Waterproofing
Waterproofing is essential in outdoor gear, clothing, and other products exposed to the elements. To make informed decisions about the right level of protection for your needs, it's important to understand the different grades of waterproofing and the technologies behind them.
Grades of Waterproofing
Water-Resistant:
Protection Level: Lowest.
Description: Water-resistant fabrics provide minimal protection. These fabrics aren't treated with waterproofing substances and can only keep you dry in misty conditions or very light rain. However, the dry time is limited, and they won’t stand up to heavier precipitation.
Water-Repellent:
Protection Level: Medium.
Description: Water-repellent fabrics offer better protection than water-resistant ones. They are typically treated with a substance that causes water to bead up on the surface, delaying absorption. While this treatment extends the dry time and can protect you during moderate rain, prolonged exposure will eventually allow water to soak through.
Waterproof:
Protection Level: Highest.
Description: Waterproof fabrics are designed to be completely impermeable to water. The pores of the fabric are fully sealed, often making them air-tight as well. These fabrics can withstand water pressure and are ideal for heavy rain and extreme conditions.
History of Waterproofing
Waterproofing methods have evolved significantly, influenced by geography, available materials, and technological advancements.
Traditional Techniques:
Tight Weaving: Historically, strong cotton with tight weaves was used, such as sailors' canvas and later, gabardine fabric invented by Thomas Burberry.
Natural Oils: Sheep wool, left unwashed to retain lanolin (a natural water-repellent oil), was another method used to prevent water penetration.
Natural Coatings: Indigenous techniques included pasting natural rubber or latex into fabric, coating with beeswax, or using tar, linseed oil, and paint to create waterproof garments like oilskins and the Mackintosh coat.
20th Century Advancements:
With the advent of synthetic chemicals, waterproofing technology took a leap forward. Polymers like fluorocarbons, synthetic waxes, and petroleum-based silicones became standard. However, some of these, particularly fluorinated chemicals (PFAS, PFOA, PFOS), were later found to be harmful to the environment and human health, leading to regulatory changes and a push towards safer alternatives.
What to Look for in Waterproofing
When choosing waterproof garments, here are some key points to consider:
Chemical Safety: Avoid materials treated with harmful chemicals like PFAS. Look for labels indicating FCF, PFAS-free, or fluorocarbon-free treatments.
Natural Options: Consider garments treated with natural waterproofing agents like beeswax, lanolin, or natural rubber. However, be aware that these are not always the most eco-friendly or vegan options.
Certification: For synthetic options, look for certifications like the Bluesign system, which ensures safe chemical use and environmental responsibility throughout the supply chain.
Latest Trends in Waterproofing
Innovations in waterproofing are focusing on environmentally friendly alternatives that offer effective protection without the negative environmental impact of older methods. Some of the latest trends include:
Silicon Dioxide Nanoparticles: These nanoparticles form tiny air pockets within textile fibers, creating a water-repellent surface. They also provide additional benefits like anti-bacterial and anti-wrinkle properties. Silica, the base material, is a natural compound derived from silicon and oxygen, making it an eco-friendly option.
Dendrimers: These are nano-scaled artificial macromolecules with water-repellent, anti-microbial, and self-cleaning properties. Dendrimers create a “lotus effect” on surfaces, which minimizes water adhesion and improves the fabric's ability to repel moisture.
Synthetic Waxes: While petroleum jelly or paraffin waxes are derived from petroleum, they are biodegradable and, if refined properly, are not harmful to humans. These waxes provide effective waterproofing and are an option to consider when looking for synthetic, yet environmentally safer, alternatives.
Understanding these different aspects of waterproofing will help you choose the right materials for your needs, ensuring that you stay dry while also being mindful of environmental impacts.