The surface of the carton of the packaging box has wrinkles and streaks of quality defects on the surface after calendering. It does not meet the requirements. If it cannot be remedied, it will be treated as waste, which will cause great economic losses.
Through many experiments, we found a solution to the problem. The specific method is: glazing the non-calendered cardboard after it is glazing, and then bake it once on the calender. The temperature and calendering At the same temperature, when the calender is hot-baked, no pressure can be applied. In the case of the calender belt drive, the cardboard is placed on the strip surface at the discharge end, and the surface is driven by the steel strip. The cardboard is brought into the drying tunnel and returned to the feed port of the calender. After such heat baking and calendering (ie, adding a glazing and a hot bake) followed by a normal calendering process, the wrinkles and stripes on the cardboard disappeared.
By the way, under normal circumstances, the temperature of calendering is generally controlled at 115°C～120°C, the pressure is controlled at 150～180kg/m2, and the speed is 6～10m/min. Of course, it is also necessary to use cardboard according to the site operation. The thickness of the material is properly adjusted and controlled. It is worth noting that, for the paper products to be calendered, there must be some choice in paper quality, otherwise the calender quality requirements cannot be achieved.