Difficulty: Easy & Basic
Why does a paste for reactive cotton printing often use alginate as a thickener?
A Strong reaction fixes dye
B It forms a metallic mordant
C It replaces the cellulose
D Low reaction with dye
Answer: D. Low reaction with dye. Suitable alginate thickeners interfere relatively little with reactive dyes and can be washed off after fixation.
Piezoelectric actuation in a printhead converts an electrical pulse into what mechanical change?
A Cure pigment on contact
B Rotate the fabric beam
C Shrink the nozzle opening permanently
D Deform an actuator
Answer: D. Deform an actuator. Deformation generates a pressure pulse in the ink chamber that drives out a droplet.
Why are reactive dyes and pigment particles fixed differently?
A Dyes need no fixation ever
B Different attachment mechanisms
C Pigments dissolve cellulose
D They use identical bonding
Answer: B. Different attachment mechanisms. Reactive dyes can bond with fibre groups. Pigments are held mainly by a cured binder.
In roller printing, what does a doctor blade remove?
A Excess paste between cells
B Yarn protrusions only
C Fabric from the blanket
D Dye from printed fibres
Answer: A. Excess paste between cells. A doctor blade wipes surplus paste from the unengraved roller surface while paste remains in the cells.
If red and blue are both to be printed through separate conventional stencils, what is prepared for the design?
A A common tensile chart
B A single tangled yarn
C One bath blend
D Colour separations
Answer: D. Colour separations. Separations define which areas each distinct colour screen prints.
Across an otherwise uniform inkjet field, what defect can a blocked nozzle leave?
A A stronger dye bond
B A longer repeat scale
C Repeated missing print lines
D Higher fabric warp count
Answer: C. Repeated missing print lines. A nozzle that fails to fire leaves unprinted rows or bands wherever it should deposit ink.
Dye printing often uses moist steam after drying. What does steam help provide?
A Permanent resin on fabric
B Dry warp size
C Cold air pressure only
D Heat and moisture
Answer: D. Heat and moisture. Steam supplies heat and moisture that help dye move and react under the selected fixation conditions.
Wax patterning in batik uses which principle?
A Uniform pigment coating
B Resist printing or dyeing
C Dry fibre drawing
D Mass colour blending
Answer: B. Resist printing or dyeing. Wax blocks dye uptake in the areas it covers.
What does a print strike-off provide before full production?
A A small trial print
B An unfixed dye bath
C A textile strength report
D A spinning yield chart
Answer: A. A small trial print. A strike-off allows the design, colour and print quality to be checked on a sample.
What undesirable effect can excess pigment binder have on fabric handle?
A It eliminates all stiffness
B It reduces all fibre lengths
C It can stiffen fabric
D It removes all colour
Answer: C. It can stiffen fabric. A heavier polymer film can increase stiffness and change the feel of the printed surface.
Where does fresh paste enter a typical rotary screen during production?
A Through the fabric selvage
B Inside the yarn package
C Below the dryer belt
D Inside the cylinder
Answer: D. Inside the cylinder. Paste flows into the rotating screen, and the internal squeegee forces it through the open pattern areas.
Choose the machine commonly better suited to long continuous runs of one repeating design.
A Rotary screen machine
B Sample winding machine
C Hand block table
D Hank dyeing machine
Answer: A. Rotary screen machine. Continuous fabric movement under rotating colour screens supports high output on longer runs.
Why is the transfer paper image often mirrored before heat transfer?
A Heating doubles image width
B Transfer reverses the image
C Paper makes colour disappear
D Fibre turns its shade
Answer: B. Transfer reverses the image. The printed paper is placed face down, so directional designs such as lettering must be mirrored beforehand.
During print paste mixing, bubbles persist. Which auxiliary is used to reduce unwanted foam?
A Dye mordant
B Optical brightener
C Defoamer
D Warp sizing oil
Answer: C. Defoamer. A defoamer destabilises bubbles formed during mixing or printing.
Coloured discharge requires the added colourant to tolerate which action?
A The discharge chemistry
B Fabric count adjustment
C Mechanical carding
D The looming of yarn
Answer: A. The discharge chemistry. The colourant used for the new motif should remain stable while the ground dye is discharged.
How does a drop-on-demand printer deliver ink?
A All nozzles spray constantly
B Paste flooded through screens
C Drops ejected when commanded
D Uniform roll immersion
Answer: C. Drops ejected when commanded. Individual nozzles eject drops only when the pattern data calls for them.
Wet paste touches a guide and leaves a blurred streak. Which defect class fits?
A Fabric pilling
B Fibre melting at spin
C Smearing
D Chemical shade metamerism
Answer: C. Smearing. Contact with wet printed areas can displace paste and blur or streak the design.
Before fabric enters the print station, which condition can distort the design?
A Creased fabric
B Uniform flat feeding
C Stable fabric width
D Even blanket speed
Answer: A. Creased fabric. Creases alter contact and alignment, leaving gaps, overlaps or marks when the fabric is flattened.
Why is fabric lightly held to the blanket during multicolour screen printing?
A Fix pigment thermally
B Increase cotton fibre fineness
C Remove all natural tint
D Prevent fabric shifting
Answer: D. Prevent fabric shifting. Holding fabric in place helps preserve alignment between successive colour applications.
In a reactive inkjet process, which preparation helps limit spreading on cotton?
A Longer dye bath depth
B Suitable fabric pretreatment
C Additional warp size only
D A hotter storage chamber
Answer: B. Suitable fabric pretreatment. Pretreatment can control droplet spread and supply chemistry needed during fixation.
In white discharge, what mainly happens to the background dye in printed areas?
A It is locally decolourised
B Starch covers the dye
C It becomes extra dark
D It is redistributed uniformly
Answer: A. It is locally decolourised. The selected chemical action destroys or removes colour in the printed areas.
Flatbed printing can apply several squeegee strokes over one impression. Which product can benefit?
A Dry pigment powder
B Pile towels
C Lightweight yarn packages
D Bare polyester chips
Answer: B. Pile towels. Multiple passes can deposit enough paste to penetrate the surface of a thick pile fabric.
Weak colour coincides with blocked screen openings. What directly explains the fault?
A Faster print curing
B Higher dye bath exhaustion
C Insufficient paste transfer
D Greater fabric width
Answer: C. Insufficient paste transfer. Paste cannot reach the cloth in the intended amount where openings have become blocked.
Which advantage makes inkjet useful for short design trials?
A It never needs pretreatment
B No separate pattern screens
C Paste thickness is irrelevant
D Every print needs cylinders
Answer: B. No separate pattern screens. The design can be changed digitally without preparing a new physical screen for every colour.
Why should printheads be maintained between inkjet jobs?
A Preserve consistent droplet delivery
B Automatically dry all paste
C Increase the number of fibres
D Change the polymer identity
Answer: A. Preserve consistent droplet delivery. Cleaning and maintenance help prevent blocked nozzles and unstable drop formation.