Adhesive multiple-layer

Adhesive, multiple-layer—A film adhesive, usually supported with a different adhesive composition on each side, designed to bond dissimilar... 

One type of thick hardwood plywood stiU available is imported from the northern Scandinavian countries and is generally known as Finnish birch. Characteristically, these plywoods are manufactured using multiple layers of veneer of the same thickness, about 1.5 mm (1 /16 in.), and bonded with a urea—formaldehyde or melamine—urea—formaldehyde adhesive. 

Habitrol (102), co-developed by Lohmarin Therapie Systeme and Ciba-Geigy Ltd., and marketed by Ciba-Geigy, consists of an impermeable backiag laminate with a layer of adhesive and a nonwoven pad to which a nicotine solution is appHed (103). Multiple layers of adhesive on a release liner are then laminated on the patch. The systems come ia 10, 20, and 30 cm sizes corresponding to 7, 14, and 21 mg/day, respectively, deUvered over 24 hours. 

Verification film has drawbacks that render it useless for some assemblies. For bonded assemblies with complicated tooling and/or multiple layers of adhesive, the additional thickness of the release film plies can cause the verification film to be non-representative of an actual bonded assembly. Details can be moved out of their normal positions Just enough to prevent them from fitting coirectly or tooling from performing correctly, resulting in false indications of problems... 

Thermosetting resin pipe can be joined with mechanical joints or adhesive-bonded Joints. Mechanical joints are generally a variation of gasketed bell-and-spigot joints and may be either nonrestrained or self-restrained. Adhesive-bonded joints are typically bell-and-spigot or butt-and-strap. Butt-and-strap joints join piping components with multiple layers of resin-saturated glass reinforcement. 

Fig. I. Single-drum dryer (atmospheric). Dryers of this type may be dip or splash fed (not shown), or, as shown, equipped with applicator rolls. The latter is particularly effective for drying high-viscosity liquids or pasty materials, such as mashed potatoes, applesauce, fruit-starch mixtures, gelatin, dextrine-type adhesives, and various star dies. The applicator rolls eliminate void areas, permit drying between successive layers of fresh material and (omi me product sheet gradually. While single applications may dry to a lacy sheet or flakes, the multiple layers generally result in a product of uniform thickness and density with minimum dusting tendencies. (Bujiovak Division, BlawKnox Food Chemical Equipment. Inc)...

Principles (Technique 24). Our skin patch design consists of multiple layers of fabric webs at varying angles with a breathable, waterproof cover material and a hypoallergenic adhesive. 

Production of permeation-proof plastic fuel tanks can be realized using coextrusion with mbular die systems, followed up by hollow article extrusion blow molds. Using slit dies, multiple-layer, flat films or plates can be produced, which can then be deep-drawn. When the melt is united before the die, oxidizing gas can be blown into the airstream as an adhesion promoter, or adhesion promoter layers can be extruded into the material by means of coextrusion. Using a rotating mass distributor, sheathing with spiral markings can be made for switch wires, tubes and marbled profiles. 

A common configuration involves sandwiching the polymer between two sheets of metal to make a true composite material. While such composites exhibit optimum damping characteristics, they necessarily have limited form-ability. Alternatively, damping tapes (Wollek, 1965) have found important applications. In these systems, the adhesive serves also as the damping layer, and aluminum foil as the backing multiple layers may be applied with good effect. 

Time, assembly n. The time interval between the spreading of the adhesive on the adher-end and the application of pressure or heat, or both, to the assembly. Note—For assemblies involving multiple layers or parts, the assembly time begins with the spreading of the adhesive on the first adherend. (1) Open assembly time is the time interval between the spreading of the adhesive on the adherend and the completion of assembly of the parts for bonding. (2) Closed assembly time is the time interval between... 

Polyketones can be considered for both monolayer and multilayer constructions. The combination of good barrier properties, dimensional stability in the presence of fuel, and high burst pressures affords the possibility of a simple mono-layer construction. Should multiple layers be required, an inexpensive two-layer construction based on polyethylene and polyketones has been demonstrated to exhibit good strnctnral strength, barrier performance, and interlayer adhesion, both with and withont a tie layer. 

According to the final use, there exist different methods to measure the adhesive strength of polymeric materials. The island blister test and 90° peel test are particularly suited to determine the level of adhesion of very thin films in electronic applications. In the case of structural adhesives, the lap shear strength of three- or multiple-layer structures is a typical standard. 

The macroscopic composites are those in which one or both phases tend to have structures large enough to be easily seen with the naked eye. These include paint hlms (paint itself is usually a particulate composite), adhesive joints, and foams (e.g., the familiar polystyrene foams used for coffee cups because of their low heat transfer coefficient). The fabric laminates alternate layers of inorganic cloth and plastic. An important subclass usually has multiple layers of glass cloth or chopped fiber interspersed with layers of unsaturated polyester-styrene AB-cross-linked materials see Section 2.7.3. These sheet molding compounds are widely used for the hulls of pleasure boats, because they are light weight and very puncture resistant, as well as for automotive bodies see Section 13.9.1. 

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