Many brands of waterproof bags use waterproof tarpaulin. So what is waterproof tarpaulin?
Some webbed bags and waterproof backpacks are made of materials called waterproof oilcloth, which is actually a chemical fiber bonded PVC material, or PVC mesh or PVC bonded fabric.
Why not just call it PVC lamination or PVC mesh clip? Calling PVC directly by a name can make people feel like a low-end material, after all, the European Union has strict restrictions on the application of PVC, which belongs to non environmentally friendly materials and causes significant pollution to the Earth and nature.
Physical and chemical properties of waterproof oilcloth
The cost of PVC material is low, not to mention it is not environmentally friendly, and its physical and chemical properties are not very friendly. It has a strange smell, a strong taste, a poor feel, and is sticky. Low melting point, prone to melting and deformation in hot weather, and prone to cracking and fracture in cold weather. Even if the temperature difference range is very small (usually 0-40 degrees Celsius), it is easy to encounter problems when used in polar environments.
As a comparison, TPU materials are far superior, such as high melting point, high cold resistance, and a wide range of temperature differences suitable for use. Can be used in environments ranging from minus 25 degrees Celsius to high humidity of over 60 degrees Celsius. TPU is still an environmentally friendly material, and some food grade ones can even be used as drinking utensils. The EU's requirement for drinking water appliances is that PVC is generally prohibited, but TPU is not included in the prohibition.
Waterproof oilcloth is mainly divided into two types of PE/PVC laminations
The cost is relatively low. However, its physical and chemical properties can become brittle at low temperatures and melt at high temperatures (up to 70 degrees Celsius) in usage scenarios. Long term exposure to sunlight or wind and rain outdoors can quickly degrade and decay.
If the fabric of most waterproof bags is labeled as waterproof oilcloth, then it is likely to use PVC waterproof oilcloth. Both PVC/PE waterproof tarpaulins are relatively thick because their seamless fusion is a pseudo fusion, unlike TPU materials where molecules move and completely fuse between the two fabrics, making it difficult to peel off.
This makes it easier for us to distinguish what the material of the waterproof bag is. All waterproof tarpaulins have a relatively thick film, and because the fusion is not strong, we can only rely on stacking materials to increase the physical space for embedding and improve the fixation strength.
So, generally speaking, waterproof oilcloth bags on the market are heavier and more sticky, with a noticeable plastic feel; The waterproof bag made of TPU material is lighter, more comfortable to handle, odorless, and more approachable to people.
Harmony Bags has been engaged in bag manufacturing for 20 years. We are a professional company in producing various kinds of bags,such as cosmetic & toiletry bags, backpacks, travel bags, waterproof bags and waist bags. Our monthly production capacity is 500,000 bags. We can guarantee reliable quality, on-time delivery and good service.