Knowledge of Bags


What is PP Material ?

Polypropylene (PP), also known as polypropene, is a thermoplastic polymer used in a wide variety of applications including packaging and labeling, textiles (e.g., ropes, thermal underwear and carpets)

It is flexible and tough, especially when it is copolymerized with ethylene.

This copolymerization allows this plastic to be used as engineering plastic that is in a number of different products and uses. The flow rate is a measure of molecular weight and this determines how easily it will flow during processing. Some of the most significant properties of polypropylene are: Chemical Resistance: Diluted bases and acids don’t react readily with polypropylene, which makes it a good choice for containers of such liquids, such as cleaning agents, first-aid products, and more.

What does the GSM Stands for?

It stands for the thickness of the bag. Usually it is hard for us to use centimeters describing the thickness of the bag, but much easier for us to understand by the weight of the bag. And GSM which means the gram of the bag per square meter is known by us. The normal GSM that we use for the pp woven bag is from 42 gsm to 120 gsm. The digital is bigger, the thickness is bigger. You could choose the thickness based on your requirement. For example, the items’ volume is bigger and weight is not heavy, you could choose GSM not that big and the price is cheaper. But if you choose to load items with small volume but heavy weight, bigger GSM is needed.

Why Pp Woven Sacks have different durability and strength?

The durability and strength is all based on the tension of the pp woven bag. The tension could be described as pulling strength when you stretch it to its top. The tension unit is “N” , the bigger of the N, the stronger of the bag. So if you trust the N of the bag, we also could show you the test result.

What is offset printing and color printing?

The offset printing is the simplest ways to print your own logo, before we do the offset, we will make a mold of your logo then stick the mold on the color rolling bucket. The advantages of offset printing are that, easy to operate, cheap to make samples, disadvantages: colors could not be over 4 and the color is not bright as color printing.  But the color printing could be as many as you wish. It uses opp laminated to cover the surface of pp woven bag, so the colors could be much more flexible, the color effect is excellent. It is hard to do sample printing, and the mold fee is expensive than offset printing.

Why is the laminated pp woven bag waterproof?

If pp woven bag is laminated, which means the pp bag’s surface has a very thin opp plastic. The opp is waterproof. Of course, we could put a Pe liner bag in the pp bags, it is also could be waterproof.