Polyester film encapsulation

Microcapsules are used in several film coatings other than carbonless paper. Encapsulated Hquid crystal formulations coated on polyester film are used to produce a variety of display products including thermometers. Polyester film coated with capsules loaded with leuco dyes analogous to those used in carbonless copy paper is used as a means of measuring line and force pressures (79). Encapsulated deodorants that release their core contents as a function of moisture developed because of sweating represent another commercial appHcation. Microcapsules are incorporated in several cosmetic creams, powders, and cleansing products (80). 

Polyester film encapsulation Library of Congress Washington, DC, 1980. 

Curatorial Care of Works of Art on Paper. Intermuseum Conservation Association, Oberlin, Ohio, p.73). If the inks are not stable in water but are stable to methanol, the tapas will be treated with WEI T O Solution 3. If the inks are unstable in both water and methanol, the tapas will be encapsulated in Mylar polyester film and no further treatment will be attempted. 

The state of the art for the conservation of large collections of items can be expressed at the Library of Congress in two words "phased preservation. This entails better housing for collections, better protection for individual items by use of alkaline folders or mats and boxes, or polyester film folders and encapsulations, and better surveying to establish needs for future treatment. Necessary treatments may then be given orders of priority and scheduled for execution in phases over an appropriate period of time. 

In 1973, the Library of Congress Preservation Office initiated the use of polyester film encapsulation as a technique for the conservation of maps, manuscripts, posters, and carefully selected works of art on paper. 

Polyester Film Encapsulation U.S. Libr. Congr. Preserv. Off. Washing-... 

Metall ic fibers are defined as fibers composed of metal, plastic-coated metal, or metal-coated plastic. Single-component metall ic fibers for textile usage are fine drawn filaments of metal which can be spun and woven on normal textile machinery. These metallic fibers possess the properties of the metal from which they are formed. Multicomponent metallic fibers are more commonly used in textiles and are usually made from flat aluminum filaments surrounded with or bonded between clear layers of polyester, cellophane, or cellulose ester or from polyester film which has been metallized through vacuum deposition of aluminum and then encapsulated in polyester. In general, the properties of these fibers resemble the properties of the plastic film used to form the multicomponent fiber. The fibers are generally weak and easily stretched but can be used for decorative purposes and for applications where electrical conductivity and heat resistance are important. Trade names for metallic fibers include Brunsmet and Lurex. 

Encapsulation. Immobilization of enzymes by encapsulation within semipermeable structures dates back to the 1970s. There are three fundamental variations of this approach. In coacervation, aqueous microdroplets containing the enzyme are suspended in a water-immiscible solvent containing a polymer, such as cellulose nitrate, polyvinylacetate, or polyethylene. A solid film of polymer can be induced to form at the interface between the two phases, thereby producing a microcapsule containing the enzyme. A second approach involves interfacial polymerization in which an aqueous solution of the enzyme and a monomer are dispersed in an immiscible solvent with the aid of a surfactant. A second (hydrophobic) monomer is then added to the solvent and condensation polymerization is allowed to proceed. This approach has been used extensively with nylons, but is also applicable to polyurethanes, other polyesters, and polyureas. 

Definition Copolymer of ethylene and calcium acrylate monomers Formula (C3H4O2 C2H4)x xCa Uses Film-former processing and performance additive improves dispersion of additives in plastics adhesion to variety of substrates encapsulant for personal care prods. low m.w. ionomer flatting agent that reduces gloss in polyester powder coatings In food-pkg. adhesives... 

Another interesting example is polycondensation reactions to procedure polyesters and polyamides (73). Sharma (3,4) discusses also some aspects of interfacial polycondensation here, for instance, the diacyl chloride, dissolved in a water immiscible organic solvent, may be contacted with hexamethylene diamine to proceduBs the polyamide. Nylon 66. Since diamine is very soluble in the organic phase and the reaction is very fast, the reaction occurs probably in organic phase, therefore acyl chloride cannot get an opportunity to get into aqueous phase where concurrent hydrolysis would have occured Usually, a film of polymer is formed on the organic phase droplets disposed in water and thus droplets are encapsulated and interfacial area measurements can well be envisaged. 

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