Every industry has its own product names and many times those brand names become synonymous with the actual product.
Like Hoover, Sharpie, Tupperware and Velcro, Correx is another one of those trademarks that became the generic term.
Correx, or to give the product its Sunday name – fluted polypropylene – is a twinwall corrugated plastic. Its designed for strength and used primarily for printing on in the graphics and sign market.
That’s the reason we’re delving into it today for a once over about what it does, what’s good about it and why we use it for certain jobs.
Fluted polypropylene doesn’t exactly trip off the tongue when you’re ordering a pack of 8×4 sheets. You can see why in the UK, Correx has become the go-to name for describing the product.
Other brands of fluted polypropylene available are Twinplast, Corriflute, and in the USA, Coroplast. Coroplast has the same level of brand recognition in the US as Correx has over here.
Uses of Correx
Correx has always been used for estate agent boards. It’s waterproof, lightweight yet resilient so even though it bears the brunt of the traffic, wind and the weather outside homes for sale, it usually keeps up and stays in place. Another popular use is for all the election signage. Next time you’re driving along the road and being told to Vote For…., you can be fairly sure the candidate chose Correx to help get their party’s message across.
Temporary signs cable-tied to a lamp-post or railing? Probably drilled and printed Correx. Along with vinyl banner, it’s the Village Fete sign substrate of choice!
When you look at its profile, all the flutes are in line and like little girders. These flutes help with strength just like girders and also keep it cost effective compared to a solid sheet. I don’t see rigid polypropylene in much thicker gauges than 1200mic (1.2mm) so with Correx being usually around 4 to 6mm you can quickly see why it’s much more economical to produce with much less material needed to manufacture. It’s a trade-off between overall toughness and suitability against cost per sheet for its intended purpose.
For economical and short to medium term signage which needs to be on a rigid substrate instead of something like a vinyl banner, Correx is certainly up for the job.
Now, being polypropylene, the face of Correx has a low surface energy that in layman’s terms means it can be an issue getting stuff to stick to it. Originally screen printing the image was the way as those solvent inks would chew their way in. Once digital rollfed inkjet became more prevalent then printing onto self-adhesive vinyl and applying was the next option – there were issues though with different types of vinyl not adhering quite as well as necessary but for short-term applications, it usually worked. With UV curable inkjet its pretty much now back to the ink adhesion of screenprint but with the option of full-colour graphics to boot. Correx printed signs go upmarket!
Just as with Mr Sellotape, it must be great to own the trademark!
Most people specify or ask us for Correx even though as I said, it’s really a fluted or twinwall polypropylene.
The brand name of Correx is held by UK manufacturer DS Smith. Along with Correx, they create other similar products such as Akyprint or bubble board along with a solid polyprop sheet.
Like Correx, Akyprint is a twinwall product with a face and back sheet. The difference though is that instead of flutes running along the length or width of the board, dots or bubbles are in-between the two panels. These bubbles create a strong sheet that doesn’t have the lines that can be visible on the face of a standard fluted polypropylene.
At this point, I feel like passing the This Is Your Life red book over to Correx and watch the title credits roll.
As the theme tune starts, let’s give a quick recap:
It’s a cost-effective, waterproof rigid substrate that is still lightweight and durable. Available in a wide number of sizes maxing out usually at 1.5 x 3m along with flutes running parallel to either width or sheet length. Correx lends itself to economical short to mid-term outdoor signage and, useful when printing directly onto, its also available in a range of colours. Correx printing is simple enough when using screenprint or digital UV inks.
It can also have vinyl applied to it. Give it a quick test first though as not everything likes to stick to it.
So there you go, a brief 101 into Correx and how it fits in with modern print, signage and display.
For a new paper product that has a similar construction to Correx, check out this post on using and printing Dispa board.