To speed the reaction and help the dye fix to the fiber, an alkali is used as a catalyst. For Fiber Reactive Procion Dyes the alkali used is Soda Ash. The alkali strips hydrogen atoms off of the cellulose molecules so that the dye can easily form the covalent bond with the oxygen in the hydroxyl (-OH) groups.he process in this case is âsubtractive,â since the pigments subtract or absorb some of the wavelengths of light. With transparent dyes, like our Fiber Reactive Dyes that we use for Tie-Dye, Cyan (blue-green), Magenta (red-violet), and Yellow and are called subtractive primaries, or primary colors.
EAN is the abbreviation of European Article Numbering. EAN-13 is a relatively common general terminal product barcode protocols and standards, mainly used in supermarkets and other retail.he left one number call prefix, in the EAN-13 commodity barcode the prefix is said by barcode character, and the prfix is not included in the data symbols in the left.
An EAD is an Employment Authorization Document issued to foreign workers who fall into certain immigrant and nonimmigrant categories - for instance, for those who have filed a Form I-485 Application to Register for Permanent Residence or Adjust Status.