
New, slippery toilet coating provides cleaner flushing, saves water - howard941
https://phys.org/news/2019-11-slippery-toilet-coating-cleaner-flushing.html
======
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](https://www.spotlessmaterials.com/shop)

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

~~~
johnpowell
Time to get gross here.

I have been dealing with neck/mouth cancer for a while and using a feeding
tube for about half of my calories. My movements, depending on the alignment
of the stars resemble the mortar used to join cinder blocks together. It is
explosive and sticks to the bowl. I can flush ten times and it doesn't budge
and I have to manually get in there.

So I am going to try this. It is cheap enough and even if it helps a little
will be a huge quality of life improvement.

Three months into chemo it wasn't great dealing with every trip to the
bathroom being a chore. And combine that with the fact that my immune system
was basically non-existent. Lingering fecal matter was a health risk.

You might want to consider marketing to radiologists, oncologists, and
nutritionists. Tons of fellow tubers out there.

~~~
shortandsweet
Try a parachute. Put some to down in the water before you let loose.

~~~
johnpowell
Sadly, we are dealing with a Jackson Pollock situation.

~~~
cerberusss
You sir, are an ace. I wish you all the best.

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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.

~~~
HorizonXP
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.

~~~
gpm
I do live near the great lakes, but my comment about not worth optimizing is
really just that as a percentage of global water usage toilets are tiny
(compared to agricultural and industrial. Agricultural is 80-90% in the states
for instance). Optimization only really makes much sense where locally that is
false.

There are definitely plenty of deserts in the world though, so it's not much
of a nitpick.

~~~
ac29
> Agricultural is 80-90% in the states for instance

Actually, irrigation uses less than 40% of water in the US. The largest use is
thermoelectric power generation. [0]

[0]
[https://pubs.usgs.gov/fs/2018/3035/fs20183035.pdf](https://pubs.usgs.gov/fs/2018/3035/fs20183035.pdf)

~~~
hvidgaard
The majority of that water is surface water - that is only used for
consumption if there is no suitable groundwater reservoir, and it is returned.
So the environmental impact is less that irrigation as that removes the water
from the source.

------
haklriueo
> When we put that coating on a toilet in the lab and dump _synthetic fecal
> matter_ on it

This reminds me of a documentary about toilets, and one factoid was that
American toilets were much worse at flushing than Japanese ones, and would
block more frequently, and it turns out that American ones were tested with a
small standardized rubber ball, while Japanese ones with the real deal,
including big productions.

~~~
safepants
I watched a video from This Old House where they toured a toilet factory. They
used Miso paste in a condom to simulate fecal matter.

~~~
TheRealWatson
"7 links of miso"... I remember that every time I buy sausage links. Gross
haha.

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

~~~
TeMPOraL
Honestly, I do. I've placed a bucket in the sink to capture waste water from
washing hands, which is then reused for flushing the toilet after
depositing... liquid contents in it. It saves a bit off the water bill and
also made me realize just how much water I use up when washing hands...

Of course I hide the bucket when guests come, it's too weird a thing - but in
all honesty, I've wished many times for a system for capturing sink & shower
water in a tank, for use in toilet. The standard practice is inefficient.

EDIT: I didn't know the term "greywater" before, and after reading
[https://en.wikipedia.org/wiki/Greywater](https://en.wikipedia.org/wiki/Greywater)
I'm having second thoughts about my scheme. If the city is actually treating
greywater and water from toilets separately, then I guess it makes sense to
let the sink water drain. But then again, that's a huge _if_. I'll need to
take a closer look at my indoor plumbing and read up on the water treatment
scheme in my area.

~~~
toast0
As of now, very few buildings have separate grey and black water plumbing. In
the event that you did have separate plumbing in the building, you would need
separate plumbing in the street as well.

Unless you live in a very water constrained area, it's pretty unlikely. In the
US, plumbing for reclaimed water is available in some areas (purple pipes),
and seems like an easier intervention, it's often used for landscape
irrigation, which has easily accessible plumbing to retrofit. It can be used
for toilet flushing as well, if that is plumbed separately from other fixtures
in the building.

~~~
joncrane
Can you irrigate with water that has detergents in it though?

