Transitions Plastic vs Poly

[LENNY]

Is Transition technology any different (application, life span, performance) in different materials.
Lets say CR-39 vs Polycarbonate?
Where can I look it up?

[Fezz]

Contact a fellow member, Jim Schafer.

He is the resident Transitions Guru!

[eyeGJ]

Maybe this will help until Jim arrives.........

http://us.transitions.com/NR/rdonlyr...GTechNotes.pdf


Ginny

[Jim Schafer]

Hi Lenny,
I hope all is well.
The Transitions VI Tech Notes should have answered any questions you may have.

The main differences between standard index (CR607) and poly are not in performance but in how we process the lens blank to make it photochromic and that part is transparent to the patient. Standard Index Transitions are imbibed and Poly along with Trivex, 1.60, 1.67 and 1.74 are all Transbonded. Again, regardless of the material, the lifetime, activation rates, darkness and fade back are the same.

Jim

[mshimp]

what is the diference between imbibed and transbonded? Or better said describe the process of being imbibed and trasbonded?

[Jim Schafer]

Transitions Optical uses two technologies to make lenses photochromic, Imbibition and Transbonding. Imbibition relies on the lens substrate to be acceptable to dye migration and for the substrate to be a good host for the dyes. While some lens monomers have proved to be good host materials, several including CR39, had to be modified (hence CR607 for Transitions VI branded lenses) to allow the photochromic dyes to exhibit their performance potential. Other materials including polycarbonate and high index are not amenable to the imbibition process, so Transitions developed the Transbonding process that permits these substrates which cannot be imbibed to be made photochromic.

Imbibition is a propietary patented process developed and commercially introduced by Transitions Optical in 1991. With Imbibition, the photochromic compounds are driven into the front surface of the lens. The compounds are permanently imbedded into the surface to a uniform depth of 150-200 microns, about 20 times deeper than a lab tint. The compounds becaome part of the lens and cannot be scratched or peeled off.

For lens materials that are poor hosts for imbibing technology, Transitions Optical developed the propietary Transbonding process. In Transbonding these lens materials receive propietary surface treatments and a series of ophthalmic grade layers, which provide adhesion, scratch resistance and optical purity.

I cannot go any deeper than these top line descriptions of our processes.

Jim

[mshimp]

Jim, Thanks for the info.
mike

[LENNY]

Thanks a lot!
Are there any other colors in the works?

[DragonLensmanWV]

Thanks a lot!
Are there any other colors in the works?

Yeah, I get requests for plaid Transitions all the time!!