OPTICAL WHITENERS

                  All  types  of textile fibres, natural or synthetic,  do  not  appear perfectly white but exhibit a yellow tinge because of  the presence of certain coloured impurities which absorb some of  the incident  light in the blue end of the spectrum.   Three  methods are  available to remove the yellow tinge.  The first one is  the destruction  of the colouring matter by bleaching  agents.   This method  is  invariably  used  to remove  most  of  the  colouring impurities  from  the fibre but it is not possible  to  eliminate totally  the  slight yellowish tinge without degradation  of  the  fibre  itself.   The  second method employs the  use  of  blueing agents  on  the  bleached  fabric.   These  agents  correct   the yellowness  of  the  fabric by absorption of  yellowness  of  the fabric by absorption of yellow light by the applied blue pigment.

In this case the yellowish white fabric acquires a greyish  white appearance.

Project Report Covers:

Introduction
Uses and Applications
Properties
Market Survey with future aspects
Present Manufacturers
B.I.S. Specifications
Manufacturing Process with Formulae
Cost Economics with Profitability Analysis
Capacity
Land & Building Requirements with Rates
List & Details of Plant and Machinery with their Costs
Raw Materials
Details/List and Costs
Power & Water Requirements
Labour/Staff Requirements
Utilities and Overheads
Total Capital Investment
Turnover
Cost of Production
Break Even Point
Profitability
Land Man Ratio
Suppliers of Plant & Machineries and Raw Materials.