The box liner material is usually EPE foam foil or bubble foil. The material is hot pressed to form a finished product with good thermal insulation performance and waterproof and easy to clean. Compared with the previous vacuum frozen food directly into the carton, with the addition of inner bag, the product regardless of the thermal insulation and cold effect time is greatly extended, and the cold liquefied water droplets will not directly contact with the box, greatly improving the recycling utilization rate of the carton.