Resin questions: useful life, reuse, separation, water toxicity, storage time, etc

I copy and paste here a post i made to kickstarter and feel was not answered that I had posted directly to Rinnovated already a few days before (I have added numbers on the questions):
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1.Maybe I have missed this somewhere but what should we think about reuse of unused resin and water that has been used in a peachy print at least once? I think this tells us how exact we need to be to reduce the amount of scrap material between printing runs.


2. Roughly how much useful life do you all think the remaining resin has once the resin is put together with the water in your current design? hours? weeks?


3. According to the makerjuice subG spec and MSDS which I understand can be and has been so far used (? could be subG+ being used but there are no data sheets for the + that I find) :


ref MSDS subG:
Hazard Statements:
Causes serious eye damage
Causes skin irritation
Harmful to aquatic life with long lasting effects
May cause an allergic skin reaction


ref : Technical Data sheet SubG:
Storage:
Store in a tightly closed, opaque container in a properly vented storage area under dry conditions away from heat, sparks, and open flames. Shelf-life is 6 months from receipt.


4. First, can you tell us where you think the peachy resin will/could differ on these?


5. It seems the resin makes the water toxic as it states "Harmful to aquatic life with long lasting effects".. so the water I am guessing should in all likelihood NOT be poured down the drain? the other things regarding eye and skin as well as allergic reactions are at least to me expected but it tells me I do not want to do this in my home and maybe with some kind of fume hood? if so I would be thinking about a much more sealed design (the laser sealed within the lower resin container to reduce fumes and possible irritations.


Regarding storage then it states "Store in a tightly closed opaque container". This also tells me that I probably do not want to leave out the resin within the open and transparent peachy as being shown but again a more sealed design.


6. But the text continues with "under dry conditions".. so then it seems that putting the resin with the water is already limiting its useful life and limiting the ability to reuse it? Then If reuse is possible I would guess you would want to separate the resin and water as much as possible but just how far one may want to go will depend on the effect of the water on the resin and vice versa. Any insight into this would be great and any suggestions on how you now think one would separate?


7. It also mentions about ventilation as well as the heat sparks and open flames.. to me this seems like typical chemical safety not so impacted by the peachy's innovative design. But if I were to integrate the laser into the resin container to reduce toxicity while it was working I would probably make it removable as well?


8. Finally this storage text also states "Shelf-life is 6 months from receipt". 6 months is not a really long time it limits perhaps how much material one may stock up on to reduce waste. What happens after 6 months? have you tested material that is more than 6 months old?


So far this leads me to think that the containers for the peachy would be best suited to maximize the resins longevity and to manage the contaminated water while reducing toxicity in the environment if they were opaque and resealable with the laser somehow integrated or suspended in the resin container. I am thinking depending on the useful life of contaminated resin that between prints one could contain in one the mostly separated reused resin and in the other the contaminated water and either.



your insight into this is much appreciated.

To add to your questions (as oppose to making another thread) I would like to ask if there will be a EU distributor of the resin. Import tax will be horrible for us Europeans.

I am also interested in all of these. I would also like to know if there were any available, or plans to develop, a filter that can separate the resin from the salt water and if it can be integrated into the printer build itself.

I don't know much about the resins but these are widely used in industry. Using Google I even found that they are developing resins which can be used medically for body parts.
They seem to be toxic to various degrees before curing and not much after curing.
I found this good guide to safe storage and use: http://www.3dsystems.ru/global/files...shg.pdf‎
This should answer a lot of your questions.
Instead of pouring uncured material down the drain which may be toxic, they recommend setting it out in the sun to cure and then it can be safely disposed of. Also, oxygen exposure is considered good since it soaks up free radicals which degrade the material.
Apparently old material gets thicker and this may cause problems with use.
Lots more good information on resins if you use Google stereolithography resin toxicity.
You can also add fillers and colors to the resins.
I think the whole subject of resins warrants a separate discussion since it is beyond the printer design.

There seem to be a lot of questions, so I'll answer some as I can. If you have specific questions, please email me as I do not keep up with this forum and cannot answer all questions posted on it. Emailing me is the only sure way to get an answer.

* Resin can be reused until it is gone, or there isn't enough to build a layer on the water surface.
* The resin does not mix with the water. They are pretty much oil and water. AFAIK, the resin could sit on the surface of the water for as long as the resin remains stable (6+ months).
* PP resin will be similar with a conservative 6 month life from shipment. Realistically you can probably get a year out of it, in the right conditions.
* The resin itself is toxic to aquatic life, just as pretty much any chemical dumped in water would be. However, as the resin in the PP design does not MIX with the water, it should not pollute it and so the support water should be fine to dump. I would recommend setting the resin/water mixture out in the sun. Any resin left in it will cure, which will make it inert. The rest of the water should be fine to drain/pour out.
* The resin has very little smell and no "fumes" really. MSDS are pretty much worst case scenario. Just like you wouldn't spray Windex in your eyes and expect it to be fine, neither should you put any printing resins in your eyes or frequently allow it to sit on your skin.
* Ambient light from the sun will cure the resin, as will close incandescent bulbs. That's why it needs to be stored in the container.
* Photopolymers have a natural tendency to polymerize. They have inhibitors in them to prevent this, but it will be used up over time. This limits their shelf life. If you don't think you will use a given amount in 6 months, my best recommendation is don't buy that much at a time.
* We don't have an EU distribution partner yet, but we're looking into it. We currently ship to almost every EU country, and most others in the world as well. If there are import taxes or anything like that, it will depend on your country.
* I don't know how Rylan and the team plan to handle the separation of the resin/water, but it is pretty easy to separate it with a funnel with a valve on the bottom. As the resin will float, you simply drain the water out from underneath it, and then pour the resin back into the resin bottle.

I think the six month shelf life is probably for the best, because it forces people to use it or lose it! If the resin could be stored indefinitely, I would probably squirrel it away and hardly ever make anything.