Liquid adhesives brushing

It is possible to mechanize brush methods by using hollow brushes through which the liquid adhesive is fed. This improves production rates and coating uniformity and cuts waste. Uniform films are generally difficult to achieve, but operators can become proficient with time. 

Because of this ready adherence to a substrate, molybdenum disulphide films can be produced in a wide variety of different ways, including flotation from the surface of a liquid, spraying, brushing or dipping in a volatile dispersant, bonding with adhesive or polymeric compounds, rubbing with powder, transfer, and vacuum sputtering. The nature of the initial film produced depends on the way in which it is applied, and all the important types will be discussed in subsequent chapters. 

Physical Form. Another method of distinguishing between adhesives is by physical form. The physical state of the adhesive generally determines how it is to be applied. Liquid adhesives lend themselves to easy handling via mechanical spreaders or spray and brush. Paste adhesives have high viscosities to allow application on vertical surfaces with little danger of sag or drip. These bodied adhesives also serve as gap fillers between two poorly mated substrates. 

Rowing is particularly useful for applying liquid adhesive to flat surfaces having irregular shapes. This method is superior to brushing in that it provides a more uniform adhesive film thickness and a higher production rate. In this method, the adhesive is fed under pressure through either a simple nozzle or a hollow brush. When a nozzle is used, the device is known as a flow gun. With a brush it is called a flow brush. The adhesive should be... 

Gold used for pottery is practically pure it is usually applied as liquid gold with a brush before firing. The liquid consists of some organic gold derivative in oil, with some suitable adhesive. 

Basically, the system is comprised of two liquid components - an oligomeric liquid blend (usually acrylic), and a dilute solution of an often proprietary free radical initiator or activator. Application methods are similar to those used for contact adhesives the oligomeric portion is applied by brush, roller or spray to one surface, and the initiator solution is applied in a thin (quasi-monomolecular) film to the other surface. The two films are non-air inhibited and may be left open, unbonded for many hours with no adverse effect on subsequent bonding operations. 

Most acrylic adhesives are supplied as two high viscosity liquids or pastes that are mixed together, called Mix-in Accelerator systems. Some types can also optionally be cured by no-mix accelerator lacquers. Accelerators are low viscosity liquids which are brush or spray applied to one or both of the substrates being bonded. Following accelerator application, the unmixed adhesive is applied to the primed substrate. This method eliminates the need for premixing the adhesive and accelerator, which eliminates pot life concerns. 

Many workers have examined the effect of surfactants and polymers adsorbed on mica. For example, polymers such as poly(vinyl pyridine) and its copolymers have been adsorbed on mica and their interfacial interactions measured in liquid media. Forces measured between these surfaces are of much longer range and provided some evidence for the brush conformation of polymers. Other workers have used industrially generated polymer films mounted directly to the glass lenses in the SFA and examined their adhesion... 

In order to speed up setting on inactive surfaces a liquid activator solution is brushed or sprayed onto one of the inactive surfaces and the adhesive is applied to the other surface. When they are brought together setting com-... 

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