Durable water repellent

Last updated
Fluorine-containing durable water repellent makes a fabric water-resistant. A water droplet DWR-coated surface2 edit1.jpg
Fluorine-containing durable water repellent makes a fabric water-resistant.

Durable water repellent, or DWR, is a coating added to fabrics at the factory to make them water-resistant ( hydrophobic ). Most factory-applied treatments are fluoropolymer based; these applications are quite thin and not always effective. Durable water repellents are commonly used in conjunction with waterproof breathable fabrics such as Gore-Tex to prevent the outer layer of fabric from becoming saturated with water. This saturation, called 'wetting out,' can reduce the garment's breathability (moisture transport through the breathable membrane) and let water through. As the DWR wears off over time, re-treatment is recommended when necessary. Many spray-on and wash-in products for treatment of non-waterproof garments and re-treatment of proofed garments losing their water-repellency are available.

Contents

Methods for factory application of DWR treatments involve applying a solution of a chemical onto the surface of the fabric by spraying or dipping, or chemical vapor deposition (CVD). The advantages of CVD include reducing the use of environmentally harmful solvents; requiring less DWR; and an extremely thin waterproof layer that has less effect on the natural look and feel of the fabric.

Some researchers have suggested that the use of PFASs in water-repellent clothing is over-engineering, and comparable performance can be achieved using specific silicon- and hydrocarbon-based finishes. [1] [2]

Re-treating garments

Top part of the fabric has been ironed after re treatment washing and this heat application has revitalized the repellency of water. Bottom part of the fabric has not been ironed after re treatment washing and the water is still wetting out the fabric. Water repellent shell layer jacket.jpg
Top part of the fabric has been ironed after re treatment washing and this heat application has revitalized the repellency of water. Bottom part of the fabric has not been ironed after re treatment washing and the water is still wetting out the fabric.

Certain types of fabrics need to be re-treated to maintain water-repellency, as fluoropolymers decompose over time when exposed to water and chemicals. [3] Washing the garment with harsh detergents usually accelerates DWR loss; in addition, soaps often leave a residue which attracts water and dirt. [4] On the other hand, rain water or salt water affects DWRs less significantly.[ citation needed ] Affected garments can be treated with a 'spray-on' or 'wash-in' treatment to improve water-repellency. In some cases heat treatment can reactivate the factory applied repellent finish and aid in the repelling of water, and other liquids such as oils. On the other hand, some DWR products do not require heat treatment to be activated, and sometimes DWR treatments can be revitalized simply by washing the fabric with a suitable cleaner.

Cravenette

Cravenette was an old process to make cloths water-repellent. It was a performance finish that repelled water. [5] [6] [7] [8] [9] [10] Various U.S.-based suppliers, such as A. Murphy, W.G. Hitchcock, and H. Herrmann, were offering Cravenette-treated cloths in the early 20th century. [11]

See also

Related Research Articles

<span class="mw-page-title-main">Gore-Tex</span> Trademark for a waterproof, breathable fabric

Gore-Tex is W. L. Gore & Associates's trade name for waterproof, breathable fabric membrane. It was invented in 1969. Gore-Tex blocks liquid water while allowing water vapor to pass through and is designed to be a lightweight, waterproof fabric for all-weather use. It is composed of expanded PTFE (ePTFE). A stretched out form of the PFAS compound polytetrafluoroethylene (PTFE). Gore-Tex products free of "PFC of environmental concerns" repellent coating lacks the ability to repel oil that "Gore DWR" provided.

<span class="mw-page-title-main">Raincoat</span> Waterproof coat

A raincoat is a waterproof or water-resistant garment worn on the upper body to shield the wearer from rain. The term rain jacket is sometimes used to refer to raincoats with long sleeves that are waist-length. A rain jacket may be combined with a pair of rain pants to make a rainsuit. Rain clothing may also be in one piece, like a boilersuit. Raincoats, like rain ponchos, offer the wearer hands-free protection from the rain and elements; unlike the umbrella.

<span class="mw-page-title-main">Waterproofing</span> Process of making an object or structure waterproof or water-resistant

Waterproofing is the process of making an object or structure waterproof or water-resistant so that it remains relatively unaffected by water or resisting the ingress of water under specified conditions. Such items may be used in wet environments or underwater to specified depths.

