Classification and Application of Waterproof and Breathable Fabrics
Waterproof and breathable fabrics refer to textiles that, during wear, prevent liquid water from penetrating under a certain pressure, while allowing perspiration from the human body to pass through in the form of water vapor, keeping the wearer dry and comfortable. The waterproof and breathable property is achieved based on the principle that water molecules are much larger than water vapor molecules. The pores on the surface of the fabric are much smaller than water droplets but significantly larger than water vapor molecules. Garments made from such fabrics can resist wind, rain, and snow while remaining breathable, preventing overheating during exercise and maintaining comfort when movement stops. If a fabric were only waterproof but not breathable, sweat would accumulate inside, making the wearer feel cold. Moreover, these fabrics are also wind-resistant, maintaining a layer of still air between the body and the garment for warmth. Without windproof performance, insulation would be ineffective, leading to a cold sensation.
Types of Waterproof and Breathable Fabrics
Currently, there are three main types of waterproof and breathable fabrics:
High-Density Fabrics
These fabrics are made from high-count cotton yarns and superfine synthetic fibers woven into dense structures. They have high vapor permeability and moderate waterproof performance after water-repellent finishing. Their advantages include good breathability, softness, and drape, but they have low water resistance, a high defect rate, and difficulties in dyeing and finishing processes. Examples include superfine high-density fabrics and ultra-high-density cotton textiles.
Coated Fabrics
Coated fabrics are divided into hydrophilic and microporous types.
– Hydrophilic coatings form a continuous film on the fabric surface. Because the coating fills all pores, the fabric becomes waterproof. Hydrophilic polymer chains absorb moisture on the high-humidity side and release it on the low-humidity side through hydrogen bonding and molecular interaction.
– Microporous coatings contain fine pores that are small enough to block liquid water but large enough for water vapor molecules to pass through.
Although coated fabrics are easy to process, they have relatively low moisture permeability and hydrostatic pressure resistance.
Laminated Composite Fabrics
Laminated fabrics combine waterproofness, breathability, windproofness, and thermal insulation. They are made by laminating ordinary fabrics with expanded polytetrafluoroethylene (E-PTFE) membranes, complementing each material’s strengths. This technology represents the main development direction for waterproof and breathable materials today.
Currently, the latter two types—coated and laminated fabrics—are most widely used. Test data show that under normal temperature and static conditions, thermoplastic polyurethane (TPU) and PTFE offer comparable waterproof and breathable performance. However, under active or low-temperature conditions, TPU’s moisture transport capability decreases sharply due to molecular contraction, becoming almost zero below 0°C and brittle at -15°C. In contrast, E-PTFE maintains stable structure and moisture permeability from -150°C to -300°C.
Additionally, the micropores in E-PTFE form a complex network rather than straight channels, effectively blocking wind while allowing vapor transmission, thus providing both windproofing and thermal insulation. Therefore, E-PTFE is considered an ideal material for use in harsh environments.
High-Density Fabrics
These fabrics are made from high-count cotton yarns and superfine synthetic fibers woven into dense structures. They have high vapor permeability and moderate waterproof performance after water-repellent finishing. Their advantages include good breathability, softness, and drape, but they have low water resistance, a high defect rate, and difficulties in dyeing and finishing processes. Examples include superfine high-density fabrics and ultra-high-density cotton textiles.
Coated Fabrics
Coated fabrics are divided into hydrophilic and microporous types.
– Hydrophilic coatings form a continuous film on the fabric surface. Because the coating fills all pores, the fabric becomes waterproof. Hydrophilic polymer chains absorb moisture on the high-humidity side and release it on the low-humidity side through hydrogen bonding and molecular interaction.
– Microporous coatings contain fine pores that are small enough to block liquid water but large enough for water vapor molecules to pass through.
Although coated fabrics are easy to process, they have relatively low moisture permeability and hydrostatic pressure resistance.
Laminated Composite Fabrics
Laminated fabrics combine waterproofness, breathability, windproofness, and thermal insulation. They are made by laminating ordinary fabrics with expanded polytetrafluoroethylene (E-PTFE) membranes, complementing each material’s strengths. This technology represents the main development direction for waterproof and breathable materials today.
Currently, the latter two types—coated and laminated fabrics—are most widely used. Test data show that under normal temperature and static conditions, thermoplastic polyurethane (TPU) and PTFE offer comparable waterproof and breathable performance. However, under active or low-temperature conditions, TPU’s moisture transport capability decreases sharply due to molecular contraction, becoming almost zero below 0°C and brittle at -15°C. In contrast, E-PTFE maintains stable structure and moisture permeability from -150°C to -300°C.
