Two questions that keep coming up are: just what is PP? And what’s the difference between woven and non-woven PP?
There’s a third question which necessarily follows: Which is best for me?
It’s such a common question, it made me wonder if there wasn’t a straightforward answer already out there, and I couldn’t find one either.
So, the aim of this blog is to answer these questions, in simple terms, and help you find the bag you need.
Let’s start at the beginning. PP – what is it?
PP – or polypropylene – is a thermoplastic. In Layman’s terms, that’s a plastic which comes in many forms from resins to pellets and which, when heated and set, takes on the properties of a solid plastic, hardening as it cools. Best of all, this process can be repeated again and again, making it recyclable and re-usable.
PP is one of the most versatile plastics known to man, and can be found in everything from carpets and cars, to plates and planes. It can take many forms, from completely solid – like a garden chair, to fibrous, like the back of carpets – or bags.
PP has some great properties that make it especially good for promotional products. Firstly, it doesn’t absorb water (unlike nylon or polyester which makes it really good for the likes of school bags, shopping bags, cooler bags or beach bags, where water resistance is an important feature.
It’s also a brilliant insulator – which is why you’ll find products like flasks and cool bags made out of PP. Its characteristics allow temperatures to remain constant for longer – keeping cold things cold and hot things hot.
PP is also very cost effective. In terms of bags, it comes in two forms, and though there is a price difference between them, both are affordable when compared with other materials including polyester.
So and Woven and Non-woven. What’s the difference?
The names are self-explanatory. One is made from woven PP fibres, and the other isn’t.
More specifically, woven PP is composed of fibers woven together in sheets, aligned at 90 degrees to each other, with the fibers going over and under one another, as shown in the image above. Non-woven is made in special heated presses under pressure, to create a sealed sheet. Both materials are strong but woven PP is the strongest.
The videos below show how sheets of non-woven PP and how woven sheets are made.
The time involved to make a woven bag makes them more expensive than non-woven, but and both are very cost-effective when compared to rival materials.
Non-woven is better at keeping the water out, as it is a solid sheet of material, whereas woven bags can let water through the weave. An alternative here is a laminated woven bag, which will add the level of protection required, while retaining the positive features of woven PP; this is always something to check when ordering a woven bag as to whether it is laminated or not.
For promotional materials, both materials lend themselves towards shopping bags – with the woven type being more suited for big loads, such as bottle bags or even sand and building materials. Below are some prime examples of woven and non-woven PP bags.
In general, however, non-woven PP tends to have more uses in the promotional market.
It can be manufactured much more efficiently, and cost effectively, increasing its appeal as a material.
And Now in Colour
For example, from stock (i.e. off the shelf) you can find all of the following made from non-woven PP: beach bags, cooler bags, dress/suit bags, messenger bags, aprons, rucksacks & backpacks and even car windscreen shades. Also, the manufacturing methods allow easy dying of the material, therefore not only do you find a large product range, but an extensive colour range too – take a look at this non-woven shopper bag and the standard colours it is available in.
With woven bags, off-the-shelf choice is limited – in many cases a woven bag would be custom-made, so it’s worth bearing in mind the extended lead times; from scratch, delivery time could take anything from 6-12 weeks after approval of artwork. To find out more about custom bags, have a look at our Bespoke Bag Page.
One feature of both woven and non-woven bags is that the surface has texture. From an aesthetic viewpoint it gives the bags a unique look, which looks especially nice with the bright colours, however, for some there is an issue with print clarity. If your artwork is intricate with a lot of detail, it’s worth checking with en expert to see if the print will work. If it’s too detailed you may want to opt for a bag with a smooth finish, like light cotton, or polyester. But it is still possible to get a great finish with a detailed picture, so don’t write off PP just yet:
At Bags of Ideas we believe PP bags are a great option, with an attractive price point, durability and great versatility. Even the printing limitations are actually not that limiting. But don’t take our word for it – try a PP bag yourself!