WASHING METHOD OF FILTER

摘要

PROBLEM TO BE SOLVED: To provide an industrially useful washing method for fusing and filtering liquid crystalline polyester and then reusing a filter.SOLUTION: This method is for fusing and filtering liquid crystalline polyester using a filter whose filtration accuracy is 1 to 50 μm and then washing the filter. In the washing method of the filter, the filter is heated to a temperature satisfying the following requirement (a) or higher, and then alkali washing is performed. (a) At the temperature, melt viscosity of the liquid crystalline polyester becomes 500 Pa s or lower, measured by a flow property tester using a die having a nozzle diameter of 0.5 mm&phgr; and a nozzle length of 10 mm under the condition that a shear rate is 1,000(s).