When it comes to selecting the right material for manufacturing waterproof bags, there are a variety of options to consider. As an established manufacturer, we HoneyDryBag concluded some common materials used for waterproof bags, with their advantages and disadvantages, plus the benefits and history of human using each material.
PVC
Polyvinyl chloride (PVC) is a durable and strong material that is resistant to water, punctures, and abrasions. It also provides protection against UV rays and chemicals, and it’s relatively inexpensive when compared to other materials. PVC can be easily manipulated into different shapes and sizes, which makes it ideal for customized waterproof bags.
PVC was first invented in 1872 by German chemist Eugen Baumann, and was commercialized in the 1940s. It is most commonly used as a coating material to the base fabric, then the product is assembled using high-frequency welding or heat-sealing techniques. High-frequency welding creates a strong and waterproof seal, eliminating the need for stitching, which can create holes that could potentially leak water.
The durability and resistance of PVC to water and abrasions make it a popular choice for waterproof bags. It’s also easy to clean and maintain, making it practical for outdoor activities.
However, PVC has various cons. Being made from petroleum, it is non-biodegradable and may have negative environmental impacts. When PVC is incinerated, it releases dioxin, a toxic substance that can cause cancer and other health problems. According to our material supplier, the production of PVC may require phthalates, a plasticizer that can interfere with hormone levels and cause developmental problems. That’s why we are reducing the use of PVC and replace it with more environmentally friendly options.
TPU
Thermoplastic polyurethane (TPU) is a versatile material with excellent tensile strength and abrasion resistance, along with good transparency and elasticity. Unlike PVC, TPU is a sustainable material as it can be recycled. TPU is also resistant to oils, greases, and chemicals.
TPU was introduced as a synthetic material in the 1930s. It gained popularity in the 1990s due to its excellent waterproof and durability properties. Since then, it has been used extensively to produce waterproof bags, backpacks, and other outdoor gear. TPU can be applied as a coating material to base fabrics to enhance the waterproof and durability properties of the final product.
TPU has two subdivisions, polyether TPU and polyester TPU. with slightly different properties. The excellent waterproofing property, lightness in weight, and flexibility make TPU an ideal material for producing waterproof bags.
However, the cons of TPU are also significant. Not only is it susceptible to degradation due to prolonged exposure to UV radiation, but also it is not completely resistant to high temperatures. The price of TPU is also a disadvantage as it is higher than PVC, which, in rare occasions, can be unaffordable. In early 2023, we tried yet failed to produce a TPU rain barrel: the water eventually leaks in the test due to the thickness of the material, and trying to use thicker ones would result in the great increase of cost.
Polyester
Polyester is a synthetic fabric that is commonly used in waterproof bags as the base fabric. It is naturally water-resistant, durable and resistant to wrinkles, shrinking, and fading. Unlike natural fabrics, polyester is resistant to the growth of mildew or mold, which can be a problem in damp or humid conditions. The fabric is also lightweight and can be machine-washed without issues.
Polyester was developed in the early 1940s as a substitute for silk, and became increasingly popular later as a versatile and affordable fabric for a wide range of consumer products. To produce waterproof bags from polyester, material factories typically start by weaving or knitting the fabric, then coat it with PVC or TPU for the waterproof properties. Polyester fabric coated with PVC or TPU is called “Tarpaulin”, and is one of the most common materials of waterproof bag.
However, polyester has disadvantages too. It is not as breathable as natural materials as it does not allow for much air flow. That’s why we included padded back design in our waterproof backpacks. Polyester can also sometimes generate static electricity on the waterproof bags. Furthermore, the production of polyester can generate greenhouse gases, making this material not as environmentally friendly as other materials can be.
Nylon
Nylon is a strong and durable fabric, resistant to scratches, tears, and abrasions. It has a high tensile strength, making it an excellent choice for bags and backpacks that need to carry heavy loads. Nylon is also water-resistant and quick-drying, making it a popular choice for waterproof bags, especially waterproof backpacks, duffel bags, and swim buoys, a floating bag for open water swimmers that can be designed to function as dry bags as well.
The history of nylon dates back to 1930s as a substitute for silk by DuPont. It was first used to produce parachutes and tires before becoming a popular material for bags. To produce waterproof bags from nylon, the material has to be coated with a waterproofing material first. This coating, which can be PVC, PU, silicone, etc., gives nylon greater resistance to water penetration.
Nylon is generally stronger and more abrasion-resistant than polyester, and generally more durable and tear-resistant than the new RPET. A blend of nylon and polyester is called Ripstop, which is a lightweight material with a grid-like pattern that prevents tears from spreading.
Through, nylon is not omnipotent. Nylon itself is only water-resistant, it can soak through in heavy rain or prolonged exposure to water. and thus, coating materials are a necessity to make it truly waterproof. Additionally, while nylon is considered an environmentally friendly material, it is made from petrochemicals and thus can take a long time to decompose.
RPET
RPET (Recycled polyethylene terephthalate) is an eco-friendly material made from recycled plastic bottles. When used in waterproof bags, RPET makes the product much durable, lightweight, and resistant to water and heat. RPET is famous as an eco-friendly alternative to other materials that can provide satisfactory waterproofing qualities. It is best suitable for those companies and consumers who want to support initiatives which help to reduce plastic waste and carbon footprint.
The development and use of RPET started in the 1990s, as a result of the increasing consumer concern over polluting plastics. The recycled PET was first used in the fashion industry and has since become popular for various applications. We at HoneyDryBag began producing waterproof bags and several other products using RPET in our factory since 2021 and has since supplied several commercial brands in the outdoor industry.
To manufacture a waterproof bag from RPET, the material is collected and cleaned, and then the plastic bottles are melted down to create fiber and yarn. The fibers are then cut and woven into a textile that is coated. Finally, the textile can be cut and assembled using welding machines to make a finished waterproof bag.
The disadvantage of RPET lies in the cost. It is significantly higher than the other materials, which is a key factor for business decision makers when sourcing waterproof bags. Also, RPET can be sometimes less durable than materials like PVC or TPU. Still, RPET is a great contender in the outdoor industry.
Conclusion
In conclusion, when it comes to choosing the right material for waterproof bags, there are several options to consider. PVC is a popular choice as a coating material for its durability and affordability, while TPU is sought after for its environmental sustainability and strength. As for base materials, Polyester and nylon are commonly used due to the durability and water-resistance. RPET is a newer addition to the market. It is eco-friendly and may be relatively expensive.
Each of the materials discussed has their pros and cons, making it essential for businesses to understand their unique needs while deciding which material is the better choice for their products.
At HoneyDryBag, we take pride in our sustainable and eco-friendly manufacturing processes that are designed to make waterproof bags that are durable, functional, and stylish. Contact us today and see how we can help your business.
