Best way to get laundry detergent to dry on plastic cherries?

February 25, 2019 8:49 PM

Arts and crafts project: trying to figure out how to get liquid Tide to dry faster when painted on plastic cherries, or whether there’s some kind of clear coat that would make the whole thing dry (ish) to the touch.

My kid’s working on a school project where he’s trying to get plastic cherries to glow under an LED “blacklight” flashlight. (You don’t even want to know how the project has evolved to get to this point.) He settled on painting the cherries with liquid Tide, which is fantastic - clear under normal light, lights up bright blue-gray under the flashlight - EXCEPT the Tide is still wet 24 hours after being painted.

The cherries do not need to be handled excessively. They will be presented in a plastic bag, he just wants to make sure the Tide doesn’t rub off into a gooey mess on the inside of the plastic bag.

He’s tried: using a hairdryer, and some seche vite clear nail polish top coat, but no luck. Does he just need to be more patient, or does he need to find a different glowing medium, or could he paint the cherries with clear spray paint or something?

posted by faustessa to Grab Bag (14 answers total)

If it's humid, the soap will dry more slowly.

You might try laying the cherries on a cookie sheet or parchment paper and putting them in a gas range in the OFF setting so just the pilot light gently heats them. Same for a small watt incandescent bulb in and enclosed box.

The plastic substrate that is the cherries does not encourage the thick, viscous soap to dry===and it is also not formulated to dry since it's liquid soap.

Just a suggestion, but you may have better luck writing on a white tee shirt or some other absorbent cloth which will readily dry, or some other type of absorbent surface like untreated wood. The liquid soap should dry much faster, and will hopefully still fluoresce.

If you add any other opaque ingredients like sand it will destroy the fluorescent quality. Resins like nail polish or glues will trap the liquid and prevent drying.

Also, spiders fluoresce under uv light so there's that. They don't even need Tide.

I hope this is helpful.
posted by effluvia at 9:08 PM on February 25, 2019 [1 favorite]

I'd use highlighter pens and then a clearcoat.
posted by aubilenon at 9:14 PM on February 25, 2019 [2 favorites]

There are markers that fluoresce, and they are otherwise invisible. Here is one.
posted by Oyéah at 9:43 PM on February 25, 2019 [1 favorite]

Woolite dries much quicker than Tide for this purpose.
posted by fshgrl at 9:48 PM on February 25, 2019 [1 favorite]

maybe try mixing it with white glue? try less tide to more glue?
posted by The otter lady at 9:49 PM on February 25, 2019

What about sanding the surface of the plastic cherries a bit so they aren't as slick? Maybe that will give the Tide pen liquid more to grip?
posted by Hermione Granger at 10:13 PM on February 25, 2019 [1 favorite]

I would honestly just wash the Tide off and use something else. I've got detergent spills in my laundry that are still slimey months later.

B12 glows a nice bright yellow, and comes in nice dry pills that can be crushed and mixed with white glue, which will dry like white glue.

Here are some other household items that will glow like that.
posted by Jilder at 10:45 PM on February 25, 2019 [17 favorites]

Can the cherries be replaced by clear plastic balls so the Tide can be on the inside?
posted by Too-Ticky at 3:16 AM on February 26, 2019 [1 favorite]

Or can the cherries and the Tide be wrapped in plastic wrap and then sealed?

... Condoms? Maybe?
posted by Too-Ticky at 3:17 AM on February 26, 2019

The ingredients list for liquid Tide includes propylene glycol, which absorbs water from the air, and is probably included to prevent the mixture from drying.

Best quick substitute would be to make a solution of solid laundry detergent and paint the cherries with it; alternately you could use water in which a yellow or green highlighter had been soaked (though those pigments decompose in air slowly over time, would be more visible in normal light, and would produce a thinner solution which would be harder to paint with. Not sure if white glue would make these problems worse or not.). Vitamin B₂ (riboflavin) fluoresces yellow-green in UV but might have a smell; I can't remember which B vitamins smell like which things at the moment. I mention it because I think it's likely to be cheaper than B₁₂, though B₁₂ could work too.
posted by Spathe Cadet at 8:08 AM on February 26, 2019 [1 favorite]

Tonic water also fluoresces under UV - fill a baggy (or condom) with it? It'll be clear under full spectrum, but glow blue under UV.
posted by porpoise at 10:20 AM on February 26, 2019

Does the color matter? Because pink highlighter would be invisible over red. Wildfire paints has invisible clear UV colors, but boy howdy they are expensive (4oz blue: $28, red: $56)...but they REALLY work and are super-bright.
posted by sexyrobot at 10:41 AM on February 26, 2019

> I would honestly just wash the Tide off and use something else. I've got detergent spills in my laundry that are still slimey months later.

Seconding. Getting Tide to dry is a Sisyphean situation.
posted by desuetude at 11:18 PM on February 26, 2019

How about this nail polish top coat which is black light reactive?
posted by Constance Mirabella at 10:50 PM on March 2, 2019