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New, slippery toilet coating provides cleaner flushing, saves water

phys.org

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Re: New, slippery toilet coating provides cleaner flushing, saves water

#11

Post by dwyerm »

michaelt wrote: post #3

> The researchers also predict the coating could last for about 500 flushes in a conventional toilet before a reapplication of the lubricant layer is needed. It's a neat idea - especially the fact the bowl remains white, unlike a coating of PTFE or similar. I wonder if it's an idea they can develop further into a permanent coating?

...which is strange, since PTFE is naturally white. I think we've become used to seeing it on silver and grey frying pans.

But that said, what's wrong with a dark-colored toilet?

Re: New, slippery toilet coating provides cleaner flushing, saves water

#12

Post by glofish »

throwaway5752 wrote: post #8
glofish wrote: post #2

Unpopular opinion warning! Getting people to save water is one of the simplest things in the world! Water is the cheapest material that people have access to. It is so cheap it has been devalued to the extreme. Fill a backyard pool? That'll be less than $100... Raise the price a little bit, all of a sudden people will use less water, they won't even notice any effect and have the same quality of life. Framing a scien…

Water should be cheap, it's less expensive overall that society dealing with poor water sources (healthcare, developmental). There should be a two tier price system. Cheap up to a threshold, then expensive beyond that, like with mobile internet. And even then, tech to reduce waste is great and should be celebrated and is not mutually exclusive.

I think saying here is toilet where your poop does not smear is a much better slogan.

Re: New, slippery toilet coating provides cleaner flushing, saves water

#13

Post by tenebrisalietum »

glofish wrote: post #2

Unpopular opinion warning! Getting people to save water is one of the simplest things in the world! Water is the cheapest material that people have access to. It is so cheap it has been devalued to the extreme. Fill a backyard pool? That'll be less than $100... Raise the price a little bit, all of a sudden people will use less water, they won't even notice any effect and have the same quality of life. Framing a scien…

> Water is the cheapest material that people have access to.

You don't live in the American South. I actually suspect you live near one of the Great Lakes where the water is dirt cheap. My water bill is higher than my Internet bill.

Re: New, slippery toilet coating provides cleaner flushing, saves water

#14

Post by gpm »

500 flushes is less than a year for a toilet used twice a day (say before and after bed), I hope that coating is cheap, easy to apply, and doesn't create substantial pollution either as it is created or used.

I hope the sewer system doesn't need to just add water as a result.

Toilet water use doesn't seem like a big enough contributor to the problem that it's much use optimizing it in most places. But there are probably some where water is locally scarce and it makes sense.

Re: New, slippery toilet coating provides cleaner flushing, saves water

#15

Post by birgitt »

Hi Everyone! Birgitt here from spotLESS Materials -- we are commercializing this technology and some of the authors of the Nature Sustainability paper are part of our team. I'll try answering some of the questions I'm seeing. Would love to hear your feedback!

Check out our products at: https://www.spotlessmaterials.com/shop

Check out the full research article here: https://www.nature.com/articles/s41893-019-0421-0#citeas

Edit: Let me answer a few of the common questions here:

1. Is it easy to apply? We designed our coatings to be applied in minutes with just a spray bottle and a paper towel/cloth.

2. Regarding durability: Our coating consists of two parts - the first part is the formation of a nanohair layer, which is permanently bonded to a substrate (e.g., toilet surface or glass). This layer itself is very liquid-repellent and sludge-repellent and does not require replenishment as it is permanently attached onto the underlying substrate.

The second part is the lubricant, which is infused into the nanohair layer (like a nanoscale sponge absorbing the lubricant). The combination of the lubricant and the nanohair make LESS coating super slippery against liquid and sludge-like substances. The lubricant layer will wear off over time depending on the frequency of use. For typical use in a toilet environment, the lubricant will need to be replenished after ~500 toilet flushes and can be reapplied by a simple spray process.

3. Regarding the environmental friendliness of our coatings: Our product is based on silicone. It has been shown in the scientific literature that silicone can be decomposed naturally in soil within 4-7 days. It breaks down in silica, water, and carbon dioxide.

Ref.: Graiver, D., Farminer, K. & Narayan, R. A review of the fate and effects of silicones in the environment. J. Polym. Environ. 11, 129–136 (2003).

Re: New, slippery toilet coating provides cleaner flushing, saves water

#16

Post by pm215 »

michaelt wrote: post #3

> The researchers also predict the coating could last for about 500 flushes in a conventional toilet before a reapplication of the lubricant layer is needed. It's a neat idea - especially the fact the bowl remains white, unlike a coating of PTFE or similar. I wonder if it's an idea they can develop further into a permanent coating?

Yeah, 500 flushes is not really very many. I live alone and I reckon I flush the loo at least three times a day, which would mean the coating needed reapplying every six months. If you're a family then it's probably heading down towards every three months. If this spray can be re-applied by the end-user and isn't too expensive that's annoying but just about OK I guess. If it needs a technician visit and/or it's an expensive coating then it's not practical. An order of magnitude more flushes between recoatings would definitely be better...

Re: New, slippery toilet coating provides cleaner flushing, saves water

#17

Post by HorizonXP »

gpm wrote: post #14

500 flushes is less than a year for a toilet used twice a day (say before and after bed), I hope that coating is cheap, easy to apply, and doesn't create substantial pollution either as it is created or used. I hope the sewer system doesn't need to just add water as a result. Toilet water use doesn't seem like a big enough contributor to the problem that it's much use optimizing it in most places. But there are proba…

I tend to agree, but I (and maybe you) live in the Great Lakes region where water is abundant and cheap. Optimizing water use just doesn't seem worth it.

But I can totally see this coating helping in regions like India, who have a real problem with open-air defecation.

Re: New, slippery toilet coating provides cleaner flushing, saves water

#18

Post by xiphias2 »

gpm wrote: post #14

500 flushes is less than a year for a toilet used twice a day (say before and after bed), I hope that coating is cheap, easy to apply, and doesn't create substantial pollution either as it is created or used. I hope the sewer system doesn't need to just add water as a result. Toilet water use doesn't seem like a big enough contributor to the problem that it's much use optimizing it in most places. But there are proba…

The additional maintainance maybe doesn’t worth it for homes, but clean toilets would be important in commercial space.

Re: New, slippery toilet coating provides cleaner flushing, saves water

#20

Post by Scoundreller »

hanniabu wrote: post #19

Why don't we use grey water to flush toilets? It can use water either from the bathroom sink or shower.

I understand Hong Kong uses seawater to flush toilets.

The chlorination process is simple: just pass some current through the salt and voila, chlorine.

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