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Author Topic: UV damage to fabric  (Read 4343 times)

Offline sandykoeck

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UV damage to fabric
« on: 30/08/2005 17:36:53 »
Hi -
totally new here - and this is my story:
Motorcycle covers seem to suffer from UV like any other fabric, and in my case ripped on the top - just like previous ones - kind of "frazzled".
I HEARD once, BLACK was the color to use as it responds(?) least to UV, I would think maybe white would be good - what's the scientific take on this?
I am planning to buy some fabric ("awning material") that is supposed to hold up pretty good - now to choose the color
Thanks

Sandy in Montana


 

Offline daveshorts

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Re: UV damage to fabric
« Reply #1 on: 30/08/2005 18:37:19 »
I think the reason that black would be good is that the UV is quite a high enery radiation that will damage the structure of the plastic, so if you add a dye that will absorb all colours of light (black) before it gets to much of the plastic the UV can do less damage. You can get some plastics with essentially a sunscreen in them to make them more UV resistant (UPVC windows for example), but failing this a dark colour will probably absorb UV as well - especially if it is redish rather than blue as a red colour will absorb green and blue already so will probably also absorb UV which is close to blue in wavelength.
 

Offline sandykoeck

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Re: UV damage to fabric
« Reply #2 on: 31/08/2005 03:54:12 »
Thanks, davehorts -
that raises another "sientific" question from the absolut ignoramus here:
Shouldn't I try to find something that absorbs least
UV light, as in rather reflect it, since the damage is created by the absorption?????
Or what actually does the damage????
Thanks


Sandy in Montana
 

Offline daveshorts

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Re: UV damage to fabric
« Reply #3 on: 31/08/2005 13:47:42 »
If you could reflect the UV off the surface that would be great, but most white fabrics work by refracting the light several times, which means the UV gets into the fibres. The idea is that the dark dye molecules absorb the UV not the polymers in the plastic, so protecting them.
 

Offline sandykoeck

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Re: UV damage to fabric
« Reply #4 on: 01/09/2005 03:29:14 »
Thanks -
what about fabric without plastic?
Would red or orange actually be best, according to your first explanation?

Sandy in Montana
 

Offline daveshorts

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Re: UV damage to fabric
« Reply #5 on: 01/09/2005 10:57:44 »
I think natural fibres (all the rest are plastic) are less suceptable to UV damage, the problem there comes from water and bacteria. Black would be best as this absorbs everything, but if you want a colour red is probably better than blue (althogh this is based on extrapolating UV absorption from blue absorption  which is a bit dodgy)
 

Offline sandykoeck

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Re: UV damage to fabric
« Reply #6 on: 01/09/2005 15:09:47 »
Thanks - black it is, then!

Sandy in Montana
 

The Naked Scientists Forum

Re: UV damage to fabric
« Reply #6 on: 01/09/2005 15:09:47 »

 

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