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Author Topic: Why do clothes shrink?  (Read 8821 times)

paul.fr

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Why do clothes shrink?
« on: 27/07/2007 22:04:17 »
every so often, i always manage to shrink some clothes whilst washing them. Now, i know that the water was probably too hot, but why should this make clothes shrink?


 

Offline Chemistry4me

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Why do clothes shrink?
« Reply #1 on: 27/02/2009 11:14:21 »
 

Offline dentstudent

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Why do clothes shrink?
« Reply #2 on: 27/02/2009 11:26:28 »
Doesn't this happen more frequently on natural fibres, and especially with wool?
 

Offline Chemistry4me

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Why do clothes shrink?
« Reply #3 on: 27/02/2009 11:28:57 »
And what does it have to do with physics/astronomy?
 

Offline Don_1

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Why do clothes shrink?
« Reply #4 on: 27/02/2009 11:48:48 »
Natural fibres do not exactly shrink, they return to their natural size.

During the manufacturing processes, the fibre gets stretched by the tension created by the machines.

Wool and cotton are stretched during the spinning process which turns them into useable yarn. This is further stretched during the knitting or weaving process. When washed, the tension is released and the fibres return to their natural state.

These days most natural fibres are 'pre-shrunk'. Wool is washed after spinning, so the tension is released. Cotton is washed after spinning and again after weaving (I think).

Pre-shrunk woven fabrics can then go to the CMT (Cut, make & trim) stage without fear of further 'shrinkage'. I think in the case of wool, low tension knitting machines are used.
 

Offline lightarrow

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Why do clothes shrink?
« Reply #5 on: 27/02/2009 11:51:31 »
Natural fibres do not exactly shrink, they return to their natural size.

During the manufacturing processes, the fibre gets stretched by the tension created by the machines.

Wool and cotton are stretched during the spinning process which turns them into useable yarn. This is further stretched during the knitting or weaving process. When washed, the tension is released and the fibres return to their natural state.

These days most natural fibres are 'pre-shrunk'. Wool is washed after spinning, so the tension is released. Cotton is washed after spinning and again after weaving (I think).

Pre-shrunk woven fabrics can then go to the CMT (Cut, make & trim) stage without fear of further 'shrinkage'. I think in the case of wool, low tension knitting machines are used.
Good post.
 

Offline yor_on

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Why do clothes shrink?
« Reply #6 on: 27/02/2009 16:52:05 »
I suceeded in washing a knitted sweater once, sent by a girl that I shared a mutual, ah, interest, in.
It was washed at 90 degrees celcius and after washing it fitted my cat perfectly :)
Not that my cat became any happier though?

---

And I never dared to tell her either ::))
« Last Edit: 27/02/2009 16:54:26 by yor_on »
 

Offline Chemistry4me

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Why do clothes shrink?
« Reply #7 on: 27/02/2009 23:09:25 »
You washed it with your hands Mr. yor_on or in the washing machine? :)
 

Offline yor_on

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Why do clothes shrink?
« Reply #8 on: 28/02/2009 17:52:55 »
Huh?
What's a 'washing machine'?

Hmm, ok, the coin fell finally down :)
No Mr Chem, she was in France at the time.
 

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Why do clothes shrink?
« Reply #8 on: 28/02/2009 17:52:55 »

 

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