Dip coating is the precision controlled immersion and withdrawal of any substrate into a reservoir of liquid for the purpose of depositing a layer of material. Dip coating is a process used in Industries to manufacture bulk products such as coated fabrics, specialized coatings in the biomedical field etc. It is used in academic research as well, where many chemical and nano material engineering research projects use the dip coating technique to create thin-film coatings. The earliest dip-coated products are candles. For flexible laminar substrates such as fabrics, dip coating may be performed as a continuous roll-to-roll process. For coating a 3D object, it may simply be inserted and removed from the bath of coating. For some products, such as early methods of making candles, the process is repeated many times, allowing a series of thin films to bulk up to a relatively thick final object.
The final product may incorporate the substrate and the coating, or the coating may be peeled off to form an object which consists solely of the dried or solidified coating. As a popular alternative to Spin coating, dip-coating methods are frequently employed to produce thin films from sol-gel precursors for research purposes, where it is generally used for applying films onto flat or cylindrical substrates.
For more information, read on:
https://en.wikipedia.org/wiki/Dip-coating
https://www.biolinscientific.com/measurements/dip-coating
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