Are waterproof backpacks really completely waterproof?

Not necessarily. Truly waterproof backpacks require sealed zippers, welded seams, and other features that prevent water from seeping in. Most bags are water-resistant, meaning they can handle splashes or brief exposure but aren't suitable for prolonged submersion. When buying, check the waterproof rating and design details to ensure the backpack meets your needs.

 

What technology should a backpack that is really close to absolute waterproof have

High frequency welded joints:

High-frequency welding joint technology includes HF (High Frequency) and RF (Radio Frequency), which are similar in principle, but different in specific application and technical details. Here are their detailed explanations:

 

(a)HF (High Frequency) welding

• Technical principle: HF welding uses high-frequency electromagnetic waves (usually 13.56MHz) to generate oscillations through the surface of the material, so that the internal friction of the molecule generates heat quickly, reaching the welding temperature, thus bonding the material together.
• Application materials: Mainly suitable for PVC, TPU and other thermoplastic materials, these materials can effectively fuse under high frequency oscillation.

 

Advantages:

• High strength joints: The strength of the welded joints is almost equal to the material itself, and the durability is excellent.
• Precise control: The area, shape and time of welding can be controlled, suitable for welding of complex shapes and designs.
• Fast and efficient: The entire welding process is fast and suitable for mass production.

 

(b) RF (Radio Frequency) RF welding

• Technical principle: The principle of RF welding is similar to HF welding, using RF energy (usually in the 27.12 MHz frequency range) to heat thermoplastic materials. Through the action of an electric field, the material molecules generate heat inside and melt, and finally bond together.
• Application materials: Also applicable to PVC, PU, EVA and other materials. Compared to HF welding, RF welding performs well on a wider range of thermoplastic materials.

 

Advantages:

• Wide applicability: RF welding is suitable for a wider range of material types and thicknesses, and has a wide range of applications.
• Strong seal: welded joint uniform, no gap, excellent waterproof performance.
• High precision: RF welding provides a high degree of accuracy and consistency when manufacturing precision products.

 

2. Waterproof zipper

(a)TIZIP waterproof zipper

How it works: The TIZIP zipper uses a special polyurethane coating and a highly sealed zigzag design that completely blocks water, air and dust. Its chain of teeth forms a completely sealed barrier when closed.

Application: Widely used in professional waterproof backpacks, diving bags, dry bags, etc.

Advantages:

• Extremely waterproof performance: It can also maintain a seal under extreme water pressure, and is currently recognized as one of the strongest waterproof zippers.
• Durability: TIZIP zipper has high tensile strength and is not easy to deform, which is suitable for high frequency use environment.

 

(b) YKK AquaSeal waterproof zipper

Technical principle: The YKK AquaSeal zipper uses a thermoplastic polyurethane (TPU) outer coating, combined with an innovative waterproof seal tooth design, making the zipper completely waterproof when closed.

Application: Often used in outdoor adventure backpacks, sailing equipment, extreme sports bags and other products requiring high waterproof requirements.

Advantages:

• Lightweight and waterproof: Compared to traditional waterproof zippers, AquaSeal weighs less, but also provides excellent water resistance.
• Fluency: The zipper slides smoothly, reducing the sense of friction in use and convenient operation.

 

(c)YKK AquaGuard waterproof zipper

How it works: The AquaGuard zipper has a waterproof polyurethane coating, which is not completely waterproof, but is well resistant to splashing and short soaking.

Application: It is mostly used for hiking bags, riding bags and other backpacks that need a certain anti-splashing ability.

Advantages:

• Cost-effective: Compared to fully waterproof zippers, AquaGuard is more economical and waterproof enough for everyday outdoor use.
• Tear resistance: The zipper structure is strong and suitable for a variety of high-strength use scenarios.

 

(d)Riri waterproof zipper

Technical principle: The Riri waterproof zipper is designed with a rubber coating and precision zipper to ensure complete sealing, and the zipper prevents water, dust and air from penetrating when closed.

Application: Riri zippers are commonly used in luxury waterproof bags and professional diving equipment.

Advantages:

• High quality material: The zipper is durable, smooth and corrosion-resistant for saltwater and extreme environments.
• Strong seal: It can maintain perfect sealing effect even under extremely high water pressure.

 

3.Waterproof materials

TPU (thermoplastic polyurethane) coated fabric: TPU is a soft and highly elastic material that forms a strong waterproof barrier by coating TPU on nylon or polyester fabrics. This material not only resists high water pressure, but also has excellent tear and wear resistance, is lightweight, easy to fold and store, and is widely used in professional-grade waterproof backpacks and dry bags.

 

PVC (polyvinyl chloride) coated fabrics: PVC coated fabrics cover fibrous fabrics with a layer of PVC, providing excellent water resistance and complete resistance to water penetration. This material is durable, tear resistant, stable in harsh environments, is a common material for highly waterproof equipment, such as drift bags and waterproof bags, and has a high cost performance.

 

Nylon 66 with high Density coating: Nylon 66 is a durable engineering plastic that combines with a high density waterproof coating to create multiple protections against water, tear and wear. This material not only provides excellent strength, but also resists the impact of strong currents, making it suitable for a variety of outdoor environments and a common choice for hiking and travel bags.

 

Hypalon (chloro-sulfonated polyethylene) : Hypalon is a highly weather-resistant synthetic rubber that is widely used in waterproof equipment in extreme environments. It is resistant to ultraviolet light, chemical corrosion and extreme temperatures, the material does not absorb water and can maintain long-term waterproof effect, suitable for waterproof bags, drift bags and life-saving equipment requiring extremely high durability.

 

Cordura fabric and waterproof coating: Cordura is a high-strength nylon material that, when combined with a waterproof coating, provides excellent wear resistance and medium to high grade water resistance. Lightweight and strong, the material can be adjusted to suit different levels of waterproofing, making it ideal for outdoor adventures, hiking and riding.