Printing device, preferably a 3D printer, comprising at least one printing nozzle which is designed to eject a flowable material through at least one ejection opening in the direction of a preferably horizontal working surface, wherein the printing nozzle has a fixed printing nozzle frame and a printing nozzle head, with the ejection opening, which is movable relative to the printing nozzle frame, preferably in height, wherein the printing nozzle is designed to move the printing nozzle head relative to the printing nozzle frame, preferably in height, between an open position, in which a flow of the flowable material through the ejection opening is permitted, and a closed position, in which a flow of the flowable material through the ejection opening is not permitted, by means of a drive, preferably by means of a piezoelectric or pneumatic drive, wherein the ejection opening of the printing nozzle head is spaced further apart from the working surface in the closed position than in the open position, characterized in that the printing nozzle frame has at least two sealing surfaces and the printing nozzle head has at least two sealing surfaces, which are formed in pairs opposite each other such that, in the open position one pair of sealing surfaces (30d, 31d) is spaced apart from each other and forms a transition region therebetween, through which the flowable material is permitted to flow toward the ejection opening, and the other pair of sealing surfaces (30d, 31d) is sealed together so that the flowable material is not permitted to flow toward an outlet opening (30g; 31g) between the two sealing surfaces (30d, 31d), and in the closed position one pair of sealing surfaces (30d, 31d) is sealed together so that the flowable material is not permitted to flow toward the ejection opening between the two sealing surfaces (30d, 31d), and the other pair of sealing surfaces (30d, 31d) is spaced apart from each other and forms a transition region therebetween, through which the flowable material is permitted to flow toward the outlet opening (30g; 31g). comprising at least one printing nozzle which is designed to eject a flowable material through at least one ejection opening in the direction of a preferably horizontal working surface, wherein the printing nozzle has a fixed printing nozzle frame and a printing nozzle head, with the ejection opening, which is movable relative to the printing nozzle frame, preferably in height, wherein the printing nozzle is designed to move the printing nozzle head relative to the printing nozzle frame, preferably in height, between an open position, in which a flow of the flowable material through the ejection opening is permitted, and a closed position, in which a flow of the flowable material through the ejection opening is not permitted, by means of a drive, preferably by means of a piezoelectric or pneumatic drive, wherein the ejection opening of the printing nozzle head is spaced further apart from the working surface in the closed position than in the open position, characterized in that the printing nozzle frame has at least two sealing surfaces and the printing nozzle head has at least two sealing surfaces, which are formed in pairs opposite each other such that, in the open position one pair of sealing surfaces (30d, 31d) is spaced apart from each other and forms a transition region therebetween, through which the flowable material is permitted to flow toward the ejection opening, and the other pair of sealing surfaces (30d, 31d) is sealed together so that the flowable material is not permitted to flow toward an outlet opening (30g; 31g) between the two sealing surfaces (30d, 31d), and in the closed position one pair of sealing surfaces (30d, 31d) is sealed together so that the flowable material is not permitted to flow toward the ejection opening between the two sealing surfaces (30d, 31d), and the other pair of sealing surfaces (30d, 31d) is spaced apart from each other and forms a transition region therebetween, through which the flowable material is permitted to flow toward the outlet opening (30g; 31g).