Types of Conformal Coatings

This paper discusses a new type of conformal coating that is solventless, one-component and cured by a combination of UV and heat. 

We have described a new type of conformal coating which is shelf-stable, solventless, one-component, and rapidly cured by a combination of UV and heat. Once cured, this coating has very good electrical properties, thermal stress resistance, and hydrolytic stability. With the proper choice of solvents, all or a portion of the cured coating can be removed from a circuit board to repair the electronic parts. 

More information on the less common types of conformal coating may be found in IPC-HDBK-830. 

The most commonly used types of conformal coatings include ... 

An application that is becoming of increasing interest to the electronics and communications industries is that of encapsulation or conformal coatings. These coatings are better classified as adhesives or elastomers because normal types of surface coatings do not meet the end-use-requirements, which include resistance to environmental stress, electricity and aging. 

Special types of encapsulating coatings have been developed that are more effective than ordinary paint in keeping a contaminated area covered. These products must be flexible, abrasion resistant, chemical and water resistant, temperature resistant, and in conformance with fire code requirements. They are more expensive and more difficult to apply than ordinary paint, but are more difficult to dislodge and more effective at keeping the old paint covered up. Some states have certified specific products for covering lead paint. To find out if encapsulants have been certified in your state for lead abatement, call your state lead program, listed in Appendix A. 

The PECVD technique appears to be a unique method that allows for the implementation of Li-ion batteries with particularly sophisticated architecture. A new type of 3D microbatteries with anode or cathode post-arrays has been recently developed in the Tolbert Lab at University of California (Los Angeles). However, such systems require a solid electrolyte in the form of conformal coatings that will evenly cover the high aspect ratio electrodes. Plasma deposited polyethyleneoxide-hke electrolyte films, which are electronic insulating and can be intercalated with lithium ions, have been chosen to this end. Currently, these films are intensively investigated (Dudek, 2011). 

Any polymerization reaction in which the product of each elongation step can itself also undergo further polymerization. When the same types of bonds and/or conformational states that are present in the reactant(s) are generated within product(s) during elongation, the process is referred to as isodesmic polymerization. Such is the case for the indefinite polymerization of actin, tubulin, hemoglobin S, and tobacco mosaic virus coat protein. See Nudeation Protein Polymerization Actin Assembly Kinetics Microtubule Assembly Kinetics Microtubule Assembly Kinetics... 

Fig. 10.21. Schematic illustration of steps for forming a type of three-dimensional structure by nTP. Printing with a stamp that has a conformal coating of metal produces sealed...

Two types of coating materials are used in electrical and electronic equipments. One is conformal coating, the other is junction coating resin. These coating materials also occupy an important place in the electrical and electronic fields. 

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