The layer should provide protection against mechanical damage so as to keep the optical layer intact during its lifetime. As far as scratch resistance is concerned, we want to satisfy the following specs: weight loss should be < 2 mg per 100 cycli in the TABER test for resistance of transparent plastics to surface abrasion (ASTM D1044/D4060). In this test a circular sample is put on a Taber abraser and rotatively charged with two abrading wheels with a specific charge (250, 500 or 1000 g). Weight loss is measured after a number of cycli. Our test specs are :abrading wheels = CS10Fcharge = 250 g per wheelnumber of cycli = 100 or 1000Some values for known materials : PE 5 - 10 mg PU 1.5 mg PC 1 mg PP 4 mg. More on the following link http://www.ptli.com/testlopedia/tests/Taber_Abrasion-d1044.asp<br/>To provide this scratch resistance we are looking for a coating solution that can be applied either by spray coating, doctor blade coating or dip coating. The finished coating should be colorless and transparant and should not dissolve or swell in ethanol. The coating solution should be applied onto a surface having a surface tension of 20 dynes/cm.

Not specified