“Multifunctional Cardboard Material” that retains freshness + resists high humidity + provides heat insulation + repels water + provides visual appeal. The function can be applied to agricultural crops, owers and seedlings. And more, not only does it prevent the cause of spoilage such as dew condensation due to the ionization effect but also utilizes the ionization effect exerts heat insulation when the difference between the temperature inside and outside exceeds 10°C.