Pulp and Paper Multiple Choice Questions on “Ink and Ink Applications”.
1. Ink consists of pigments or dyes, a vehicle (binder) to attach the pigment to the paper
a) True
b) False
Answer: a
Clarification: Ink consists of pigments or dyes, a vehicle (binder) to attach the pigment to the paper, and include solvents for faster drying and ink additives.
2. Ink consists of pigments such as __________ to supply color and opacity and a vehicle to carry the pigment and bind it to the paper.
a) Silicon oxide
b) Aluminium oxide
c) Titanium oxide
d) Zinc oxide
Answer: c
Clarification: The main utilize of TiO2 is as a white powder pigment because of its brightness and very high refractive index. Pigments should be insoluble in H2O and the ink formulation to prevent running.
3. Pigments which are _________ variant of organic dyes are called vat dyes.
a) Soluble
b) Insoluble
c) Acidic
d) Basic
Answer: b
Clarification: Vat dyes are essentially insoluble in H2O and incapable of dyeing fibres directly. However, reduction in alkaline liquor produces the H2O-soluble alkali metal salt of the dye, which, in this leuco form, has a similitude for the textile fibre.
4. Ink __________ are often heavy metal salts of (unsaturated fatty acid) soaps that promote oxidation and/or polymerization.
a) Ink paper sizing
b) Ink receptivity
c) Ink additives
d) Ink visibility
Answer: c
Clarification: Printing inks and overprint varnishes require good wetting of various substrates, excellent surface protection and defoaming, and good pigment stabilization. Paraffin-based wax emulsion for aq. coatings, printing inks as well as care products and polishes for improving H2O repellency and surface slip.
5. __________ of the ink vehicle leaves the solid ink with rosin esters and metal binders behind; this is utilized in magazine and catalogue grades utilizing letterpress or heat set web offset printing.
a) Sublimation
b) Liquation
c) Evaporation
d) Solidification
Answer: c
Clarification: To keep heating costs low, solvents with low boiling points, but not so low as to be unsafe, are utilized. The ink further sets by cooling to ambient temperatures.
6. __________ of a drying oil with multifunctional carboxylic acids and alcohols left on the paper surface after the vehicle is absorbed into the paper might promote polymerization.
a) Oxidation
b) Reduction
c) Radiation
d) Cracking
Answer: a
Clarification: Heavy metals (cobalt, manganese, lead) might promote oxidation with atmospheric O2. Since oxidation is the key to curing in these oils, those that are susceptible to chemical drying are often unsuitable for cooking, and are also highly susceptible to becoming rancid through autoxidation, the process by which fatty foods develop off-flavors.
7. __________ curing cautilizes monomers or pre-polymers in the vehicle to form polymers; it’s useful with acrylics.
a) Oxidation
b) Reduction
c) Radiation
d) Cracking
Answer: c
Clarification: They cure by air oxidation when O2 from the air reacts with unsaturated fatty acids in their drying oils. This method doesn’t have much utilize with paper, but is often utilized for metal and plastic substrates to avoid the utilization of large ovens.
8. Infrared hardening , precipitation of binders, gelation, and cooling of hot thermoplastic inks utilized in electrostatic printing.
a) True
b) False
Answer: b
Clarification: Infrared hardening , precipitation of binders, gelation, and cooling of hot thermoplastic inks utilized in electrostatic printing like photocopy and laser printers are other mechanisms utilized less often, but are decreasing in utilize.
9. __________ is the amount of paper that could be covered by ink to achieve a specified print density under operating conditions of a press.
a) Ink tack
b) Ink mileage
c) Ink additives
d) Ink visibility
Answer: b
Clarification: It is measured in English units of square inches per pound of ink. The concept could be developed as an input-transform-output equation. On the input side is ink of correct color and strength.
10. ____________ is a measure of the force or energy required to split a film of ink. In this regard the ink is like a contact adhesive.
a) Ink tack
b) Ink mileage
c) Ink additives
d) Ink visibility
Answer: a
Clarification: It’s an crucial aspect in the printing process that needs to be monitored for quality control. If a high force is required to split a film of ink, it might cautilize picking of the paper.
>