Abstract: Empty open-top paint cans travelling along a conveyor are filled with paint and a measured amount of an anti-coagulant agent is showered on to the paint surface before closing the cans. The filling of the cans with paint is accomplished at a first processing station and the anti-coagulant is introduced and the closing of the cans is performed at a second processing station. The anti-coagulant dispensing apparatus is switch-activated and employs a shower head for dispensing predetermined quantities without splashing the paint in the cans. The switch is located on the side of the conveyor and is actuated by paint cans contacting the switch during conveyance.