Method of manufacturing liquid crystal display device with removal of contaminants after cleaning and drying
View Patent ↗Disclosed is a method of manufacturing a liquid crystal display device using a liquid crystal dispensation alignment method which includes steps of: removing inorganic ions and the like by performing a vacuum drying process on substrates after cleaning alignment layers on which a rubbing process has been performed; and removing foreign objects by performing any one of a process for sucking up foreign objects by use of a nozzle having a specialized shape and a process for blasting a gas to which ultrasonic waves have been applied against the foreign objects, before liquid crystal is dispensed. In addition, a temperature at which sealing material is cured completely is lowered in order to inhibit activation (migration) of organic matters and to thereby reduce visible defects such as alignment bright defects.
1. A method of manufacturing a liquid crystal display device, comprising the steps of:
preparing a pair of substrates on which alignment layers for liquid crystal display have been formed respectively;
performing a rubbing process on each of the alignment layers of the pair of substrates;
cleaning and drying each of the pair of substrates on which the rubbing process has been performed (hereinafter referred to as a “cleaning and drying step”);
removing contaminants on the surfaces of the respective alignment layers immediately after the cleaning and drying by performing a heated vacuum drying process for heating the pair of substrates at 100° C. or more in a low-pressure atmosphere of 1 Pa or less (hereinafter referred to as “contaminant removing step”);
spraying spacers onto the other of the pair of substrates and fixing said spacers thereon;
performing further contaminant removing steps by a suction process for sucking up contaminants on the pair of substrates by use of air flow to be generated in the vicinity of the edge of a nozzle having a specialized shape by reducing a pressure within the nozzle, and by a blowing process for removing contaminants on the pair of substrates by blowing air flow to which ultrasonic waves have been applied, and thereby securely removing rubbing residues and coagulations of spacers;
dispensing liquid crystal on the alignment layer of one of the pair of substrates on which the contaminant removing step has been performed (hereinafter referred to as a “liquid crystal dispensing step”); and
arranging the pair of substrates to face each other, and bonding the substrates by using sealing material after the liquid crystal dispensing step.
2. The method of manufacturing a liquid crystal display device according to claim 1 , wherein a process for curing the sealing material includes a temporary curing process to be carried out immediately after the pair of substrates subjected to the heated vacuum drying process are bonded, and a complete curing process to be performed after a desired gap is formed between the pair of substrates, and the complete curing process is performed at a temperature equal to or lower than phase transition temperature of the liquid crystal.