| 摘要 |
PURPOSE:To dry a polyester with saved time and energy without deteriorating the resin, by applying mechanical energy to a low crystalline polyester resin to heat the resin at a constant temperature, agglutinating mutually the resin, cooling the agglutinated resin, disintegrating the resin into a granular shape, and drying the resin. CONSTITUTION:A polyester resin having 0-5cal/g calorific value is dried. In the process, the above-mentioned polyester resin is subjected to stroking and/or stirring and heated to a temperature of the softening point or above and lower than the melting point of the crystal to agglutinate mutually the above-mentioned polyester resin. The resultant agglutinated polyester resin is then cooled to a temperature below the softening point thereof, disintegrated into a granular shape, and dried. The cooling is preferably carried out by adding a small amount of a refrigerant, e.g. water or an alcohol thereto. In the disintegration after the cooling, the granular shape is as follows; <=100mm., preferably <=20mm. and >=1mm., preferably >=3mm. length of the longest part. |
