Graphic Design & Printing Technologywithout drying. These inks dry quickly on paper and are commonly used in
small sheet-fed presses.
Web-offset heat-set ink:- Web-offset heatset ink requires the application of
high temperature immediately after the ink film reaches the substrate. Heat-set
inks are inks that dry when hot air accelerates the evaporation of solvents.
Web-offset cold-set ink:- They are inks that are used to print on absorbent paper
inorder to dry properly.
News ink:- They are generally thin and fluid ink made of mineral oil and carbon
black which dry by absorption.
Magnetic ink:- Magnetic inks are designed primarily for printing products such
as cheques, bank notes and business forms that are sorted and read electronically.
Invisible ink:- It is a security type of ink which print clear, but they show up as
fluorescent blue or yellow when placed under back light.
Opaque inks:- These inks are required for printing on dark coloured papers, to
hide the colour of the underlying substrate and to prevent the colour of the
substrate from influencing the ink colour.
Waterless offset inks:-They are formulated for offset presses that do not use
dampening solutions.
Fluorescent ink:- These inks are made with fluorescent pigments that transfom
UV light into visible light.
Metallic ink:- They are made with small metal flakes or particles (Aluminium
for silver and Bronze or Brass for gold).
Over print varnishes:- They are transparent coating applied over ink. They
are used to protect the printed surface from moisture, abrasion or other potential
sources of damage. They are also applied to create gloss, matt or satin finish.
Soy ink:- Soy ink use oil extracted from soyabean as part of vehicle. They are
bio-degradable inks which replace petroleum used oils with vegetables oils
and clearly volatile organic levels in the press room.
Chemicals used in Printing
Dampening solution
Dampening solutions are mixtures of water and other chemicals distributed by
the dampening system of offset press. Most dampening solutions are made up
with basic ingredients such as water, acid, gum arabic, wetting agents, corrosion
inhibitors, anti foaming agents, fungicides and drying stimulators.