~~~
toast0
Yes, depending on the detergent content. Reclaimed water is usually water
that's been treated for pathogens at the treatment plant, but hasn't had been
through all of the post-treatment cleansing required before discharging into
waterways.

------
Pamar
I came here just to say that - if memory serves - this was mentioned in The
Mote in God's Eye by Niven & Pournelle: humans have contacted an alien race,
and the aliens suggest some improvements to the human technology on display on
the spaceship. Among these, a "frictionless material" which one of the human
engineers points out "will save lots of water on arid planets and also on the
spaceships themselves".

(During the exchange with the aliens who live there, one

------
tigerlily
What is this stuff made from? I hope they think of the fish, that's all.

~~~
stephenr
Raw sewage probably isn’t that great for fish either.

~~~
adrianN
Raw sewage is well known to decompose in the environment into harmless things.
Unlike the majority of chemicals we invented in the last 100 years or so.

~~~
Tharkun
Errr.....no? Human waste in water is a major cause of disease. Sure, a turd or
two won't be a problem. And sure, it'll decompose. But all kinds of pathogens
remain. There are billions of people, and as the eponymous book says: everyone
poops.

~~~
adrianN
People have been pooping for millions of years without filling our oceans with
poop. We have been creating new chemicals for a hundred years and have created
a huge waste problem. The last time pooping had a big impact on the global
ecosystem was during the Great Oxygenation Event, afaik.

------
michaelt
_> 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?

~~~
dwyerm
...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?

~~~
michaelt
Merely that a coating that retains total choice in colours is more flexible
than one that limits the range of colours possible.

And presumably that's part of the contribution here - a nonstick toilet that
doesn't look like the ones you get on planes and trains already.

Also, the current fashion in my country is for white toilets - you go to a
bathroom showroom, ~95% of what's on display will be white. A design that
doesn't require a change in fashions is simpler than one that needs tastes to
change.

------
papreclip
More chemical waste in our water system. There's nothing wrong with the amount
of water we currently use to flush our toilets. Now, there's something to be
said for a cleaner flush, but another solution to that problem - with many
other benefits - is to consume more fiber

~~~
catalogia
> _" There's nothing wrong with the amount of water we currently use to flush
> our toilets."_

That depends entirely on where you live. Depending on the local situation, you
might have almost no fresh water, way too much fresh water, or just the right
amount of it. In these sort of conversations people often seem to forget that
their local conditions are not universal.

------
basicplus2
I find a toilet brush works just fine..

Less water in the sewer is only going to create problems for the flow rates
further down the line, Possibly blockages in the pipe on your property.

and i would prefer not to put silicone (if that is what they are using as it
is "like hair conditioner") as some silicones can take 400 to 500 years to
break down

------
thomasjudge
It seems like there was something similar a few years back that got a lot of
press as solving the ketchup-adhering-to-the-bottle-problem

[https://www.bbc.com/news/science-
environment-39030055](https://www.bbc.com/news/science-environment-39030055)

------
mkonecny
Are we sure this is not a step backwards? We woild benuaing.less water, but
filling our lakes with lubricant?

~~~
sfsafs
From a comment above from the developer, it seems this stuff (particularly the
second coating) is akin to hair conditioner.

------
aaron695
Since it seems like HN are just Luddites afraid of something new or don't
understand the product, lets spell it out.

Cleaning a toilet sucks, this product will sell well if it works as claims and
makes it easier. They will get $, you will not.

Cleaning public buildings is a huge cost that takes manual labour, if this
product has a good price point and works as they say, it will save $100 of
millions yearly.

No one in the real world actually cares about saving water in the home and
being afraid of new things is boring.

The only question is "The researchers also predict the coating could last for
about 500 flushes " In the past the issue stopping these products being
everywhere has been the fact they wear out quickly when abraised.

------
glofish
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 scientific breakthrough as "saving money on water" is ridiculous. We
already have a simple solution that works.

~~~
tenebrisalietum
> 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.

