title: Engineering of cotton fabrics for maximizing in vitro ultraviolet radiation protection.
abstract: BACKGROUND
  Cotton fabrics used in summer do not often provide good protection against solar ultraviolet (UV) radiation. Heavy cotton fabrics can provide good protection against UV radiation. However, heavy fabrics are not good from a comfort point of view as the air permeability and moisture vapour transmission rate is very low.
  
  
  OBJECTIVE
  To engineer cotton fabrics which will provide maximum UV protection without sacrificing the minimum requirement of air permeability and thermal resistance for a particular climatic condition.
  
  
  METHODS
  Sixteen plain and sixteen twill woven fabrics were manufactured using different cotton yarn count and picks per cm. Nonlinear regression models were developed to relate the fabric parameters with the ultraviolet protection factor (UPF), air permeability and thermal resistance. Optimization problems were formulated for UPF maximization keeping air permeability and thermal resistance as constraints. Optimization problems were solved to find out the values of yarn count and picks per cm. New fabrics were then woven using optimized combinations of yarn count and picks per cm, and error assessment between the target and the achieved fabric properties was performed.
  
  
  RESULTS
  The target, optimized and achieved fabric properties are showing good association. When air permeability requirement is high, the engineered cotton fabric can provide good UV protection (UPF > 15). When the air permeability requirement is low, the engineered cotton fabric can provide excellent UV protection (UPF > 40).
  
  
  CONCLUSIONS
  It is possible to engineer cotton fabrics to maximize the UV protection without compromising with the comfort properties.
authors.affiliation: Department of Textile Technology, Indian Institute of Technology Delhi, New Delhi, India. abhitextile@rediffmail.com
authors.forename: Abhijit
authors.initials: A
authors.lastname: Majumdar
authors.forename: Vijay Kumar
authors.initials: VK
authors.lastname: Kothari
authors.forename: Achintya Kumar
authors.initials: AK
authors.lastname: Mondal
mesh_terms: D032561:Cotton Fiber; D006801:Humans; D010539:Permeability; D011835:Radiation Protection; D013473:Sunscreening Agents; D014466:Ultraviolet Rays
chemical_list: D013473:Sunscreening Agents