"Leech" vs "leach".
Originally Posted by LusiferSam
What makes you think LEGO bricks don't use plasticizer? They're extruded or molded parts which generally requires a plasticizer to avoid cracking during temperature shifts or to cracking during the manufacturing process. Just because they are hard plastic doesn't mean they didn't require plasticizer, they're just not using as much, and not using a phthalate - the plasticizer that's been in the news so much the past few years. They absolutely use plasticizers or else they couldn't be molded or extruded into the shapes they take, especially the high-tolerance shapes that LEGO parts specifically conform to.
Well I guess we'll have to agree to disagree on this. Most figure torsos are a styrene type plastic, as to whether its ABS or some other type I'm not sure on. ABS is pretty stable plastic. The legos I have from the 60's some very little sign of aging other than some discoloration. Now Lego brick don't have any plasticizers in them as far as I know. If Hasbro has been using ABS in the torsos I don't believe there would be much use of plasticizers.
They say they use ABS and PVC. I would say your uses seem correct, torsos get ABS while limbs and heads get PVC.
The limbs are a different story. Those I believe are made from PVC. PVC is normally a very hard plastic. But most limbs on SW figures "soft." The plasticizers give than nice pliable feeling to them. PVC isn't a stable as ABS, particularly with the addition of a plasticizer. It's the limbs that have me most concerned for aging.
As for the plasticizer, I talked to my step-dad, he's a manufacturing engineer, at length about this issue on Saturday. He said that with these materials, the plasticizer cannot leach out, once mixed together with the base material, the plasticizer molecularly bonds with the original material to make the new material, that they combine to make "the plastic". Any plasticizer that comes out isn't leaching from the material, but unbonded excess. The only ways a plasticizer will leach out is if the molecular bonds of the base material break down either from the material exceeding its lifespan or if another material is breaking apart the molecular bonds, and then you have total breakdown of the product, it doesn't just get brittle, it crumbles apart.
Considering we've ruled out light exposure as the cause of the yellowing in these figures, and I can rule out temperature extremes for mine, that leaves chemical influences. In this case almost has to mean impurities in the original mix, my step-dad says that a lazy individual factory machine runner (I forget the term he used for this person) might produce these issues by improperly mixing in the dyes or flame retardants or other additives just in that batch, and that these are what's breaking down in the color issues showing up only in SOME of the figures. It's from not being properly bonded to the material in the initial manufacturing process, causing early rapid tinting or breakdown of the dye.
I highly doubt the lifespan is set under 10 years only because of storage, shipping, and storage times before it gets into the consumer's hands. I can see 5 years before getting into the customer's hands being perceivable, which would leave just 5 years before the material is intended to break down. Hasbro is extremely concerned with customer safety with their products, they're the best-testing major toy retailer to come out of the recent toy scandals. I can't see them arguing for less than 15 years from factory to disuse on those merits alone.
So what type of time scales are we talking about. I would say in the "normal functional lifespan" of a toy you aren't going to see any thing. What's the "normal functional lifespan" of a toy? I'd say under 10 years. Most people grow out of their childhood by the time they're teens. We here are the odd balls in that we have acquired and hung on to our toys for so long. In 60 to 70 years, the time when most of us should be pasting our collections on, I'd say you're going to see I wide range of age related effects. A lot of it will have to do is storage and display.
Maybe we should pose this question in Q&A, another site asked about the lifespan of the figures in regards to storage, but not to intended use, so they didn't get a specific answer since Hasbro doesn't concern itself with collector storage.
Considering that ABS and PVC products can be made with operational lifespans measured in generations (look at some PVC plumbing from the 1930s that is still holding up today), it seems unlikely that the lifespan on on figures would be focused as short as 10 years, that would be weaker than a plastic milk jug (in terms of permeability).
Of course, there are different lifespans to consider, colorfastness may be a tertiary issue to them. On the other hand, I will point out again that with POTF2 figures, we've got 15 year old Hasbro-manufactured product holding up fine and 32 year old Kenner-manufactured product holding up too.
