If this incredibly thin stack is put on a soft substrate, it will bend, dent, scratch and possibly break down altogether. On the other hand, if the AR stack is put on a hard and durable surface it's going to be resistant to almost every kind of pressure or contusion.

An extremely hard coating is the key to manufacturing an anti-reflective lens that is durable.

Substrates


Not every ophthalmic lens available in the United States can be coated with tzAvoRite. Although most substrates (CR-39, polycarbonate, mid-index, 1.60, 1.67, and Trivex) are acceptable, the best lenses are those produced by reputable and well-known manufacturers that DO NOT use any kind of ultra violet curing during their production process. While Opticote can accept hardcoated or non-hardcoated lenses, the preference is non-hardcoated, which will allow for a more refined processing.

Laboratories should follow these procedures when sending lenses to Opticote for tzAvoRite:

• Lenses must be uncut and must be round
• Diameter is not to exceed 78mm
• No knife edges
• No lined bifocals, i.e., flat top bifocal, trifocal, or executive
• Only approved lenses can be coated and the lens boxtop should accompany the order
• DO NOT put any kind of backside hardcoating on the lenses.
• Lenses not-hardcoated on the front surface are ideal
• All residue must be completely cleaned from lenses
• Lenses must be thoroughly cleaned in an ultrasonic cleaner, cleaned again with alcohol, and then allowed to air dry
• All of these steps are taken to avoid any contamination of the lenses which would affect adhesion.

Arrival at Opticote


To prepare for tzAvoRite, Opticote made a huge investment in building a certified clean room with positive air flow. Operators are required to wear sterile shoes, gowns and headdress, and only authorized personnel are allowed to enter this special area. To further reduce the chances of contamination, the processing line is a positive pressure sealed unit consisting of 6 cleaning and dipping stations and 2 infra-red ovens. All chemicals and exact processes are proprietary.

Lenses are received, logged in, inspected, and then put through an intense cleaning process. Once this is completed, the lenses are inspected again, put in special racks, and prepared for the real cleaning!

Air ionization is the first step, which eliminates any residual dust or grit. Then the racks go into two separate detergent tanks that have a high pH chemical for etching. The next step is rinsing, followed by immersion in a neutralizer tank which removes any semblance of residual material. At this point the front and back of the lenses have become a neutral surface. Another rinse and then the final cleaning step is into de-ionized water that is so pure it could conceivably be injected directly into your bloodstream without any negative effect! Only now are the lenses are ready to be hardcoated.

After the intense cleaning, robotics take over and eliminate any chance of human error. Lenses are air dried and then are dipped in a primer that could be compared to a paint primer used on metal. Just as the paint primer ensures that the paint stays on the metal, the lens primer ensures that the hardcoat stays on the lens. This primer is a cohesive system with a molecular structure that promotes adhesion. Curing of the primer is done in a self-contained infra-red oven. When dry, the lenses are dipped for a pre-determined time in the proprietary hardcoating and then cured to a tack-free dry in another self-contained infra-red oven. At this stage the racks are removed from the robotic system and the lenses are put into a conventional oven where they are cured at a high temperature for over 4 hours.

This entire process, all of which is prior to anti-reflective coating, takes almost 7 hours and makes the lens surface so hard that it's virtually scratch-proof!

Vacuum Coating Stacks


The lenses are now taken out of the cleaning and hardcoating racks, cleaned one more time, and re-racked for anti-reflective coating. Once in the AR chamber, 7 proprietary layers of silicon dioxide and other rare earth materials are put on the surface. This 2 hour process is followed by one more layer that is extremely critical for the durability and care of the lenses when they're worn by a patient.

This last layer is a hydrophobic/oleophobic coating applied in yet another vacuum chamber. This final coating makes the lenses very slick and actually repels water, skin oils and dust. And environmental testing indicates it will last for more than two years!

tzAvoRite lenses are now ready to be dispensed. Production has taken approximately 10 hours and the result is an incomparable consumer product. They are so hard that it's almost impossible to scratch them. The AR stack increases light transmittance to almost 100% and virtually eliminates reflections. The final topcoat means the consumer can wear them comfortably without fear of an extreme buildup of oils and dirt, and when dirty, can clean them easily.

tzAvoRite, the finest materials, the finest processing, and the finest quality combining to create a truly symbiotic relationship of the components!