Controlled by pull-up speed and viscosity of coating liquid

Generally, a faster pull-up speed results in a thicker film, while a slower pull-up speed results in a thinner film.

Case a:When the pull-up speed is high and the viscosity of the coated liquid is high

The film thickness in this case is determined by the balance between viscous resistance and gravity.

h = C ηU ρg

Case b:When the pull-up speed is sufficiently slow and the viscosity of the coating liquid is low

The surface tension at a gas and liquid interface governs the film thickness, and the following relationship holds.

h = 0.94 ηU 2 3 γ 1 6 ρg

U is the pull-up speed (m/s)、;7 is viscosity (Pa・s = kg・m/s)、 ρ is density of coating liquid (kg/m3).
γ is the surface tension of a liquid (N/m).
g is gravitational acceleration (m/s2).
C is coefficient (0.8 for Newtonian fluid)
In dip coating, Newtonian fluid is basically used as the coating liquid.


The standard F and M series for R&D are equipped with calculation software as standard.

Please use it to calculate the theoretical of film Thickness.