This blog is about finding a
suitable fabric for children´s wear. For most of the children´s wear, cotton is
the most used material. We talked about cotton during the men´s jeans blog, but
we didn’t go into depth about the production of cotton. This blog will give a
lot of information about the production of cotton with the emphasis on organic
cotton. Organic cotton is the chosen fabric in this blog.
Style
We’ve chosen to look for a fabric
which is suitable for a baby’s romper suit, whereas this will be the fabric the
closest to the skin. Garment for baby’s should be more comfortable, flexible,
soft and easy to wash than all other garments. The fabric is 100% organic
cotton.
Cotton and organic cotton
How normal cotton is made…
It all starts with the planting of
the cotton plant, which takes between 175 to 225 days to mature and grows
between 25 cm up to 2 meters. After the plant grows flowers, the fruits will
turn into capsules/bolls which eventually crack open to reveal the seed hairs.
Cotton is grown in tropical conditions, because it need plenty of water and
heat to ripen. Pesticides are used to combat the Cotton Weavel, and many other
harmful insects. It allows for a much larger yield from a crop, by reducing the
destruction from insects. The chemicals eliminate not only pests but also their
natural enemies. This interference with the ecosystem considerably reduces
biodiversity.
The harvesting is done either by
hand or by picking machines, this depends greatly of the development of the
country. You can understand that hand picking is better for the cotton and
people can separate the ripe from the unripe bolls and leave out any leaves,
whereas the machine will harvest the whole crop in once. If the harvested
cotton is wet, it needs to be dried by warm air before it can proceed to the
ginning process. In the ginning process the seeds are separated from the
fibres. The fibres which remain are called lint and has only 35% weight of
usable cotton compared to harvested cotton. After ginning there are several
cleaning processes to purify the cotton and form batts. Carding is the process
of combing the tangled fibres to equalize the fibres and produce slivers. These
slivers will be spun into yarn.
For everyone who needs this whole
process visualized can watch this video:
Quality of cotton
There is no generic system for the
measurement of cotton, but there are some commercially developed quality
measures. Mainly, the quality of cotton is designated by the origin of the
cotton, but it can also be measure by:
- · Staple length, the longer the length of the staple the better. The length lies normally between 20 and 40 mm. Sea island cotton can have 50 mm long staples;
- · Fineness, The longer the fibres, the finer it is and the softer the handle. The fineness is measured in weight per unit and can be between 1 and 4 dtex;
- · Impurities, Remaining Leafs, seeds, short or ‘dead’ fibres can severely lower the quality of cotton;
- · Strength, The relation between fineness and strength defines quality. A fine cotton with a high strength gives quality;
- · Colour and lustre, The color of cotton can vary from white, creamy to light yellow or brown. High quality cotoons have a silky lustre.
What makes organic cotton, organic?
According to WWF research, it takes
an average of 8,500 litres of water to grow one kilo of cotton lint, which is
enough to make one pair of jeans.
Organic cotton is cotton that, is
grown without chemical pesticides or fertilisers. It relies on the use of
natural enemies, such as ladybirds to suppress harmful insects. It does not use
genetically modified organisms, but seeks to build a biologically diverse
agricultural system, replenishing and maintaining the soil’s fertility. Organic
cultivation also reduces the potential negative impact of cotton production on
local water quality and biodiversity. Most organic cotton is grown in Turkey,
India and China.
Want to know more? Check www.organiccotton.org or watch organic cotton made in
turkey https://www.youtube.com/watch?v=RTCWfZ2sx0g
Use of chemicals in the production process
Besides the cotton being organic it
is also important, especially for children´s clothing, that no harmful
chemicals are used in the production of the fabric. A search on the internet
about harmful chemicals in clothing ends up in a lot of difficult words, such
as persistence, bioaccumulation, toxicity, carcinogenicity, mutagenicity and
toxicity to reproduction, endocrine disruption and equivalent properties. We
will not go into depth about all the different chemicals, but it is useful to
have a look at the chemical restriction list of H&M. Our fabric is organic
cotton sourced by H&M, so it will meet the requirements stated by the
Chemical Restrictions list of H&M.
This link shows a video about
sustainability in H&M: http://about.hm.com/content/dam/hm/about/videos/CSR/HM_Enviroment.mp4.form.html/content/hm/NewsroomSection/en/NewsRoom/assetviewer.html
Fabric
construction
The fabric is weft knitted in a 1X1
rib fabric. Rib fabric is made on a two needle bed with the needles in a
staggered formation, which means that the needles are not placed with the same
height, but different one by one. The loops are drawn in opposite directions so
that face and back loops alternate in each course. Both sides of the fabric
show only the face loops. When you stretch the fabric from side to side the
back loops are exposed. Rib fabrics are very extensible in the width. The yarn has a Z-twist. The chemical restriction list of H&M states which dyes are approved for the clothing. The yarn is probably colored with a disperse dye, which is approved in a 1 mg/l extract.
