Sealant forming apparatus, sealant forming method, and method of manufacturing liquid crystal display device using the same

A sealant forming method comprising the following sequence:

• (1) discharging a sealant through a nozzle of a dispenser having a syringe to dispense the sealant on a substrate, wherein the dispenser includes a syringe, and a nozzle connected to a lower end of the syringe to discharge a sealant, wherein the syringe is connected to a central tube and, first and second tubes are diverged from the central tube in different directions;
• (2) restoring an atmospheric pressure through an atmospheric tube to the dispenser;
• (3) extracting at least a portion of the sealant remaining in the nozzle through an instantaneous suction tube connected to the syringe;
• (4) performing an additional suction process to prevent at least another portion of the sealant from moving down to an end of the nozzle through an additional suction tube connected to the syringe;
• and
• (5) measuring an amount of the sealant in the syringe to determine a level of pressure applied to the syringe,
• wherein the instantaneous suction tube is connected to the first tube and, the atmospheric tube, a dispensing tube and the additional suction tube are connected to the second tube;
• wherein the central tube includes an element for measuring an amount of the sealant included in the syringe to determine a level of pressure of vacuum applied to the syringe and wherein the element includes a pressure sensor connected to the central tube, a third tube diverged from the central tube, an empty syringe connected to the third tube, and a selection valve to control the turn-on/off state of the central tube and the third tube;
• wherein the dispensing tube, the atmospheric tube, the instantaneous suction tube and the additional suction tube have a dispensing valve, an atmospheric valve, an instantaneous suction valve and an additional suction valve therein, respectively;
• and
• wherein extracting at least a portion of the sealant remaining in the nozzle includes:
• switching off the dispensing valve, the atmospheric valve and the additional suction valve;
• and
• switching on the instantaneous suction valve.

A method for manufacturing an LCD device comprising:

• preparing first and second substrates;
• dispensing a sealant on at least one of the first and second substrates, wherein dispensing the sealant includes the following sequence:
• (1) discharging the sealant through a nozzle of a dispenser to dispense the sealant on the substrate, wherein the dispenser includes a syringe, and a nozzle connected to a lower end of the syringe to discharge a sealant, wherein the syringe is connected to a central tube and, first and second tubes are diverged from the central tube in different directions;
• (2) restoring an atmospheric pressure through an atmospheric tube to the dispenser;
• (3) extracting at least a portion of the sealant remaining in the nozzle through an instantaneous suction tube;
• (4) performing an additional suction process to prevent at least another portion of the sealant from moving down to an end of the nozzle through an additional suction tube connected to the syringe, wherein a dispensing tube, the instantaneous suction tube and the additional suction tube are connected to a central tube which is then connected to the syringe;
• (5) measuring an amount of the sealant in the syringe to determine a level of pressure applied to the syringe;
• and
• providing a liquid crystal layer to at least one of the first and second substrates, wherein the instantaneous suction tube is connected to the first tube and,
• the dispensing tube, the atmospheric tube and the additional suction tube are connected to the second tube and have a dispensing valve, an atmospheric valve, an instantaneous suction valve and an additional suction valve therein, respectively;
• wherein the central tube includes an element for measuring an amount of the sealant included in the syringe to determine a level of pressure of vacuum applied to the syringe and wherein the element includes a pressure sensor connected to the central tube, a third tube diverged from the central tube, an empty syringe connected to the third tube, and a selection valve to control the turn-on/off state of the central tube and the third tube;
• and
• wherein extracting at least a portion of the sealant remaining in the nozzle includes:
• switching off the dispensing valve, the atmospheric valve and the additional suction valve;
• and
• switching on the instantaneous suction valve.