Surface coated fabrics

The properties of a filter medium can be changed by layering a second medium onto the surface of the first to make a composite medium. Examples of these media include surface coated fabrics, laminated media (where two or more woven or nonwoven materials are fixed together, either firmly or loosely) and multilayer weaves. 

Surface coatings applied to filter fabrics can enhance one or more of the filtration properties of the fabric. The coating may be sprayed on as a liquid or laid down as a sheet which is then bonded to the fabric. Microporous polymer coatings may be used to provide a smoother and fine aperture size to the fabric surface, which may enable easier detachment of the cake and prolong the lifetime of the medium. 

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Industrial surface coating fabric Industrial surface coating paper... 

Vinyl-Coated Fabrics. Leather substitutes are designed to imitate the appearance of leather with its grain surface. This requirement has been accomphshed by coating substances that are capable of forming a uniform film, and was first met by plasticized poly(vinyl chloride) (PVC). A leather-like material termed vinyl-coated fabric was developed in the 1930s in the United States and Germany. Shortages of leather after World War 11 spurred the expansion of this material. 

In the wet system, manufacture proceeds as foUows (/) a 7—20% polyurethane solution of DMF is appHed onto a fabric and immersed in water containing 0—10% of DMF for coagulation (2) the coated fabric is washed and dried (4) the surface is finished by the dry system. For the substrate, a woven or knit fabric which has been bmshed on its surface is often used to improve appearance, resistance to grain break, and feel. 

Melamine—Formaldehyde Resins. The most versatile textile-finishing resins are the melamine—formaldehyde resins. They provide wash-and-wear properties to ceUulosic fabrics, and enhance the wash durabiHty of flame-retardant finishes. Butylated melamine —formaldehyde resins of the type used in surface coatings may be used in textile printing-ink formulations. A typical textile melamine resin is the dimethyl ether of trimethylolmelamine [1852-22-8] which can be prepared as follows ... 

Post Treatment. Coated fabrics can be decorated and protected by applying inks and coatings to the surface. Often the finished product is an attempt to simulate the look of leather. This is most common ia upholstery, luggage, and athletic bag constmctions where natural leather is the main competitor, although any number of decorative effects can be created and are used ia produciag products such as waHcoveriag. 

Commercially available electrodes are produced in coated fabricated steel housings in which the electrodes are retained by hard-setting epoxy resins. Connecting cables pass from the housing through cable glands and are either installed in conduits to the surface or are wire armoured for protection. 

Many industrial yams have specific surface function requirements. For technical yams the market share for composites or coated fabrics is almost 70%. Furthermore, textile applications also can benefit from a special surface treatment in order to improve the water repellency. Capillary membranes for dialysis, however, have totally different requirements enhanced biocompatibility of the membranes is needed.4-6... 

Linings and liquid surface coating systems for architectural fabrics. .. 

Fig. 9.1 A schematic illustration of surface coatings with their typical thickness ranging from angstroms to micrometers. Selected are monomolecular layers fabricated by the transfer of Langmuir-Blodgett (LB) films onto solid substrates (1) self-assembled monolayers (SAMs) (2) multilayers thereof (3) polymer-...

Additional curing is often achieved with sulfur, peroxide, or maleimide formulations. Chloro-sulfonated polyethylene has improved resistance to oil, ozone, and heat compared to many other elastomers. Applications include harrier membranes and liners, surface coatings on fabrics, automobile air-conditioner hose, electrical cable insulation, and spark-plug boots [Andrews and Dawson, 1986],... 

Photocatalytic bactericidal activity experiments were performed using E. coli with untreated and TiO -coated fabric and aluminum foil (Fig. 1.6) and with or without UV-A irradiation. Photocatalytic bactericidal properties of TiO -coated fabric and foil were observed after 30 min. The most distinctive difference between coated and UV-irradiated materials was observed initially. This is a clear demonstration of the photocatalytic ability of TiO and accelerated surface decontamination. We observed complete bacteria killing only on aluminum foil coated with TiO, and partial killing on the coated fabric. These results suggest that TiO coated materials have bactericidal properties. 

Another group of chlorinated hydrocarbons comprises those made from paraffin wax. Major applications are in extreme pressure lubricants and as extenders and plasticizers in surface coatings and in vinyl plastics. The chlorinated waxes were also widely applied in flameproofing cotton fabrics, which led to large consumption by the military. It is believed that current military requirements for flame-resistant fabrics will be met by vinyl sheeting of vinyl-coated textile products, so that the World War II demand for the halogenated waxes will not be repeated. 

In the past, mica has been the material of choice for the interacting surfaces because of the ease of handling and since molecularly smooth surfaces can be fabricated mica surface coated with a thin film of other materials (e.g., lipid monolayers or bilayers, metal films, polymer films, or other macromolecules such as proteins) can also be used. The use of alternative materials such as molecularly smooth sapphire and silica sheets and carbon and metal oxide surfaces is also being explored. 

To finish the surfaces of fabrics or -leather prepared with gutta-percha or its combinations, he coats them with transparent oolors, made fey combining the colors with oils or varnishes. His mode of operating is as I follows)—Suppose the fabric is coated with gutta- percka, and animal charcoal or lamp-black, the color j would be a dull black to improve upon this, he takes j... 

The application of paint is practiced within most fabricated metal industries. Surface coatings are used wherever it is desired to provide decoration, protection, and/or safety marking to a product or item. Most paint coatings for fabricated metal products are solvent based although many shops are replacing these with water based materials. Because many of the paints contain heavy metals, reducing paint wastes also results in reducing metal wastes. 

An inclined plane method is specified for coated fabrics in BS342439. The test piece is attached to a sled resting on an inclined plane which is covered with the other surface to be tested. The inclination of the plane is varied until sliding takes place. This is probably the simplest form of friction test but not an accurate one and, of course, cannot operate at any given velocity. 

Continuous-flow microreactors were successfully fabricated by etching channels in silicon and immobilizing urease onto channel surfaces by a layer-by-layer self-assembly technique. Preliminary results show urea conversion. The potential advantages of this surface-coating technique in microreactors warrant continued investigation. 

Calendering, as mentioned earlier, is used to produce sheets, slabs, and certain types of coated fabrics. The grades most suitable for calendering are those with low viscosity. Processing aids are necessary to improve surface smoothness and a good release of sheets from the rolls. 

Aqueous dispersions of these two melt-processible perfluoropolymers are processed in a way similar to PTFE dispersion. FEP dispersions can be used for coating fabrics, metals, and polyimide films. They are very well suited for bonding seals and bearings from PTFE to metallic and nonmetallic components and as nonstick and low-friction coatings for metals.16 FEP can be fused completely into a continuous film in approximately 1 min at 400°C (752°F) or 40 min at 290°C (554°F).17 PFA is used to coat various surfaces, including glass fabric, glass, and metals. 

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