black kites

[nayy]

Hello all,

Today a seller told me that the black kite fabric is the strongest one...

the explanation is, that after the weaving the fabric has a yellowish colour that has to be bleached before adding the definitive colour.
The black fabric does not need that bleaching step, because black covers everyting...

Can anybody confirm this explanation... it seems logic to me but never heard it before...

Thanks,

Nayy

[Barryg101]

I heard that black is mostly used as it's the cheapest color to manufacture the kites in , plus black kites wear the fastest as canopy heats up faster being black and the UV rays cause more damage and breaks down the materials at a faster rate than other colors .

[jumptheshark]

No clue on that one.

As the owner of both all white and all black kites. The blacks ones deal with goose shit, mud and mildew a hell of a lot better. They look great for waaayyyyyyy longer.

[Regis-de-giens]

My ex-Speed2 dlx was black and kept a good cloth quality for long time.

If I had had the opportunity for my very light marginal wind kite, i would have chosen black despite the poor visibility but for optimizing the (polemic) hot ballon effect .

[tautologies]

WTF.
no it's bullshit. Ask how the kite had been protected against UV light. That's it. Everything else is dumb.

[NorCalNomad]

Working with high strength technical textiles in my job, of both poly and nylon content.

100% bullshit

[SaltWaterDog]

I’m no expert but all 3 of mine are looking just fine after a year of heavy use.

[rynhardt]

don't know about longevity, but black kites just look ugly. And I own one.

[nixmatters]

90% BS I would say, especially in the part of bleaching, which with off-white raw polyester (not yellowish) is done with optical brighteners that do not harm the yarn mechanical properties like chlorine bleaching of cotton.

A statement that a black fabric would resist UV exposure better than exactly the same white or light color fabric is though partially true.

UV rays break the bonds in polymer chains, which is the sole reason for mechanical properties deterioration. There are different ways to combat this, some of which:
- Organic UV inhibitors that are surface coated (fiber or fabric coating). With polyester ripstop used for the kite canopy these inhibitors are mostly added in the final PU fabric coating that makes it stiff (crispy) and also air impermeable. UV radiation effectively destroys these inhibitors (thus protecting the coated fabric) and their effect deteriorates with time/exposure.
- Inorganic UV blockers/inhibitors, that are added to the yarn at a very early production stage or later on during dyeing. The most common of these is TiO2, which btw is also used as optical brightener for achieveing snow white and light bright colors.
- Carbon black that is added at fiber extrusion stage (mass/dope/solution dyed). Rare to non-existent in high-tenacity poyester fiber used for kite canopy ripstop and high-performance textiles. Mostly used for achieveing pitch black colour that does not fade with prolonged UV exposure.
- Black and very dark colours of post dyed fabric (after weaving) do add to a certain extent a UV protection by creating a filter/shade on the surface of the fiber, blocking the UV radiation to penetrate deeper. The most common dyeing process used for polyester yarn and fabrics is disperse dyeing, which means tiny dyestuff particles get stuck between the polymer molecules, not causing (almost) any change to the properties at molecular level.

To Barryg101's comment that black coulour heats up faster/more - this in effect serves as a UV filter. When part of the UV radiation energy is converted into heat by 'dark' colour substrates, there is less energy left to destroy the polymer bonds.
The maximum temperature a black kite can heat up to when exposed to direct sunlight is far below the levels needed for fiber/coating properties deterioration. Considering of course that we mosty leave our kites out in windy/cool environment (pun intended)

Again, the claim that a black fabric has a higher UV resistance (mechanical properties) is partly true, but very generalized.
The coating quality is much more important than he colour of the fabric. As is the quality of the polyester fiber.

If someone is very keen on doing a comparative testing, a UV testing/curing lamp costs less than $100 and it's not a rocket science to conduct such DIY test.

[CaptainCore]

From memories of a previous life in the Print game Red is the worse colour for UV degradation, I wouldn't imagine the fabric is affected that badly unless used commercially for long periods left inflated on the beach to flap in the wind. Wind flapping does more damage in a couple of hours than weeks of normal UV.