| 摘要 |
<p>PURPOSE:To obtain a pellicle having high light transmittance and excellent air-blow resistance and operability by using a fluorine-base polymer having specified substituents as a low refractive index material for an antireflection layer. CONSTITUTION:The low refractive index layer for an antireflection layer consists of an amorphous perfluoropolymer having carbonylcontg. groups in side chains. This amorphous perfluoropolymer having carbonyl-contg. groups in side chains used for the dustproof cover of a mask is expressed by the formula. In the formula, Rfo is a perfluoroether unit, R1 is a perfluoroalkyl group or its partially substituted group of 1-15 carbon number, m1 is 0 or positive integer and m2 is a positive integer satisfying m2/(m1+m2)=0.001 to 1.0, R2 is a perfluoroalkylene group of 1-10 carbon number, bivalent perfluoroether group of 2-30 carbon number, etc., X is ORa, NRb or Rc, wherein Ra, Rb, Rc are hydrogen atoms or hydrocarbon groups of 1-10 carbon number.</p> |
