Does sunlight cause bricks to decay?

I am aware that older rubber bands are notorious for decaying, and that parts will yellow in certain conditions, however will sunlight eventually cause bricks to decay/become fragile?
If so, does it apply to all materials? (ABS, Polyethene, SBS, Polycarbonate etc.)


I’m not sure, i know it will bleach them out and cause the colors to fade, but i don’t think it will make them brittle.


Okay, from what i can find, not to any degree you’ll probably have to worry about. ABS Takes a while(by which I mean a year or so), but it will slightly deform. I’m sure most materials will. If only because heat makes things expand, so with the cooling and heat of night and day, it will probably cause stress from the constant change. So I guess it comes down to the strength of the material. Obviously rubber bands aren’t near as strong as plastic. TBH, I could also be compleely wrong about this. I’m just going off of what I can find and my basic High School knowledge of physics and thermodynamics.

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I’m always terrified that the sun will deteriorate my minifigs, so I do my best to keep them out of it.

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It really does, if you hold them too long.I have mostly seen it on white pieces, which turn into a yellowish-tan.

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Sun decay really only happens on white bricks, at least on a visible degree.
Keep in mind that it takes a few hundred degrees of heat to fully melt these guys.
Your minifigs might become a little dull in the sun, but that’ll be due to several hours of exposure. You should be fine as long as you don’t leave something out there.

Sunlight will cause anything to decay in time.