Padding increases a fabric lot’s mass from 40 kg dry to 66 kg wet. What is the wet pickup?
A 65%
B 39.4%
C 60.6%
D 165%
Answer: A. 65%. The retained liquor is 26 kg. Divide by the 40 kg dry mass.
After heat setting, which practice helps a thermoplastic fabric retain its target width during cooling?
A Release width at peak temperature
B Wet it with dye immediately
C Keep width constrained initially
D Apply more warp twist
Answer: C. Keep width constrained initially. Cooling first under control reduces motion of the polymer chains before the fabric is released.
In a heated zone 18 m long, cloth runs at 12 m/min. How long does it remain in the zone?
A 30 s
B 60 s
C 90 s
D 216 s
Answer: C. 90 s. Residence is 18/12 minutes, or 90 seconds.
Why compare fabric hand using the same conditioning history?
A Hand depends only on colour
B Conditioning changes fibre identity
C Humidity always erases a finish
D Moisture can affect handling
Answer: D. Moisture can affect handling. Moisture and conditioning can affect how the fabric bends or feels, so matched conditions are important.
Compaction shortens 100 m of fabric to 94 m. Find its length reduction relative to feed length.
A 6%
B 4%
C 94%
D 6.38%
Answer: A. 6%. The length is reduced by 6 m per 100 m of incoming fabric.
Which combination best demonstrates water protection with acceptable moisture comfort?
A Tear strength and yarn twist
B Pill rating and seam length
C Light fastness and mass
D Water resistance and vapour transmission
Answer: D. Water resistance and vapour transmission. Liquid water resistance and vapour transfer measure two different functions important to rainwear comfort.
Finished dry mass increases from 50 kg to 52 kg. If the fabric loses no original material, what is dry add-on?
A 2%
B 104%
C 3.85%
D 4%
Answer: D. 4%. The 2 kg dry gain is 4% of the original 50 kg.
Choose the best comparison to determine if a softener slows towel wetting.
A Matched drop absorption times
B Finished package dimensions
C Fibre strength in tension
D Different fabric yarn counts
Answer: A. Matched drop absorption times. Drop absorption time can show slower wetting when treated and untreated specimens are otherwise comparable.
Length marks are 500 mm apart before washing and 495 mm apart afterwards. What is percentage shrinkage?
A 0.1%
B 99%
C 1%
D 5%
Answer: C. 1%. The 5 mm drop is 1% of the original 500 mm.
For continuous foam finishing at equal chemical add-on, why might drying energy fall?
A The yarn count decreases
B The fibre melt point rises
C Less water is carried
D More fabric mass evaporates
Answer: C. Less water is carried. Lower liquid pickup means the dryer may have less water to evaporate.
In a cured finish, the textile looks satisfactory while dry but loses its intended function after the first wash. Which issue should be investigated?
A Warp angle in weaving
B Poor finish durability
C Higher fibre length
D Increased staple fineness
Answer: B. Poor finish durability. A lost effect after washing points to weak attachment, insufficient cure, or another issue affecting durability.
Pickup is 70% and the liquor contains 5% nonvolatile finish by mass. What dry add-on is expected if no finish is lost?
A 3.5%
B 14.0%
C 7.0%
D 5.0%
Answer: A. 3.5%. Each dry kilogram retains 0.70 kg of liquor, containing 0.035 kg of solids.
Absorbency varies across the treated fabric although bath chemistry is consistent. Which application factor should be checked?
A Variation in liquor pickup
B Camera exposure settings
C Fabric roll label colour
D Length of dry yardage only
Answer: A. Variation in liquor pickup. Uneven pickup can leave different finish quantities across the fabric even with identical bath concentration.
Suppose 35 g of surface fibre is removed from 700 g dry fabric during biopolishing. Find percentage mass loss.
A 4.75%
B 95%
C 5%
D 0.5%
Answer: C. 5%. Divide removed mass by original mass: 35/700 × 100%.
After adding a stiffening finish, bending length rises under the same cantilever method. What change is supported?
A Increased bending stiffness
B Increased yarn count
C Higher water penetration
D Loss of textile mass
Answer: A. Increased bending stiffness. For otherwise comparable specimens, a larger bending length is consistent with greater resistance to bending.
A nominally fixed flame-retardant finish gives good results initially but deteriorates after washes. What should be measured after matched washing cycles?
A Only lamp colour
B Only the yarn count
C Only the presser pressure
D Flame response again
Answer: D. Flame response again. Repeating the specified flame test after laundering measures retention of the intended performance.
Width stays stable after stentering, but the cloth changes length after cooling. Which direction still needs stabilisation?
A Thickness direction
B Lengthwise direction
C True-bias direction
D Widthwise direction
Answer: B. Lengthwise direction. Width control does not by itself stabilise length. Separate control of lengthwise relaxation may be needed.
Apply finish at 2% dry add-on to 250 kg of dry fabric. How much dry finish must remain?
A 12.5 kg
B 5 kg
C 2 kg
D 0.5 kg
Answer: B. 5 kg. The required dry gain is 0.02 × 250 kg.
Under the same angle method, the crease recovery opening increases after treatment. What does it indicate?
A Less recovery from creasing
B Higher fabric shrinkage
C Better recovery from creasing
D Poorer colourfastness only
Answer: C. Better recovery from creasing. A larger opening angle means the folded specimen has returned farther toward its original flat condition.
The finish bath has 4 kg of active material at 20% by mass. What total formulation mass is present?
A 0.8 kg
B 20 kg
C 5 kg
D 24 kg
Answer: B. 20 kg. A 20% mass fraction means active mass equals 0.20 times the total mass.
Fabric exits a dryer wet on both edges but dry at the centre. What measurement can pinpoint the problem?
A Whole roll dye exhaustion
B Yarn twist across a cone
C Average package diameter
D Moisture profile across width
Answer: D. Moisture profile across width. A cross-width moisture profile quantifies where drying is insufficient and helps diagnose uneven conditions.
Switching to a hotter calender roll changes both gloss and hand. What experimental change isolates the effect of temperature more clearly?
A Use different artwork patterns
B Change fibre type simultaneously
C Change warp density too
D Keep nip pressure constant
Answer: D. Keep nip pressure constant. Holding pressure and other settings fixed makes a comparison of different temperatures easier to interpret.
Why might antistatic test results be poor at low humidity for a moisture-dependent finish?
A Less surface moisture conducts
B Reflectance always becomes zero
C More warp size is added
D More cotton yarn twist develops
Answer: A. Less surface moisture conducts. Some finishes rely partly on conductive surface moisture. Lower moisture availability can reduce charge dissipation.
Average pickup meets its target, yet finished colour varies across the fabric. Which application problem can still be present?
A Identical fabric in all lots
B Uneven pickup across width
C No finish was applied
D Equal finish in every area
Answer: B. Uneven pickup across width. An overall average can hide differences across the width. Uneven finish deposits can change appearance locally.
Which specimen comparison helps distinguish persistent surface texture from an effect that disappears on washing?
A Two unrelated production lots
B Before and after care
C Different fibre counts only
D Two rolls before finishing
Answer: B. Before and after care. Comparing a matched treatment before and after laundering evaluates retention of its texture.