Re: Sweat and food stains vanish under blue light

The practice of 'airing' washing on the line in sunlight has many benefits (if your garden isn't on the flight path of incontinent birds).

That is just about the oldest way in the world of bleaching natural fibres - hang it out in direct sunlight for as long as it takes!

I'm not convinced about "without harming delicate fabrics though". I suspect it does some damage to the surface layers of the fibres too.

Absorbing blue light is really tough on the molecules that do it. They tend to suffer a certain amount of damage with sufficient exposure and the breakdown products are either soluble or not coloured (often both).

Shine pure blue light on your printer output and you will be able to see the unique defect forensic pattern of yellow single pixels it prints.

Near-UV flashlights are fun.

All AI-created images should be required to have embedded ID.

My whiteboard gets some daylight, and that poymerizes certain colors after a day or two and makes them hard to erase.

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I clean that with what we call here "cleaning alcohol". Isopropyl alcohol or ethyl alcohol (ethanol) with a high concentration of water (usually 70%).

I cleaned it with actone and it got horrible, all smeary and hard to erase. Marnex cleaner/conditioner fixed it up great. It must need some mysterious coating or something.

What is the make and model of the whiteboard? It is probably MDF coated with some kind of white paint or lacquer that dissolves in acetone. Try 190-proof Everclear ethyl alcohol instead (normally used for preparing extractions of essential oils). Isopropyl is not as good a solvent.

What really works is a porcelain-enamel steel dry-erase whiteboard. Totally solvent-proof. We have one in the kitchen, and it is heavily used. I was just cleaning some recalcitrant marker shadows off that board with straight acetone.

If one is having problems with smearing versus cleaning, use a ~ 50-50 mixture of acetone and ethyl alcohol. The acetone dissolves the shadow, but quickly evaporates, leaving the shadow as dust in the alcohol, which does not re-deposit and so can be wiped away.

Joe

Acetone is way too good a solvent for plastics.

Methylated spirits or IPA (the alcohol not the beer) are OK solvents for white board use if the ink has dried and polymerised.

My current printer couldn't produce a clear pattern of yellow pixels if you hit it with 50,000 volts - never mind copying a banknote with any kind of expertise.

Mind you, back in the day, the first HP inkjets could make a fair run at french colonial specie.

I think they've been bolloxed intentionally.

RL

It's painted steel, and the paint is not oven cured (unlike for instance automobile paints), so it's no surprise that acetone will strip it.

Your whiteboard is the same size and likely weight as my kitchen whiteboard described below. I think mine is a Quartet, with wooden frame and tray.

Joe

Our main whiteboard is thin float glass with a steel sheet backing, with a faint 2-inch grid.

It’s easy to erase, survives any solvent short of HF, and holds rare earth magnets, albeit weakly.

Cheers

Phil Hobbs

Magnets stick to mine pretty hard. I can stick drawings up there, which is handy in brainstorming sessions.

We have a big OLED screen right next to the whiteboard for multimedia events. I just had another goofy product idea so when the sleepy teenagers finally stagger in, we can play with that. It really helps to get a few guys - experienced and not - together and talk.

Whiteboards are catalysts.

That sounds impervious for sure. Porcelain-enamel steel is equally impervious (the enamel being vitrified glass), but the glass layer is far thinner, so magnets do stick quite well. Same as for painted steel.

A wood frame (oak in my case) is far easier to securely mount to the wall. This option may no longer be available, but weighs about 30 pounds.

Joe