What is ink

Ink is a fluid or paste having an intense colour. Inks comprise a pigment or dye as the chromophore dissolved or dispersed in a liquid called the vehicle. 

The first inks for writing comprised soot suspended in water. 

Modem writing inks usually contain ferrous sulphate, together with a small amount of mineral organic acid. The resulting solution is light bluish black, and results in 

India ink is stabilized to prevent sedimentation by adding substances such as shellac in borax solution, soap, gelatine, glue, gum arabic, and dextrin. 

To make the written image darker and more legible at the outset, additional dyes are added to the mixture. Modem coloured inks, and washable inks, contain a soluble synthetic dye as the sole chromophore, ensuring s is large and obviating the requirement for overwriting. 

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What is ink Common bluing Galvanized iron Iron rust ... 

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