You probably think of them as “Ziploc” bags, but, technically, the generic term is zipper bag. Everything from electronic components to coffee beans arrive in them. But they weren’t always everywhere, and it took a while for them to find their niche.
A Dane named Borge Madsen was actually trying to create a new kind of zipper for clothes in the 1950s and had several patents on the technology. The Madsen zipper consisted of two interlocking pieces of plastic and a tab to press them together. Unfortunately, the didn’t work very well for clothing.
A Romanian immigrant named Max Ausnit bought the rights to the patent and formed Flexigrip Inc. He used the zippers on flat vinyl pencil cases and similar items. However, these still had the little plastic tab that operated like a zipper pull. While you occasionally see these in certain applications, they aren’t what you think of when you think of zipper bags.
Zipping
Ausnit’s son, Steven, figured out how to remove the tab. That made the bags more robust, a little handier to use, and it also rendered them less expensive to produce. Even so, cost was a barrier because the way they were made was to heat seal the zipper portion to the bags.
That changed in the 1960s when the Ausnits learned of a Japanese company, Seisan Nippon Sha, that had a process to integrate the bags and zippers in one step which slashed the production cost in half. Flexigrip acquired the rights in the United States and created a new company, Minigrip, to promote this type of bag.
Enter Dow
In 1964, Dow Chemical wanted to acquire the rights to the Minigrip bags to sell in supermarkets using Down’s polyethylene bags. And with this marriage, the Ziploc bag as we know it was born.
Dow continued driving down the cost, tasking R. Douglas Behr to improve how the Ziploc production line worked. Eventually, the bags were flying off the line at 150 feet per minute.
You can find plenty of videos of machines that “make” zipper bags on YouTube (like the one below). Many of them are surprisingly light on detail, and it isn’t clear now how many of them are molding zippers and how many are sealing premade zippers to bags or using rolls of bags with zippers in them already. However, the video below shows making “zip lines” from pellets and then creating bags from film. This creates giant rolls of zipper bag stock which are then cut into individual bags.
Slow Start
At first, consumers weren’t sure what to do with the zipper bags. Supposedly, a record company was set to put records in the bags but when an executive handed one to his assistant, the assistant ripped the bag open without using the zipper.
Regardless, consumers finally figured it out. Now, the zipper bag is a staple in electronics, food storage, and many other areas, too.
More Than Meets the Eye
Even the most ordinary things have details you don’t think about, but someone does. For example, zip bags can have one, two, or three zippers. Some have color indicators that show the seal. Some have strips that conceal the zipper so you can tell if the bag was opened.
There are special zippers for liquids and different ones that resist getting powder stuck in the seal. Some zip bags still have pulls, and some of those pulls are child-proof, requiring the user to pinch the tab to slide it. You can even get zipper bags that don’t use locking zippers but hook-and-loop closures.
Even though zipper bags don’t seem very glamorous, you can learn a lot from the Ausnits. Improve your product in ways that make people want to use it. Also, improve your product in ways that lower costs. We’d guess that when Ausnit bought the zipper patents, he’d never imagine how the market would grow.
You can see a talk from Steve Ausnit at Marquette University in the video below. If you’ve ever had the urge to be an entrepreneur, you can learn a lot from his talk.
The zipper-top bag revolutionized the packaging of…herbal mixtures…which up thru the 70s were still sold in plain plastic bags that were ineffectively spit-sealed. Or so I’ve been told… ;-)
Now it’s hard plastic tubes and tough MRE grade bags (locking seal inside) which are child proof because it’s legal and responsibly sold.
Good for packaging shareware.
I second life the ones I have for storing USB cables and earbuds.
Keeps the cables from inter-tangling.
And yes, I do have a lot of USB cables and earbuds!
More than just cables. Keeps messes more manageable.
From the explosion of zipper bags everywhere (especially in retail product packaging), one might guess that key patent(s) have expired. Does anyone know the IP status and/or timeline?
same question
“You probably think of them as “Ziploc” bags, but, technically, the generic term is zipper bag. ”
Ironically, “zipper” itself was once a trademark. Within a decade zippers had became so popular and ubiquitous–and the name “zipper” so firmly-linked to the device no matter who made/sold them–that the trademark was no longer defensible.
If you use the term “Ziploc bag,” everyone knows what you are talking about. Ask 100 people who owns that trademark, and I’d be surprised if even one could tell you. “Ziploc” is already well on its way to becoming “the generic term,” even if to the chagrin of SC Johnson’s lawyers.
Velcro Vice-president to Dow Vice-president:
“I think your people should talk to my people about defending your Trademark. They might even come up with a Song and Dance routine video that could go viral!”
The inventor’s name is not “Borge” but Børge. It was changed in the patent for the international market because outside Denmark and before unicode, the “ø” character could give some difficulties :)
My name is יהונתן ᛗᚫᚣᚩ
but people find it convenient if I use the English set of the modern Latin alphabet (so J instead of Cg).
I’m not sure how important ø versus o is to Danes, Norwegians, etc. But I’m pretty flexible with how people spell or pronounce my name.
It’s an entirely different letter of the alphabet. “Borge” in danish means “to guarantee”, while “Børge” is just a name.
“Unfortunately, the didn’t work very well for clothing.”
Missing a y somewhere…
“Unfortunately, the didn’t worky very well for clothing.”
FTFY!
B^)
I found that the zipper portion of these zipper bags had just the right stiffness to serve as the curtain around the base of a small air cushion vehicle made from salvaged mini RC plane motors. Serendipitous!
Do you have a picture to such a contraption? I cannot fathom how it looks. Thanks
The technology either needs improvement or the running out of business of inferior manufacturers. I’ve dealt with far too many bags that are very hard to reseal, and other bags that the zipper strip becomes separated from the bag.
Is there a de-facto standard for dimensions and shape of the joint and receptacle ?
Is it really airtight at the extremities of a ribbon ?
My mom did market research for various products in the late ’60s and these ‘zip lock’ bags were being tested as a leftover storage and reheating bags…as long as they didn’t burst open in the hot water.