Dip-coating

Dip coating is an industrial coating process which is used, for example, to manufacture bulk products such as coated fabrics and condoms and specialised coatings for example in the biomedical field. Dip coating is also commonly used in academic research, where many chemical and nano material engineering research projects use the dip coating technique to create thin-film coatings.

The earliest dip-coated products may have been 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 condom-making, a former is dipped into the 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 in the case of a condom.

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.^[1]