Lens Tinting,

[dpwct]

I am interested in creating tinted PC lenses, with a clear stripe in the lens about 4mmx12mm (not tinted). Any suggestion on how to accomplish this in scale?

[Chris Ryser]

On polycarbonate lenses you can only tint the hard coat. Stick a heat resistant plastic tape where you want no color and tint them fast in the microwave. Not every dye will work properly under microwaves.

[LisaRayes]

Most tints use a carbon molecule that binds to a carbon molecule in plastic for its adhesion and stability. Polycarbonate chemical structure makes it resistant to this carbon binding. The best way to tint polycarbonate is to tint its scratch coating, however, historically the best scratch coats have been resistant to tinting. To overcome these limitations, manufacturing labs have recently developed scratch coats better able to absorb tints. However, in general, the best hard coat scratch protectors still make tinting polycarbonate more challenging than other materials.

[Kujiradesu]

If you can, I would use Trivex. Same impact resistance, only slightly lower index, and it tints like a dream.

[Chris Ryser]

The best way to tint polycarbonate is to tint its scratch coating, however, historically the best scratch coats have been resistant to tinting.

That is correct. Tintable Polycarbonate lenses have added tintable materials and somer brands have an uneven thickness, which will show when tinted, and some other brands will delaminate under to much heat.