Re: Why all computer casing & cables are black?

On Sat, 11 Jul 2026 19:18:48 +0800, "Mr. Man-wai Chang"
<[email protected]> wrote:

>On 7/11/2026 11:32 AM, Jeff Liebermann wrote:
>> 
>> You might be looking at the casing and cables in the dark.  Without
>> light, what's left is dark.  Try turning on a light.
>> ....
>> If you're wearing smart glasses or auto-darkening welding goggles,
>> check if it's turned on, properly adjusted and if the battery is fully
>> charged.
>
>Why isn't the default color WHITE? Or red? Why black? :)

Because the outer sheath of cables needs to be UV resistant.  That's
done by adding carbon black to the mix during manufacture.  Carbon
black has and important attribute.  It is cheap.  If you want a white
outer sheath, the manufacturer would likely add titanium dioxide,
which costs more.

<https://www.facebook.com/Elec.Eng.World/posts/cable-outer-sheaths-are-often-black-because-carbon-black-is-added-for-excellent-/1365758712263483/>
"Cable outer sheaths are often black because carbon black is added for
excellent, cost-effective UV resistance, preventing sun damage, and it
also offers good durability against mechanical wear, making black a
practical default for outdoor or heavy-duty cables, though other
colors exist for specific applications like data or color-coding."

"The Roles of Carbon Black in Wire & Cable Conductor, Insulation and
Jacketing Applications"
<https://www.birlacarbon.com/the-roles-of-carbon-black-in-wire-cable-conductor-insulation-and-jacketing-applications/>

-- 
Jeff Liebermann                 [email protected]
PO Box 272      http://www.LearnByDestroying.com
Ben Lomond CA 95005-0272   AE6KS    831-336-2558