~~~
war1025
Something I have wondered a couple times when this comes up: When people say
"Water bill", do they mean solely water, or water + sewer?

Where I live, the two are bundled, and the total bill is also higher than our
internet bill. (~$100 for water vs $75 for internet)

I live in Iowa, which doesn't have Great Lakes levels of water lying around,
but we also have no shortage of the stuff.

~~~
JoshTriplett
Yes, they're often combined, on the basis that it's easier to measure water
usage than sewer usage and the latter is presumed to be proportional to the
former.

~~~
war1025
So when people say "my water bill is higher than $X", do they mean the
combined bill? Does the town I live in just have abnormally high water prices
for an area without water scarcity, or is water just artificially cheap in
other places?

~~~
stevehawk
Regarding the former - Yes. It's basically something like this:

line 1 - Water usage = X line 2 - Sewage usage = X * modifier

My monthly water usage is usually something like $20 worth, but my "water
bill" is usually around $60-$65 when combining water + sewage (2 adults, $ =
USD).

------
toomuchtodo
@birgitt: Instead of a labor intensive process of spraying and paper or cloth,
could you not include the lubricant in a separate reservoir and apply a bit
with each flush, avoiding the need for a manual process? Or perhaps have an
automatic cycle where the bowl drains, the lubricant is applied, and then
water is supplied to refill the bowl after a period of time has elapsed (if
necessary)?

It seems manual application is likely to slow adoption IMHO. If automated,
seems like a slam dunk for heavy use/commercial/public applications though.

~~~
ghostbrainalpha
Manual application is gross, but adoption could be quick if it is focused on
companies that use janitorial services...

Honestly how many Hacker News readers read this story and thought about
ordering the product and having their weekly cleaning person be in charge of
applying this even monthly in their homes?

------
trynewideas
I cannot wait — I cannot, cannot wait — for my cat to _finally_ fall in

~~~
TheHypnotist
I've got a wheel of cheese with my name on it.

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ARandomerDude
Reminds me of an old plumbing trick: got a really stuck toilet? Pour a little
dish soap into the bowl. It makes everything slippery so dislodging debris is
much easier.

~~~
Nextgrid
Unfortunately I recently gained the experience to confirm that this does not
work. It wasn’t even “really” stuck and yet the dish soap did nothing (nor
chemical drain unblockers), only the good old plunger did the trick.

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iamtheworstdev
All of the money people save on their water bill can now be put aside for
their annual call to the plumber as you'll likely end up clogging your pipes.
Not enough water in every flush means you'll end up with a blockage at some
point because the feces was never irrigated out of your pipes to the street.

------
ttul
Quick link to the order form:
[https://www.spotlessmaterials.com/store/p14/Coating_Kits.htm...](https://www.spotlessmaterials.com/store/p14/Coating_Kits.html)

------
lazyjones
Large, old cities already have problems with their waste canals clogging
because modern toilets and showers use too little water. I wonder how this can
be solved in the future, perhaps by coating the canal as well?

~~~
new2628
Surprisingly, at the same time they often outlaw channeling rainwater (coming
down from the roof) into the wastewater system, although that seems to be a
solution to several problems at once.

~~~
lazyjones
Rainwater often causes the opposite extreme with the same result, i.e. canals
overflowing with water (rain = a lot of water in a very short time), which
means they're blocked too.

------
vfinn
There are solutions that help you save water by requiring you to flush only
when taking a dump (by preventing pee from smelling and hiding it). I don't
remember the exact products.

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RenRav
This kind of thing seems a hassle to do manually. As a feature on a smart
toilet though...

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jobseeker990
Why not other applications? Boat hulls, water slides, dishes, cookware?

------
aitchnyu
Are there existing examples of commercial (ahem) goophobic coatings?

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dehrmann
Haven't airplane toilets been doing this for a long time?

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Jaruzel
PSA: Do NOT put this stuff on the toilet _seat_.

------
honest_tovarich
How satisfying to watch that video....

