Re: I would like to know why they turn yellow.
Posted by Lula on November 22, 2019, 9:56 pm, in reply to "I would like to know why they turn yellow."
From what I heard, it has to do with the quality of plastics Integrity used back in the day. Here’s a quote from BlytheLife.com that better explains what I’m guessing was a contributing factor to the yellowing issue. |
“ Discolouration of plastic can be uniform or in patches. This is because sun/UV exposure may be only on one side, and it also has to do with the quality of the plastic. If the components are not evenly mixed throughout during the manufacturing process, then the plastic will discolour (or degrade) in patches because not all areas of the plastic are equal in their components. This can be especially true for more vintage toys because of the standards in quality and the science that was used to produce polymers at the time”
The issue with not properly mixing the components sounds like it would readily explain why some batches of the older dolls haven’t yellowed and some have. I’ve got earlier IT dolls who have just one leg that’s yellowed or separate body parts that have. It would make sense if they used one batch of plastic to cast a batch of certain body parts and used a new batch to cast other body parts. You would have certain places that would yellow while the others wouldn’t. I imagine they’ve gotten better at mixing AND are using higher quality plastics now.