Tape formulation development

In Japan, to control greenhouse whitefly and cotton whitefly that infest vegetables and ornamentals in the greenhouse, a yellow plastic tape formulation containing pyriproxyfen was developed. The tape has been widely used as it can lower the population of whitefly for several months after installation, and the influence on natural enemies and pollinators is low, and so forth. The action mechanism in this system is that adults attracted by the yellow color touch the tape and take pyriproxyfen into the body. The hatching of oviposited eggs is strongly inhibited by ovicidal activity via adults [38, 39]. 

An emulsifiable concentrate and granules are sold as formulations containing pyriproxyfen. The tape formulation is also sold in Japan under the trade name of Lano . The physicochemical properties of the formulations are very good and storage stability is very good. Moreover, mixtures with various insecticides have also been developed and sold. 

Cables via the powder-in-tube (PIT) method The approach is especially suited to processing Bi-2223 into leads and cables for power applications. A silver or silver alloy tube, filled with the partially reacted precursor powders formulated to yield Bi-2223, is drawn down to a wire 1-2mm diameter. The wire is rolled into a tape if that is the required form, usually with a width-to-thickness ratio of approximately 10 1. The composite is then heated to 800-900 °C when the powder partially melts. The recrystallization process is controlled and the pure Bi-2223 phase develops with large grains oriented so that the Cu-O planes lie parallel to the silver surface to optimize Jc. 

T0 assure optimum conductance, the adhesive must be applied as thinly and uniformly as possible. To control the thicknesses bondlines, thermally conductive paste adhesives have been formulated with collapsible spacers. The spacers are reported to control bondline thickness to 1.2 mils. These adhesives were developed for stacked die packages, but may also be used to attach ICs and other devices to substrates in plastic EGAs, CSPs, and array packages based on flexible tape or plastic laminates.Bondline thicknesses and uniformity may also be achieved by using film or preform tape adhesives and controlling the applied pressure and heat during cure. 

The first step in the manufacture of a recording media product actually occurs weU before the coating commences research and development. The various chemists involved in the development effort determine the appropriate master formulation for a tape product of given performance parameters. Once this has been achieved, the formulation is then passed onto the manufacturing side for full-scale production. 

Structural Adhesives. Films of nitrile rubber/phenolic resins (i.e. tapes) have been employed in the aircraft industry for bonding metal to metal surfaces in both plain and honeycomb sandwich constructions. Several Wright Air Development Center reports " describe in detail the preparation of a nitrile rubber/phenolic resin tape, the metal surface preparation methods, and the methods of evaluating structural adhesives of this type. A formulation for a high-temperature liquid phenolic resin adhesive suitable for structural fabrication is given in Table 21. ... 

Polybutadiene, silieone and vinyl ether adhesives are also used oeeasionally in tape and label appheations. Solvent-borne adhesives usually give better performanee than water-borne or hot melt adhesives, but environmental laws limiting the volatile organic content (VOC) of products and the desire to reduce worker exposure to hazardous materials (i.e solvents) are hurting these products. Attempts are being made to reduce VOC by developing new formulation with solids contents of 60+% compared to the normal 30 to 40%. 

These polydiene-, polyacrylate- or silicone-based adhesives are generally formulated products (with waxes in order to lower the glass transition temperature, and tackifying resins to provide tack), used as self-adhesives, coated to materials such as paper, films, and polymer tapes, etc. The term Pressure-Sensitive Adhesive relates to the fact that pressure from a linger on the rear of the material to be affixed is all that is required in order to allow the adhesive mass to wet the substrate sufficiently and to adhere to it more or less strongly. Depending on the visco-elastic properties and the adhesion forces developed at the interface, various behaviors can be reached from nonpermanent in the case of Post-it to semipermanent in the case of dressings. 

Satisfactory formulations of pheromones that afford a constant release rate over a long period of time are not likely to be achieved without the cooperation of the chemical industry. Controlled release of pheromones is discussed in the Proceedings of a recent symposium (623). Fortunately, several organizations in the U. S. have been interested in the possibilities of the use of pheromone formulations on a commercial basis. One company (605) has supplied formulations for several investigators, and in addition has carried out extensive field tests with their own personnel. It has developed the use of hollow fibers, which are simply microcapillary reservoirs that serve to contain a vaporizable material and mediate evaporation of the material into the atmosphere . The fiber wall is essentially impermeable. One end is sealed, and the release rate essentially depends on diffusion from the surface of the liquid-vapor interface to the open end of the hollow fiber. Fibers are supplied in two forms. A tape form consists of a parallel array of fibers on an adhesive tape this form is used to establish point-source evaporators. The chopped fiber form is used for dissemination with a ground rig or from the air. 

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