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Author Topic: Does bleach always...bleach?  (Read 9282 times)

Offline lightarrow

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Does bleach always...bleach?
« on: 12/06/2007 16:45:30 »
What would happen to a coloured shirt put in the bleach?
It looses its colour, of course.

What would happen to a white shirt?
Of course, it would whit...one moment! My shirt has become orange! How is possible?

In some parts only, and it doesn't go away! ???


 

Offline kdlynn

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Does bleach always...bleach?
« Reply #1 on: 12/06/2007 16:51:16 »
i don't know why, but it has happened to me also. my grandma once had blue spots!
 

Offline Karen W.

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Does bleach always...bleach?
« Reply #2 on: 12/06/2007 17:00:27 »
Sorry Alberto I do not know either. I imagine it may be the material it is made from, but I really haven't a clue!
« Last Edit: 13/06/2007 06:06:11 by Karen W. »
 

Offline kdlynn

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Does bleach always...bleach?
« Reply #3 on: 12/06/2007 17:05:17 »
i think it may have something to do with whether the bleach is applied directly to the material or is diluted in water first. if i put a little bleach in water then add white clothes i don't see funny spots, but if i throw it on there directly, i get spots
 

paul.fr

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Does bleach always...bleach?
« Reply #4 on: 12/06/2007 19:49:49 »
good question, sir.

not too sure of the answer though, did you bleach the shirt seperate from other items? I know that hair can turn orange after being "home bleached" and i think this happens because you do not use a Bleach Activator, Accelerator/Buffer. These are present in the bleaching kits you buy for your hair. maybe something similar was going on with your shirt.
 

Offline Bored chemist

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Does bleach always...bleach?
« Reply #5 on: 12/06/2007 20:10:32 »
"my grandma once had blue spots!"
Please do not try to bleach your Grandmother again.

Bleach is pretty aggressive stuff. Normally the easiest target for it is the dye you want to bleach but if there's nothing else it is capable of attacking the fibres from which cloth is made. The degradation products may be coloured.

Also, on a more general not, no bleach doesn't always bleach. For example it's no use at all on rust stains (you would be better with lemon juice).

 

Offline lightarrow

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Does bleach always...bleach?
« Reply #6 on: 12/06/2007 20:14:29 »
i think it may have something to do with whether the bleach is applied directly to the material or is diluted in water first. if i put a little bleach in water then add white clothes i don't see funny spots, but if i throw it on there directly, i get spots
Exactly.
 

Offline lightarrow

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Does bleach always...bleach?
« Reply #7 on: 12/06/2007 20:18:02 »
good question, sir.

not too sure of the answer though, did you bleach the shirt seperate from other items?
Yes, separately; it was only (just laundered) wet shirt and bleach.
 

Offline lightarrow

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Does bleach always...bleach?
« Reply #8 on: 12/06/2007 20:21:01 »
"my grandma once had blue spots!"
Please do not try to bleach your Grandmother again.
Fantastic! :D
Quote
Bleach is pretty aggressive stuff. Normally the easiest target for it is the dye you want to bleach but if there's nothing else it is capable of attacking the fibres from which cloth is made. The degradation products may be coloured.
Ok, but why in some parts only?
 

Offline lightarrow

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Does bleach always...bleach?
« Reply #9 on: 12/06/2007 20:22:13 »
Sorry Alberto I do not know either. I imagine it may be the material it is made from, but I rally haven't a clue!
Thank you the same!
 

Offline daveshorts

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Does bleach always...bleach?
« Reply #10 on: 12/06/2007 23:02:29 »
Bleach can change the colour of coloured shirts in unexpected ways - I had a blue T-shirt that a cleaner spilt bleach on when I was an undergraduate and it now has pink spots. This is because the blue dye was made up of a magenta and cyan (a turquoise colour) dyes, but the cyan one was obviously much more succeptible to bleach so it got destroyed first leaving spots a bright magenta... I still wear it sometimes...

This is how those pens that change colour when you write over them with a white pen work - the white pen is bleach and the pens contain two colourants.

Although this doesn't make a white shirt go orange... Had you spilt anything interesting on the shirt. Could you have left a red pen in the wash?
 

Offline kdlynn

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Does bleach always...bleach?
« Reply #11 on: 13/06/2007 04:45:13 »
ok, ok... i won't bleach grandma anymore. what about my sister?
 

Offline Bored chemist

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Does bleach always...bleach?
« Reply #12 on: 13/06/2007 18:59:29 »
I don't think daveshorts spent long enough playing with paint when he was in kindergarten.
I think it's much more plausible that a blue dye  was converted to a magenta one by reaction with the bleach.

"ok, ok... i won't bleach grandma anymore. what about my sister? "
Why? Did she do something particularly bad or do you just think she would look better with blue spots. Come to think of it perhaps you are just trying to do good science and testing that the experiment is repeatable.
« Last Edit: 13/06/2007 19:02:14 by Bored chemist »
 

Offline lightarrow

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Does bleach always...bleach?
« Reply #13 on: 14/06/2007 21:33:20 »
Although this doesn't make a white shirt go orange... Had you spilt anything interesting on the shirt. Could you have left a red pen in the wash?
No, of course. Another interesting thing is that the shirt looked quite good until it was almost completely dried. At the beginning, I thought someone had dripped a coloured liquid from above, while the shirt was out to dry, but the same happened another time after another washing with bleach. However I think I could explain this: bleach concentrates when it dries, so it becomes more active.
« Last Edit: 14/06/2007 21:37:23 by lightarrow »
 

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Does bleach always...bleach?
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