Additionally, the micropores in E-PTFE form a complex network rather than straight channels, effectively blocking wind while allowing vapor transmission, thus providing both windproofing and thermal insulation. Therefore, E-PTFE is considered an ideal material for use in harsh environments.
Applications of Waterproof and Breathable Fabrics
Military Applications
Waterproof and breathable fabrics were first developed and applied in the production of military uniforms and protective clothing. For air force pilots, naval sailors, and special operations soldiers, sudden immersion in cold water can cause rapid loss of body heat—one of the main factors leading to injury or death. Waterproof and breathable garments have therefore been adopted by the U.S. Air Force, naval crews, and special forces units engaged in sea, land, and air missions as special protective uniforms. These garments can provide up to two hours of protection in cold water at 7°C, while remaining lightweight and comfortable. The introduction of waterproof and breathable fabrics not only resolves the contradiction between ventilation and water resistance but also significantly reduces the weight of rain gear, thereby lightening soldiers’ overall load.
Civilian Applications
In civilian use, waterproof and breathable fabrics are most commonly applied in outdoor products such as tents, sleeping bags, jackets, and footwear. For instance, outdoor sleeping bags require warmth, breathability, and light weight. Fabrics laminated with PTFE microporous membranes are often used, featuring a double-layer structure: an outer nylon fabric and an inner PTFE membrane. Such sleeping bags pose no risk of hypoxia or carbon monoxide poisoning during use.
Because PTFE material has excellent chemical resistance and flame retardancy, along with its microporous film structure providing superior waterproof and breathable performance, it has become an ideal material for developing nuclear, biological, and chemical (NBC) protective clothing.
Waterproof and breathable laminated fabrics not only meet the clothing needs of people engaging in activities under harsh weather conditions such as extreme cold, rain, snow, and strong winds, but also cater to everyday needs such as raincoats and footwear. This gives the material broad prospects for application and development.
In the future, research and development on waterproof and breathable fabrics will focus on cost reduction, as well as achieving lighter weight, greater comfort, and multifunctionality.
Waterproof and breathable fabrics are high value-added products with wide-ranging applications. Different production techniques yield products with distinct characteristics, though each still has room for improvement. This calls for continued innovation and effort from researchers and engineers to develop fabrics with enhanced comfort and functionality, in order to meet the growing demands of modern consumers.
Our company has machines for air permeability test for fabric and water vapor permeability tester. Interested readers can click on the link above to learn more.
Waterproof and breathable fabrics were first developed and applied in the production of military uniforms and protective clothing. For air force pilots, naval sailors, and special operations soldiers, sudden immersion in cold water can cause rapid loss of body heat—one of the main factors leading to injury or death. Waterproof and breathable garments have therefore been adopted by the U.S. Air Force, naval crews, and special forces units engaged in sea, land, and air missions as special protective uniforms. These garments can provide up to two hours of protection in cold water at 7°C, while remaining lightweight and comfortable. The introduction of waterproof and breathable fabrics not only resolves the contradiction between ventilation and water resistance but also significantly reduces the weight of rain gear, thereby lightening soldiers’ overall load.
Civilian Applications
In civilian use, waterproof and breathable fabrics are most commonly applied in outdoor products such as tents, sleeping bags, jackets, and footwear. For instance, outdoor sleeping bags require warmth, breathability, and light weight. Fabrics laminated with PTFE microporous membranes are often used, featuring a double-layer structure: an outer nylon fabric and an inner PTFE membrane. Such sleeping bags pose no risk of hypoxia or carbon monoxide poisoning during use.
Because PTFE material has excellent chemical resistance and flame retardancy, along with its microporous film structure providing superior waterproof and breathable performance, it has become an ideal material for developing nuclear, biological, and chemical (NBC) protective clothing.
Waterproof and breathable laminated fabrics not only meet the clothing needs of people engaging in activities under harsh weather conditions such as extreme cold, rain, snow, and strong winds, but also cater to everyday needs such as raincoats and footwear. This gives the material broad prospects for application and development.
In the future, research and development on waterproof and breathable fabrics will focus on cost reduction, as well as achieving lighter weight, greater comfort, and multifunctionality.
Waterproof and breathable fabrics are high value-added products with wide-ranging applications. Different production techniques yield products with distinct characteristics, though each still has room for improvement. This calls for continued innovation and effort from researchers and engineers to develop fabrics with enhanced comfort and functionality, in order to meet the growing demands of modern consumers.
Our company has machines for air permeability test for fabric and water vapor permeability tester. Interested readers can click on the link above to learn more.
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