In this case, someone says: "I think that has something to do with static electricity... The pattern is partly determined by the flowing plastic when it was on its journey through the injection-moulding process." And somebody else shows up with the perfect background to explain:
Yep. I work in food manufacturing, and one of the product we make is individual drink mix sticks (packets). One particular product was difficult to run because powder kept contaminating the seal. Eventually we discovered that the powder was sticking to the film in a particular pattern, before the film had even gone through the machine. There was static embedded in the film right from the film factory (or, at least certain patterns on the film laminate were a different surface finish which concentrated the static charge generated when the film was unrolled). We aimed an ionization bar at the film before the powder injection station of the machine: problem solved.I love seeing the internet perform so well.
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16 comments:
Your television is an ionization bar.
I'm not interested in an internet without jokes.
Try shaking certain plastic DVD coverings from your fingers. They always stick to another finger. Pulling them off the DVD case charges them up.
What's interesting here is not static electricity per se but the distinctive *patterns* the sugar made on the spoon.
Very interesting sub-reddit. Thanks for pointing it out.
"I love seeing the internet perform so well."
It couldn't just be white men, could it?
That would be racist.
but the distinctive *patterns* the sugar made on the spoon
These *patterns* are made BY DEMONS!
You are FOOLS for mentioning them; You Are Now CURSED!
This comes from improper thought and actions
REPENT! THE END IS NEAR!!!
Static electricity is an interesting thing many manufacturers have to deal with. My old employer Richmond Technology was a pioneer in anti-static plastic, solving a problem for NASA in the late ‘80s after a rocket squib exploded by being set off when a plastic tarp created a spark. This led to a whole industry of shielding, ionizing, and various packaging materials designed to prevent even tiny voltage charges from ruining printed circuits and components. Some components were so sensitive even less than 10 volts would damage a chip, which eventually led to all the workers being grounded with a wire on their wrist and every handtool had to be made with anti static grips or materials that would conduct through the operator to ground. Any small metal object can be a low-voltage capacitor, and you don’t feel a static charge leaving your finger until it gets to 5000 volts. When you see a spark from your finger that’s in excess of 10,000 volts. So as electronic architecture shrank we chased smaller and smaller sources of static discharge, tweezers and spudgers and even clean room gowns had copper sewn in to take body-generated static to ground. Fun fact: I was using a static field meter to test how much voltage my big cat Butch could generate if I rubbed a balloon on him and the meter peaked at just over 50,000 volts. Then he whipped his tail and touched my CRT and zapped my computer off. Discharged! Even a cat can be a capacitor!
Ah just recalled ESD is the name of the phenomena, electro-static discharge. I am fascinated by the static per se, for the pattern it has left in my life and career. It’s effects are everywhere and touch many industries and occupations.
Crowdsourcing is one of the phenomena for which the internet is useful. Not sure all the crap storms we experience from it enabling social media and anonymous rage makes it worth it though.
Thanks Ann for an interesting diversion on an interesting blog.
Static electricity is always an interesting phenomenon. Also a big problem in packaging,especially with films. One person in the reddit comments mentioned getting a big jolt from a roll of film and being hospitalized overnight.
Here's another case I once wrote about.
https://www.packagingdigest.com/coding/case-sparky-conveyor
The spoons are made by squeezing plastic pellets, with a bit of added heat until the blend together into a not quite liquid but not quite solid mass. This is then forced (injected) into a spoon shaped mold at great pressure.
The plastic going into the mold is fairly uniform but not completely. Variations in the density of the plastic will cause variations in the static charge. Variations in charge mean variations in static cling thus variations in the pattern.
John Henry
The first anti-static plastic was “pink poly” made by combining dish soap with polyethylene in a blow line. It works because the surfactant is hydrophilic and a thin layer of moisture forms that dissipates static instead of letting it “hide” in the poly by clinging to ions on the other side of the thin moisture barrier. It worked. Solved NASA’s problem and prevented additional deaths. The original ESD event with the squib had killed a NASA scientist. I’m unaware of any interesting patterns caused by that static discharge.
The response on plastic film thatyou cited was interesting and a constant problem in flexible or film packaging. Especially since there are often fine particles that want to stick.
While the film is extruded from pellets as in the spoon molding, it is not put into a mold. It is either squeezed between 2 rollers into a sheet or blown in tubular form.
There will still be static. Now I wonder if, due to the process and the thinness of the film it would form patterns or be more uniform.
Not that it would make muc difference on the packaging machine. Patterned or uniform, any powder in the seal I s going to cause a leak.
John Henry
Even with the admonition there are jokes on that sub-reddit - erudite rather than juvenile
Cool article. Thanks. I like this flavor of free ice cream
Believe a confident answer to an obscure question at your risk. Some of the posts in that thread start out with one or more very certain responses, voted to the top of the comment heap, which are completely wrong. Down lower in the threads are frustrated respondees who have to pile on references, links, citations and deep scientific analyses to prove who is correct.
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