The video shows the production of
rib fabric. You can see the difference in face and back loops by watching the
meshing points. If the legs of the loop are behind the head of the loop, it is
a back loop (the right wale in the video) and if the legs of the loop are over
the head of the loop it is a face loop (the left wale in the video)
While the book says purl fabric is
used for romper suits. The functional difference between purl and rib fabric is
that rib fabric has a wide extensibility in the width and the purl fabric has
extensibility in the length. A romper suit is closet at the bottom and should
have some extensibility in the length if it is pulled over the head to the
bottom to close it. Baby’s grow a lot in the length and are very flexible and
movable. Therefore we recommend to use purl fabric in the body, which is very
extensible in the length and rib fabric for the sleeve.
There are 10 face loop wales shown
in the picture, which means there are 20 actual wales. There are between 17 and
18 courses in one cm.
Stitch
The stitches in the romper suit
should be extensible, but firm. After examining the Clothing Technology book,
we think the stitch used in the neck is a type 406 Flat seam stitch. (page 176)The hem in the sleeve is probably
stitched while the fabric is stretched, like the other stitches. You can see
that the stitch yarn is loose, but when you stretch out the sleeve it gives
great extensibility, without breaking the yarn. When you un stretch it, the
yarn forms loose loops.
Testing
Washing for shrinkage test, before
we washed the fabric we measure it and the measurements are 15.2 cm by 13,3 cm.
After the washing we measured the fabric when it was wet and the measurements
were 14,5 by 14,3. After drying the fabric in the tumble dryer it had the following
measurements 14,2 by 13,5.
Washing for color fastness test, we
washed the fabric with program C1M, which means we washed it on 60 degrees for
45 minutes with 50 steel balls, test fabric and a detergent. The results are
shown in the picture. We grade the changes in the cotton test fabric a 3, the
polyamide a 4/5 and the viscose a ¾. The rest of the test fabric is fairly
white, but the water colored blue.
Rubbing for color fastness test, we
used a wet cotton in the rubbing machines to test the color fastness to rubbing
and the result on the cotton fabric is graded with a 4. You can also see that
it left some pills of the fabric.
Martindale for abrasion test, we
performed 4 tests on the martindale machine. The first one (upper left) was with a rotation
of 500 times and got a grade 4/5. The second test (upper right) is a rotation of 1000 times
and has a grade 4/5. The third test (bottom right) has a rotation of 2000 times and got the
grade ¾ and the last test (bottom left) had a rotation of 5000 times and got the grade 2/3.
The fabric is not really suitable for garments which have to be durable,
whereas the fabric pills, but for children’s wear it is not that bad.
We performed the pilling test with
9300 rotations. The fabric is only a little bit hairier, but there are not
pills. The test is not performed totalle, whereas it should be performed 5
times for 18000 rotations, but there was no time to perform the whole test.
The bursting test showed that the
fabric bursts at 185.3 Kilo Pascal. It took 18.5 seconds for the fabric to
burst and 36.9 mm of extension before the fabric bursted.
We also performed an extension and
recovery test, whereby the machine extends the fabric 5 times with about 100.1
kilo pascal of pressure for 5 seconds. The result shows that the fabric is
formed by the pressure. The recovery is not 100 percent.
The weight of the fabric is 183
grams per square meter or 5.40 ounce per square yard.
Properties
Did you know that the head of a baby
is relatively much bigger than the body? That’s why the neck of the baby
bodysuit needs to be stretchy to get the garment over the head of the baby.
Therefore most baby bodysuits are made of a knitted fabric. The freedom of movement is very
important for a baby, since they crawl around all the time. Furthermore the
children´s wear should allow to put on diaper. Therefore a stretchy jersey is
very useful.
The skin of a baby is very
sensitive. So a very soft fibre should be used for the clothing. Mostly cotton
is used for that, since it has the best properties. Also cotton is easy to wash
and can be washed on high degrees to make the clothes hygienic.
Care instructions
The cotton fabric can be washed on a
high temperature, to clean it hygienic. You should use no chlorine bleach,
because of the bright color. Tumble dry and iron on medium level. That´s
important, since cotton wrinkles very easily.
References
Clothing Technology from fibre to
fashion fifth edition 2008
Fabric for fashion, The swatch book
first edition 2010
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