Web processing

Nylon films are used in lamination or coated form to ensure heat sealabiHty and enhance barrier properties. The largest uses are as thermoforming webs for twin-web processed meat and cheese packagiag under vacuum or in an inert atmosphere. Other uses include bags for red meat, boil-ia-bags, bag-in-box for wine, and as the outer protective layer for aluminum foil in cookie and vacuum coffee packages. 

Air and oil filters are made by a dry-web process in which the filter paper is dried over heated metal dmms. The paper is saturated with the phenoHc resin solution, either off- or on-line, and dried in an oven advancing the resin to the B-stage (semicured). The sheet, containing 20—30% resin, is roUed and shipped to the filter-unit manufacturer, where the sheet is convoluted and the filter assembled and cured to the C-stage (fully cured). 

There are many excellent textbooks on the subject of distillation, however with the explosion of information on the World Wide Web, process engineers can now gain almost instant access to calculation methods and model simulations which will walk the engineer through the important design steps. The following Web sites are recommended to be reviewed and accessed by the reader. 

Many of the analytes of interest for solid phase chemical reference materials are the same as those in seawater, but the need for and the preparation of reference materials for suspended particulate matter and sediments is quite different. The low concentrations of many seawater species and the presence of the salt matrix create particular difficulties for seawater analyses. However while sediments frequently have higher component concentrations than seawater, they also have more complicated matrices that may require unique analytical methods. A number of particulate inorganic and organic materials are employed as paleoceano-graphic proxies, tracers of terrestrial and marine input to the sea, measures of carbon export from the surface waters to the deep sea, and tracers of food-web processes. Some of the most important analytes are discussed below as they relate to important oceanographic research questions. 

The advancement of low viscosity, radiation curable systems in the last two years has for the first time made gravure application of these systems a reality. Since many Industrial web processes (coating paper or film, laminating, metal coating, etc.) already employ gravure equipment, the availability of these new systems (1) has had major impact on the interest in electroncuring technology. 

Including food-web processes in quantitative models of carbon and nitrogen cycling of forest ecosystems. The competition between sapro-trophic and mycorrhizal fungi for resources is a key aspect of belowground functioning (Lindahl et al., 2002). Quite detailed computer models... 

Figure 16.3 Microbial food web processes sustain the marine N-cycle in the North Pacific trades biome. Shown are (A) a schematic view of the various sources, transformations and sinks for key N pools and...

Calendering is a popular method of rubber processing. It is also used in the production of films and in lamination of plastic film to substrates in a continuous web process. Hot-melt coating equipment is another version of calendering equipment used for production of plastic coated textile materials. 

Research and development in fluid jet technology led to its widespread use in film and web processing, mixers, reactors, and fiber processing. Applications to fibers alone includes Taslan bulked yams, jet piddlers, draw-jets, interlaced yams, bulk-crimped carpet fibers (BCF), and spunbonded products such as Reemay polyester, Typar polypropylene (PP), and Tyvek olefins. New fibers also were introduced Nomex aramid, especially suited for high-temperature applications Lycra spandex, an elastic textile yam Qiana nylon, with a silklike appearance and Kevlar aramid, used in products ranging from tires to bullet-resistant vests. 

Satas D. 1984 (Ed.). Web Processing and Converting Technology and Equipment. Van Nostrand Reinhold Publishing Co., New York. Articles by highly experienced authors on various modes of coating as well as related operations. More up-to-date and more nearly comprehensive than Booth s book, but just as purely technological and descriptive. 

Zappa (agents in UK are Web Processing (M/c) Ltd. Whaleybridge, Stockport) Italy... 

Arachne machine n. (1) A machine for producing loop-bonded nonwovens. The fabric is formed by knitting a series of warp yarns through a fiber web processed on a card. Also see bonding. (2) Stitch bonding. 

Soft-Aire, Tension control brakes-clutches, P/A Industries Inc., Web Processing Equipment Div. 

Buntin, R. R., Lohkamp, D. T. Melt Blowing-One-Step WEB Process for New Non-woven Products. Tappi, 1973, 56(4), 74-77. 

Highly suited for incontinence items. Thermally bonded laminates with cotton core and outer layer of MB and/or spunbonded (SB) webs process are designed by encapsulation of carded bleached cotton web with outer layers of MB PP and/or SB PP after extrusion process, prior to calendering. 

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