that's interesting, thanks for the insight -- I was aware of thermal's darkening but unaware of it's speed. I'll leave one out in the sun tomorrow, if I can have ~4hrs with it I'll be chuffed

And, of course, as you said, aviate navigate communicate first :)

Thanks!

Yeah I've been "burned" by thermal receipts before. Had a receipt in my wallet. 30 days later, the thermal print completely faded.

Had to dispute with credit card company over that one. Wasn't fun.

Makes me wonder if "you need a receipt to claim warranty" is intentional like that.

There's a few apps that can organize / OCR receipts for you, if a photo of a receipt is adequate. I don't actually know any and I may be talking out of my ass but err. I'm sure there are!

Over here in Poland, companies usually require a "proof of purchase", which can be a receipt or an invoice. As a buyer, it's up to you which one you want to receive[0]. There's a special kind of pseudo-invoice called "personal invoice", which is like a VAT invoice except you don't need to be a company or provide a tax ID for it. This is the one you want in any scenario when you expect to hold on to the proof of purchase for longer than it takes to reach the nearest trash can - its killer feature is that it can't possibly fit on a thermal paper receipt[1], so you get it printed out using regular, durable means, on regular office paper (and/or e-mailed as PDF).

--

[0] - On-line you usually get to pick at check-out, off-line you usually have to ask before paying.

[1] - Technically it could, but it would be quite an achievement, and it's sufficiently non-standard that nobody bothers.

>and it's sufficiently non-standard that nobody bothers

Some gas stations do!

Also, most thermal paper is high in BPA/BPS.

https://www.pca.state.mn.us/business-with-us/bpa-and-bps-in-...

General Aviation still uses lead in their gas, despite it being shown several times in enormous nationwide studies consistently to not be necessary, and often simply requires more cost in maintenance (lead builds up on spark plugs causing a lot of issues).

So environmental impact isn't high on their list already, and this BPA issue is very likely going to be completely ignored by anyone in that field.

Yes, but the avgas lead situation is primarily a problem for the people behind/under the aircraft, not inside the aircraft.

You still have to fill it up by touching and breathing in the fumes while pumping it into the tank, so not exactly, but you're right that it does affect others as well.

dunno about the evidence, but I kinda figured post-combustion lead is more atmospheric than pre-combustion lead. Elemental lead doesn't really absorb through the skin (and gas doesn't evaporate too well at low temperatures) as far as I know.

Lead added to fuel is in the form of an organic compound, so I'd expect the opposite effect. Obviously there's more distribution post combustion, but from a bio-availability standpoint spraying tetraethyl lead around in equivalent quantities would be a much more severe problem.

Naively (without looking at data for concentrations in various environments), I could buy that people regularly handling / being around leaded aviation fuel are worse off than those breathing the (dilute) exhaust products.

I realize this is an anecdote, not data, but after flying my own plane for 5 years and getting >500 hours of flight time, plus soldering off and on for 30 years with leaded solder, my lead levels were fine at my last physical. I don’t drink avgas or anything, but don’t take precautions other than attempting to avoid getting it on bare skin.

We got one of them fancy lads what drinks the jet A, boys. Thinks the 100LL ain’t good enough, no doubt!

:)

From first look, yes, and for more or less modern engines, which really don't need lead.

But for planes, normal age more than 20 years, even exist workhorses with 70 years.

They have very old engine technologies, some literally spread gas on ground (use lead in it to lubricate valves, which are outside, like on old star engines). So even when you walking where such plane was, you will gather some lead.

Guessing parent was referring to the practice of heating BPA-laden paper in the near vicinity of commercial food-prep

Yes the problem is recertification. This is why GA also still uses engines developed in the 50s with associated tech.

We are losing out on so much.

We are yes... Turbodiesel seems to be the answer even though a rebuild is not possible so they need a replacement very often :( On the other hand the unleaded gas engines like Rotax seem to be super reliable in the ultralight category, they are just not certified for real GA. I would imagine that slightly scaled up they could be a real workhorse.

Or perhaps a really small turboprop. I've seen really tiny jets so why not stick a prop on it (because jets are too inefficient at low altitudes). Might help with noise too.

There's so much innovation we could be taking advantage of :'( But we're still using engines designed in the 50s with lead (replacement) and manual choke/mixture that cars have deprecated 30 years ago.

Banned in EU since 2020: https://eur-lex.europa.eu/eli/reg/2016/2235/oj

The first few months of 2020 were quite busy: they gave us blue receipts, covid, and brexit.

I remember this being discussed on HN before. It felt a bit like "till receipts are killing us" which in the context of someone flying a 40 year old plane with noted defects might not be a primary concern.

I wanted to buy a thermal printer myself but couldn't find a definitive answer or evidence of the BPA part being a risk. I got one that uses BPS instead - other papers also raised concerns about this, but again I couldn't find direct evidence of health issues associated with the handling of till receipts.

I decided as the receipt printer will be used infrequently and I have been handling till receipts for the last 4 decades I wouldn't worry about it. BPA is also present in food cans and plastic bottles - the link you sent states the concentrations are higher in receipts - but at the same time I don't intend on eating the receipts or rubbing them into my skin.

Generally I'm quite cautious about chemicals in everyday life, I try and reduce the amount in our house using natural products for cleaning for example.

At the same time we're constantly surrounded by toxins so I often find myself having to do this sort of rationalisation to avoid worrying about seemingly everything all the time.

Thanks, I wasn’t aware of this and was just about to buy one of those super cheap thermal printers you find on AliExpress. That’s less junk filling up my house.

Worth reading this Brother study on thermal paper degradation: https://www.anixter.com/content/dam/Suppliers/Brother/White%...

Worth looking at Figure 3 showing how different samples of thermal paper have vastly difference reactions to high temperatures.

Once had a set of Aliexpress plastic water carriers take 6 months to arrive to me during COVID and it when it arrived, it seemed like the plasticizers from the carriers (or the factory?) severely degraded the thermal shipping label.

We use high temperature paper (170F, 20% dark at 6mJ/mm²). It will not turn dark left many days in a truck dashboard in the summer in Texas. I once found a stack of 7 year old receipts and they were completely readable.

True. And for some reason they always want to put the kitchen printer right under the heat lamps.

Yeah in my experience you need a 'thermal transfer' printer instead. Uses a ribbon to transfer the ink rather than treated paper.

A lot of manufacturers make the same printer in thermal transfer or direct thermal models.

I used to develop smart parking meters, and we used thermal printers in those. You can get paper that tolerates high-temperature environments like the dashboard of a car on a hot sunny day.