{"id":59786,"date":"2026-03-23T14:23:33","date_gmt":"2026-03-23T13:23:33","guid":{"rendered":"https:\/\/eurotherm.eu\/drippings-in-industrial-liquid-coating-why-they-occur-and-how-to-eliminate-them\/"},"modified":"2026-04-15T17:24:01","modified_gmt":"2026-04-15T15:24:01","slug":"drippings-in-industrial-liquid-coating-why-they-occur-and-how-to-eliminate-them","status":"publish","type":"post","link":"https:\/\/eurotherm.eu\/en\/drippings-in-industrial-liquid-coating-why-they-occur-and-how-to-eliminate-them\/","title":{"rendered":"Drippings in industrial liquid coating: why they occur and how to eliminate them"},"content":{"rendered":"\n\n
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\n A defect of film instability: analysis of drippings in the liquid coating process <\/h2>\n <\/div>\n <\/div>\n\n
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Dripping represents one of the most obvious and penalizing defects in liquid coating. With its characteristic precipitated drop appearance, immediately visible on the surface, it compromises aesthetics and, in the most critical cases, affects coating performance<\/strong>. <\/p>\n<\/h3>\n <\/div>\n <\/div>\n

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It is often attributed to operational errors, although this is a partial truth: the formation of drippings is in fact the result of an unachieved balance between paint behavior, application mode and process conditions. Understanding why they form therefore means approaching coating as an integrated system, in which paint viscosity, application parameters and plant configuration combine to determine film stability<\/strong>. It is on this front that defect prevention is played out. <\/p>\n <\/div>\n <\/div>\n \n

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The stability of the liquid film is governed by the balance between antagonistic forces: on the one hand, gravity, which tends to make the material flow, and on the other hand, surface tension and viscosity, which counteract its movement. Added to these are the dynamics of solvent evaporation, which change the rheology of the film over time. When this balance is altered-for example, by excess material, low viscosity, or too slow evaporation-the film loses cohesion and casting phenomena are triggered. <\/p>\n <\/div>\n <\/div>\n <\/div>\n\n <\/div>\n <\/div>\n <\/div>\n<\/section>\n\n\n

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\n How drippings form: the behavior of the liquid film <\/h2>\n <\/div>\n <\/div>\n\n
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From a physical point of view, dripping or dripping of liquid paint occurs when the newly applied film loses its stability and, under the effect of gravity, flows along the surface of the workpiece before reaching a sufficient setting condition.<\/p>\n<\/h3>\n <\/div>\n <\/div>\n

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At the time it is deposited, the paint is in a fluid state(wet film<\/strong>) and must pass through a transient phase in which the atomized droplets coalesce (coalescence), solvents begin to evaporate, and viscosity gradually increases. If this process is not balanced, the force of gravity prevails over the surface tension and viscosity of the product, generating: <\/p>\n