<span class="mw-page-title-main">Waterproof fabric</span> Textile that resists moisture penetration

Waterproof fabrics are fabrics that are, inherently, or have been treated to become, resistant to penetration by water and wetting. The term "waterproof" refers to conformance to a governing specification and specific conditions of a laboratory test method. They are usually natural or synthetic fabrics that are laminated or coated with a waterproofing material such as wax, rubber, polyvinyl chloride (PVC), polyurethane (PU), silicone elastomer, or fluoropolymers. Treatment could be either of the fabric during manufacture or of completed products after manufacture, for instance by a waterproofing spray. Examples include the rubberized fabric used in Mackintosh jackets, sauna suits, and inflatable boats.

Windstopper is a windproof breathable fabric laminate made by W. L. Gore & Associates. One of its most common applications is a lamination with polar fleece, to compensate for fleece's lack of wind resistance.

<span class="mw-page-title-main">Nonwoven fabric</span> Sheet of fibers

Nonwoven fabric or non-woven fabric is a fabric-like material made from staple fibre (short) and long fibres, bonded together by chemical, mechanical, heat or solvent treatment. The term is used in the textile manufacturing industry to denote fabrics, such as felt, which are neither woven nor knitted. Some non-woven materials lack sufficient strength unless densified or reinforced by a backing. In recent years, non-wovens have become an alternative to polyurethane foam.

Layered clothing is the wearing of multiple garments on top of each other.

Ventile, is a registered trademark used to brand a special high-quality woven cotton fabric first developed by scientists at the Shirley Institute in Manchester, England. Originally created to overcome a shortage of flax used for fire hoses and water buckets, its properties were also useful for pilots' immersion suits, but expensive and leaky if exposed to sweat or oils.

<span class="mw-page-title-main">Conservation and restoration of textiles</span> Processes by which textiles are cared for and maintained to be preserved from future damage

The conservation and restoration of textiles refers to the processes by which textiles are cared for and maintained to be preserved from future damage. The field falls under the category of art conservation, heritage conservation as well as library preservation, depending on the type of collection. The concept of textile preservation applies to a wide range of artifacts, including tapestries, carpets, quilts, clothing, flags and curtains, as well as objects which "contain" textiles, such as upholstered furniture, dolls, and accessories such as fans, parasols, gloves and hats or bonnets. Many of these artifacts require specialized care, often by a professional conservator.

Nikwax Analogy is a two-component fabric system for weatherproof clothing based on "biomimicry" of fur.

<span class="mw-page-title-main">Finishing (textiles)</span> Manufacturing process

In textile manufacturing, finishing refers to the processes that convert the woven or knitted cloth into a usable material and more specifically to any process performed after dyeing the yarn or fabric to improve the look, performance, or "hand" (feel) of the finish textile or clothing. The precise meaning depends on context.

Digital textile printing is described as any ink jet based method of printing colorants onto fabric. Most notably, digital textile printing is referred to when identifying either printing smaller designs onto garments and printing larger designs onto large format rolls of textile. The latter is a growing trend in visual communication, where advertisement and corporate branding is printed onto polyester media. Examples are: flags, banners, signs, retail graphics.

Wet Processing Engineering is one of the major streams in Textile Engineering or Textile manufacturing which refers to the engineering of textile chemical processes and associated applied science. The other three streams in textile engineering are yarn engineering, fabric engineering, and apparel engineering. The processes of this stream are involved or carried out in an aqueous stage. Hence, it is called a wet process which usually covers pre-treatment, dyeing, printing, and finishing.

<span class="mw-page-title-main">Superhydrophobic coating</span> Water-repellant coating

A superhydrophobic coating is a thin surface layer that repels water. It is made from superhydrophobic (ultrahydrophobicity) materials. Droplets hitting this kind of coating can fully rebound. Generally speaking, superhydrophobic coatings are made from composite materials where one component provides the roughness and the other provides low surface energy.

<span class="mw-page-title-main">Fluorochemical industry</span> Industry dealing with chemicals from fluorine

The global market for chemicals from fluorine was about US$16 billion per year as of 2006. The industry was predicted to reach 2.6 million metric tons per year by 2015. The largest market is the United States. Western Europe is the second largest. Asia Pacific is the fastest growing region of production. China in particular has experienced significant growth as a fluorochemical market and is becoming a producer of them as well. Fluorite mining was estimated in 2003 to be a $550 million industry, extracting 4.5 million tons per year.

