Finishing 1:
colour chemistry
pre-treatment
pre-treatment
Overview process steps:
1. Batch formation (batchvorming)
2. Singeing/shearing (zengen)
3. Desizing (ontsterken)
4. Scouring (afkoken)
5. Acidification (afzuren)
6. Carbonization (carboniseren)
7. Chlorination (chloreren)
8. Bleaching + OB (bleken en optisch wit)
9. Mercerization (mercerizeren)
10. Rinsing (spoelen)
11. Drying (drogen)
process can be either continuous or discontinuous
process can be either open width or tube form
why do we do finishing?
- removal impurities like salts, pesticides, starch, dust, seed coat fragments.
- change properties of the fabric
- prepare the fabric for the next process
1.batch formation:
the substrate has standard lengths: 100 - 200 - 500 - 1000 mts. A batch must be formed to
create a longer fabric. This means after weaving or knitting the fabric (the substrate) are
attached to create a bigger one. (for a continuous process you need >10.000mts)
1
,sowing of the pieces is very important, think of:
- seam breakage
- formation of batch
- good sides sown together
- first inspection in finishing process
2.singeing or shearing
singeing:
continues or discontinues
projecting fiber ends are burned away using one or
more banks of gas flames or another heat source.
gains: improved fabric properties, smoother
surface, weave/knit is revealed more clearly,
development of hairiness and pilling is reduced.
(often done on cotton)
there is three
methods:
- perpendicular on the fabric (straight on fabric)
- perpendicular on the fabric with a cooler roller
- tangential singeing (with an angle)
2
, (left is a circular singeing machine)
shearing: shaving of the protruding fibers with a rolling knife (think of a lawnmower)
flattens out material as the same time it shears. can be done on any material but never in
rope form.
If you pull knitted material on a stanter frame (frame with pins on the side) you get the holes on the
side from the stanter frame (you can often see these in the selfedge of a bought material), shearing
flattens fabric so you don’t need a stanter frame.
process parameters:
- fabric speed
- flame intensity
- flame distance
- flame position
3.desizing
the aim of desizing is to remove size and other substances applied as weaving aids. Done
with enzymes, oxidizing agents or washing, depending on the type of size. Size needs to be
removed because the fabric needs to be hydrophilic to be able to apply the next finishing
step.
Apply size(starch, greasy oily) in warp yarns to make the weaving process easier → sizing
Removing size and other substances from material → Desizing
3
colour chemistry
pre-treatment
pre-treatment
Overview process steps:
1. Batch formation (batchvorming)
2. Singeing/shearing (zengen)
3. Desizing (ontsterken)
4. Scouring (afkoken)
5. Acidification (afzuren)
6. Carbonization (carboniseren)
7. Chlorination (chloreren)
8. Bleaching + OB (bleken en optisch wit)
9. Mercerization (mercerizeren)
10. Rinsing (spoelen)
11. Drying (drogen)
process can be either continuous or discontinuous
process can be either open width or tube form
why do we do finishing?
- removal impurities like salts, pesticides, starch, dust, seed coat fragments.
- change properties of the fabric
- prepare the fabric for the next process
1.batch formation:
the substrate has standard lengths: 100 - 200 - 500 - 1000 mts. A batch must be formed to
create a longer fabric. This means after weaving or knitting the fabric (the substrate) are
attached to create a bigger one. (for a continuous process you need >10.000mts)
1
,sowing of the pieces is very important, think of:
- seam breakage
- formation of batch
- good sides sown together
- first inspection in finishing process
2.singeing or shearing
singeing:
continues or discontinues
projecting fiber ends are burned away using one or
more banks of gas flames or another heat source.
gains: improved fabric properties, smoother
surface, weave/knit is revealed more clearly,
development of hairiness and pilling is reduced.
(often done on cotton)
there is three
methods:
- perpendicular on the fabric (straight on fabric)
- perpendicular on the fabric with a cooler roller
- tangential singeing (with an angle)
2
, (left is a circular singeing machine)
shearing: shaving of the protruding fibers with a rolling knife (think of a lawnmower)
flattens out material as the same time it shears. can be done on any material but never in
rope form.
If you pull knitted material on a stanter frame (frame with pins on the side) you get the holes on the
side from the stanter frame (you can often see these in the selfedge of a bought material), shearing
flattens fabric so you don’t need a stanter frame.
process parameters:
- fabric speed
- flame intensity
- flame distance
- flame position
3.desizing
the aim of desizing is to remove size and other substances applied as weaving aids. Done
with enzymes, oxidizing agents or washing, depending on the type of size. Size needs to be
removed because the fabric needs to be hydrophilic to be able to apply the next finishing
step.
Apply size(starch, greasy oily) in warp yarns to make the weaving process easier → sizing
Removing size and other substances from material → Desizing
3