Spatulas, knives, trowels

They may be sifted onto a preheated substrate. The powder, which falls onto the substrate, melts and adheres to it (called powder coating). The assembly is then mated and cured according to the recommended processes. 

A preheated substrate can also be dipped into the powder and then removed with an attached coating of adhesive (as in fluidized-bed coating). This method helps assure even powder distribution. 

The powder can be melted into a paste or liquid form and applied by conventional means. 

Powder adhesives are generally one-part epoxy-based systems that require heat and pressure to cure. They do not require metering and mixing, but must often be refrigerated to obtain maximum shelf life. Because coating uniformity is poor, large variations in joint strength may result with these adhesives. 

The use of dry adhesive films is expanding more rapidly than other forms because of the following advantages  

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Solution adhesives are applied at 10-25% total solids content by spray, doctor knife, reverse roll coater, roller, or by spatula or trowel. The adhesive is dried at room temperature or in air ovens, care being taken to eliminate the fire and health hazards associated with some solvents. 

Spatel, m. spatula trowel surfacer, spatelformig, a. spatula-shaped, spatulate. Spatelmesser, n, steel spatula (shaped Uke a knife). 

Independent of final adhesive viscosity, hand application, by spatula, palette knife or trowel, is often the favoured method. However, once mixed, low viscosity adhesives are frequently pumped to an applicator gun, which is often robotically controlled. Higher viscosity paste adhesives can make use of hand-held cartridge dispensers which not only mix the adhesive, as indicated above, but also can apply a bead or stripe of adhesive to the substrate, dependant on the design of the applicator head. 

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