Screen printing is a process that involves transferring ink through a mesh onto a substrate. The flow behavior of thick film ink depends on its viscosity and surface tension. Screen printing utilizes the shear thinning properties of inks, where viscosity decreases under the high shear stress of printing. Key variables in screen printing include screen mesh properties, machine settings, ink rheology, and squeegee materials and hardness. Screen printing is commonly used in the electronics industry to apply conductive pastes for applications like hybrid ICs, resistors, and electrodes for devices like electroluminescent lamps.