Organosilicon water repellent:

Wrinkle-resistant or permanent press or durable press is a finishing method for textiles that avoids creases and wrinkles and provides a better appearance for the articles. Most cellulosic fabrics and blends of cellulosic rich fabrics tend to crease or wrinkle. A durable press finish makes them dimensionally stable and crease free. The finishing includes chemical finishing as well as mechanical finishing. Wrinkle-resistant finishes were developed in the early 20th century, as a way to deal with fabrics derived from cotton, rayon, and linen, which were found to wrinkle easily and retain the wrinkles. These treatments have a lasting effect on the fabric. Synthetics like polyester, nylon, acrylic and olefin, have a natural resistance to wrinkles and a greater stability since they do not absorb water as efficiently.

<span class="mw-page-title-main">Fabric treatment</span>

Fabric treatments are processes that make fabric softer, or water resistant, or enhance dye penetration after they are woven. Fabric treatments get applied when the textile itself cannot add other properties. Treatments include, scrim, foam lamination, fabric protector or stain repellent, anti microbial and flame retardant.

<span class="mw-page-title-main">Textile performance</span> Fitness for purpose of textiles

Textile performance, also known as fitness for purpose, is a textile's capacity to withstand various conditions, environments, and hazards, qualifying it for particular uses. The performance of textile products influences their appearance, comfort, durability, and protection. Different textile applications require a different set of performance parameters. As a result, the specifications determine the level of performance of a textile product. Textile testing certifies the product's conformity to buying specification. It describes product manufactured for non-aesthetic purposes, where fitness for purpose is the primary criterion. Engineering of high-performance fabrics presents a unique set of challenges.

<span class="mw-page-title-main">Chemical finishing of textiles</span> Chemical finishing methods that may alter the chemical properties of the treated fabrics

Chemical finishing of textiles refers to the process of applying and treating textiles with a variety of chemicals in order to achieve desired functional and aesthetic properties. Chemical finishing of textiles is a part of the textile finishing process where the emphasis is on chemical substances instead of mechanical finishing. Chemical finishing in textiles also known as wet finishing. Chemical finishing adds properties to the treated textiles. Softening of textiles, durable water repellancy and wrinkle free fabric finishes are examples of chemical finishing.

References

  1. Philippa J. Hill, Mark Taylor, Parikshit Goswami, Richard S. Blackburn. "Substitution of PFAS chemistry in outdoor apparel and the impact on repellency performance." Chemosphere, 2017, 181, 500-507. doi : 10.1016/j.chemosphere.2017.04.122
  2. Steffen Schellenberger, Philippa J. Hill, Oscar Levenstam, Phillip Gillgard, Ian T. Cousins, Mark Taylor, Richard S. Blackburn. "Highly fluorinated chemicals in functional textiles can be replaced by re-evaluating liquid repellency and end-user requirements." Journal of Cleaner Production, 2019, 217, 134-143. doi : 10.1016/j.jclepro.2019.01.160
  3. Lower, Stephen (2 July 2014). "10.2: The Liquid State". UC Davis ChemWiki. Retrieved 13 September 2015.
  4. Fowler, Will. "How to Re-Treat Garments". Sani-Tred. Retrieved 13 September 2015.
  5. "Definition of CRAVENETTE". www.merriam-webster.com. Retrieved 2021-07-24.
  6. Company, Sears, Roebuck and (1922). Catalog. Sears, Roebuck. p. 67.{{cite book}}: CS1 maint: multiple names: authors list (link)
  7. The Saturday Evening Post. 1952. pp. 64, 87.
  8. Winge, Jane (1981). Fabric Finishes. Cooperative Extension Service, North Dakota State University. p. 7.
  9. US1197304A,Pearson, Herbert P.,"Process for proofing hats of straw and the like and said product",issued 1916-09-05
  10. US2448247A,Bellwood, Carl R.,"Treatment of textiles with acyloxysubstituted aromatic acid salts",issued 1948-08-31
  11. Treasury, United States Department of the (1905). Treasury Decisions Under the Customs, Internal Revenue, and Other Laws: Including the Decisions of the Board of General Appraisers and the Court of Customs Appeals. U.S. Government Printing Office. p. 8.