GC 3460 FINAL QUESTIONS AND
VERIFIED ANSWERS
Paper Attributes - ANSWER-grain, tear strength, folding strength, burst strength, pick strength, weight,
flexibility, moisture content, size, whiteness, brightness, texture, opacity, holdout, etc
How is brightness imparted on paper? - ANSWER-bleaching fibers, adding OBAs (fluorescing pigments)
How is strength imparted on paper? - ANSWER-beating the fibers
Steps of the Modern Paper-making Process - ANSWER-1. Felling
2. Debarking
3. Chipping
4. Pulping
5. Mixing
6. Forming the Web
7. Pressing
8. Drying
Coated Paper Properties - ANSWER-ink pigment sits on top of the sheet; lower strength
Uncoated Paper Properties - ANSWER-can be smooth or textured; glare free for reading; stronger and
more opaque
Pigment - ANSWER-solid component
Resins - ANSWER-vehicle; binds pigments to the substrate; dissolved by solvent
Solvents - ANSWER-vehicle; dissolve resins to add flow; provides flow and adhesion
Organic Pigments - ANSWER-made in labs using carbon chemistry; transparent inks with varying
lightfastness (usually poor)
Inorganic Pigments - ANSWER-ground minerals, generally dry pigments; opaque; offers great
lightfastness
Drying/Curing Mechanisms of Ink - ANSWER-evaporation, absorption, oxidation, heat set, energy cured
Energy Cured Inks - ANSWER-100% solids; UV and electron beams; nothing evaporates, everything stays
and hardens
Conventional Inks - ANSWER-water based and solvent; made of 50% solids (resin, pigment, wax) and 50%
solvent; solvents evaporate away to dry ink, leaving behind resins to harden
Ink Additives - ANSWER-reducers, retarders, surfactants, waxes, plasticizers, defoamers
Reducers - ANSWER-adds solvents to the ink, changes viscosity
Retarders - ANSWER-slows drying
Surfactants - ANSWER-increase wettability by changing the surface tension of ink
Waxes - ANSWER-improve rub resistance, slip, and water resistance
Plasticizers - ANSWER-impart flexibility to brittle resins; impart gloss, adhesion, and protect against cold
temps (brittleness)
Defoamers - ANSWER-reduces foam or bubbles that can interfere with proper distribution of dampening
solution
Paste Ink - ANSWER-Ink with high viscosity; requires reduction in shear; litho and screen
Liquid Ink - ANSWER-low viscosity; must be rewet between impressions; flexo and gravure
Viscosity - ANSWER-resistance to flow; controlled by solvent
pH of Ink - ANSWER-if too low, ink will body up or become more viscous; if too high, poor water
resistance and unstable
How do we control pH? - ANSWER-amines are added to raise pH and evaporated to lower pH
Press-side Additives - ANSWER-reducers, extenders, retarders, surfactants
Extender - ANSWER-ink without pigment, allows for adjustment of color strength
VERIFIED ANSWERS
Paper Attributes - ANSWER-grain, tear strength, folding strength, burst strength, pick strength, weight,
flexibility, moisture content, size, whiteness, brightness, texture, opacity, holdout, etc
How is brightness imparted on paper? - ANSWER-bleaching fibers, adding OBAs (fluorescing pigments)
How is strength imparted on paper? - ANSWER-beating the fibers
Steps of the Modern Paper-making Process - ANSWER-1. Felling
2. Debarking
3. Chipping
4. Pulping
5. Mixing
6. Forming the Web
7. Pressing
8. Drying
Coated Paper Properties - ANSWER-ink pigment sits on top of the sheet; lower strength
Uncoated Paper Properties - ANSWER-can be smooth or textured; glare free for reading; stronger and
more opaque
Pigment - ANSWER-solid component
Resins - ANSWER-vehicle; binds pigments to the substrate; dissolved by solvent
Solvents - ANSWER-vehicle; dissolve resins to add flow; provides flow and adhesion
Organic Pigments - ANSWER-made in labs using carbon chemistry; transparent inks with varying
lightfastness (usually poor)
Inorganic Pigments - ANSWER-ground minerals, generally dry pigments; opaque; offers great
lightfastness
Drying/Curing Mechanisms of Ink - ANSWER-evaporation, absorption, oxidation, heat set, energy cured
Energy Cured Inks - ANSWER-100% solids; UV and electron beams; nothing evaporates, everything stays
and hardens
Conventional Inks - ANSWER-water based and solvent; made of 50% solids (resin, pigment, wax) and 50%
solvent; solvents evaporate away to dry ink, leaving behind resins to harden
Ink Additives - ANSWER-reducers, retarders, surfactants, waxes, plasticizers, defoamers
Reducers - ANSWER-adds solvents to the ink, changes viscosity
Retarders - ANSWER-slows drying
Surfactants - ANSWER-increase wettability by changing the surface tension of ink
Waxes - ANSWER-improve rub resistance, slip, and water resistance
Plasticizers - ANSWER-impart flexibility to brittle resins; impart gloss, adhesion, and protect against cold
temps (brittleness)
Defoamers - ANSWER-reduces foam or bubbles that can interfere with proper distribution of dampening
solution
Paste Ink - ANSWER-Ink with high viscosity; requires reduction in shear; litho and screen
Liquid Ink - ANSWER-low viscosity; must be rewet between impressions; flexo and gravure
Viscosity - ANSWER-resistance to flow; controlled by solvent
pH of Ink - ANSWER-if too low, ink will body up or become more viscous; if too high, poor water
resistance and unstable
How do we control pH? - ANSWER-amines are added to raise pH and evaporated to lower pH
Press-side Additives - ANSWER-reducers, extenders, retarders, surfactants
Extender - ANSWER-ink without pigment, allows for adjustment of color strength