I just grabbed 3 Ep 1 Battle Droids, 1 "clean" and 1 "dirty" variety (for those who don't remember, there were 4 paint scheme varieties) and 1 from the STAP, and they are indeed tacky after a decade in simple loose group storage. But here's the thing, these figures haven't lost any pliability whatsoever, and the STAP one is less tacky than the others despite being the same (it was displayed but sat under some papers after losing one of its missiles). They've also all held their colorfastness, in fact both pliability and color seem better than I remember them originally being. So this could be excess plasticizer that wasn't bonded to the plastic to begin with, it could flame retardant, it could even be mold-release oil, but I don't see any signs of the plastic breaking down at all, which is what would happen if the surface of the material were leaching its plasticizer. You'd see a loss of pliability and you'd see cracking.
So I check a bunch of my figure last night. I didn't check everyone but a group of them. The figures I personally worry the most about are the Battle Droids. The limbs are very thin, very rubbery and in general they're white figures. I was highly bothered by the fact the all of the Ep 1 and one of the POTJ Battle Droids were all a bit tacky feeling. That tells me the plasticizers are leaching out and I need to store these figures different. If you Battle Droids are on display they be outgassing better than mine or a tin layer of dust might be masking the tackiness. In any case this won't the first or last indecent of sticky modern figures.
If plasticizer were leaching out, those rubbery Saga battle droids would be hardening up over time, but they're not, they actually seem to be getting worse, more rubbery. As a thermoplastic, that means either they are warming up beyond their set temp, or they are suffering from gravity's effects more. I can again attest to mine not getting significantly hotter.
I suspect this is not an incident that is leading to "the beginning of the end", as it were, just excess additives leaching out over time, not a breakdown of materials. I have found other Ep 1 and earlier figures that are tacky, and I've even found more POTF2 figs that have had color issues (the shoulders on my gray Ugnaught are showing a little fading), but when you wipe away the tacky surface, they perform the same as new.
In fact, I'll do a test. I've wiped away a very tacky surface on one of those '99 Battle Droids, on the thigh. Now I've pushed my thumbnail into the plastic (without lateral movement) until it has left a mark, and performed the same action into a Clone Wars Battle Droid's thigh until it left a mark. They took roughly the same amount of pressure to mark on the surface, the very area where a leach of plasticizer should have broken down the plastic soonest and been more brittle or even crumbled away. I did the same test with their forearms, and got similar results. I don't have a durometer, so this is the closest test I can perform, but it also gives direct tactile results and I can tell there is no cracking where I cut down into the part.
I think what's going on is standard outgassing, not leaching, that normally would just evaporate into the air, like how "new car smell" eventually goes away, but either by storing the figures in areas with poor air movement, or suffering exterior surface contact through dust or what have you, the outgassing has built-up the excess that normally would have evaporated, causing to condense on the figure's surface. In fact, the tackiness has already started to subside on those battle droids I left on my desk about 20 minutes ago when I started my reply.
Also, tackiness isn't really a good sign of problems in of itself, I've gotten a lot of new figures the past few years from other companies like Mattel that are tacky straight out of the package.
Getting back to colorfastness, my step-dad says that white is pretty much the hardest color to get plastics to take, it's very easy to mess that up. Most of my yellowed figures are white - Stormtroopers and R2's body are my main examples of yellowing. The clear stand on my STAP is also yellowed some, and it doesn't seem to be a UV issue since the yellowing appears uniform (with regards to thickness) even where it was partly covered by the STAP collection point. Clear plastics also seem to show the most color issues over time in other Hasbro lines, especially Transformers. Does that mean they're leaching plasticizers, or is it something else? The clear parts usually start brittle - I've had them break down upon opening - and never have tackiness that I've heard about, so I don't think it's a plasticizer issue in regards to leaching. And they are clear, which means not dyed, so it's not dye breakdown. That leaves flame retardant aging, mold release oil (assuming they put it in the mix and not just sprayed down on the mold after a few runs), or another additive that is aging, tinting, or breaking down.