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Bleaching

Materials and Supplies

BLEACHING

Each fiber has its characteristic color. 
Some methods of fiber prep will lighten the color. 

Japan - when hanging stripped fibers to dry outside they get bleached by the sun 

End of the 18th century - chlorine was used. 
Chlorine can seriously degrade cellulose fibers and change the ph.  The paper will become yellowed and brittle as it ages. 

The best safest chemical bleaching way to lighten the fibers natural color 
. steep fibers in dilute solution of hydrogen peroxide for several days after cooking. 
. optimal bleaching at ph 9.0-9.5 

Hydrogen peroxide does not leave a harmful residue but you must be sure to wash thoroughly to reduce ph to 7.0.