Fibers and fibrous moldings using the same

Fibers comprising a propylene-ethylene copolymer consisting of 0.01 to 15 mol % of ethylene units and 99.99 to 85 mol % of propylene units as at least one component, wherein:

• a) a chain constitution of the copolymer found by means of nuclear magnetic resonance spectrum has the following relationships:
• a-1) in three monomers chain units (triad) in main chains of the copolymer, there is a relationship according to formula (I):
• 0.0070.times.C2-0.0020.ltoreq.PEP.ltoreq.0.0070.times.C2+0.0130(I)
• between a fraction of propylene unit--ethylene unit--propylene unit chain (PEP) and a total content of ethylene unit (C2), when PEP is positive, and
• a-2) in three monomer chain units (triad) in main chains of the copolymer, there is a relationship of formula (II):
• 0.ltoreq.EEE.ltoreq.0.00033.times.C2+0.0010 (II)
• between a fraction of three continuous ethylene units chain (EEE) and a total content of ethylene unit (C2), as well as
• a-3) a ratio of total .alpha.,.beta.-methylene carbon atoms (N.alpha..beta.) to total propylene units is within a range of 0 to 1.2 mol %,
• b) a weight average molecular weight (Mw) is 50,000 to 1,500,000, as well as
• c) a ratio (Mw/Mn) of a weight average molecular weight (Mw) to a number average molecular weight (Mn) is 1.2 to 3.8.