Compared with acrylic cast sheet, acrylic extruded sheet has lower molecular weight and slightly weaker mechanical properties. After the sheet is produced, during the cooling and temperature change process, a strong thermal stress is generated. When the thermal stress exceeds the yield strength of the material itself, it is It will cause deformation. Generally, the deformation of the thin plate is large, and the thick plate is relatively better. Usually, when placing the plates in the warehouse, the ambient temperature difference should not be too large, the ventilation and dryness should be avoided, and the plates should be packed neatly. The surrounding area is wrapped with PE film to reduce water loss, which will delay the deformation of the sheet.