As the name implies, the insulated lunch kits have the function of keeping cold and heat. It is suitable for packaging all kinds of food, fresh food, medicine and other temperature-sensitive products. It is also known as ice pack in the industry. It is often used with phase change cold storage material (refrigerant) to achieve the purpose of keeping cold and heat.
The insulated lunch kit is usually composed of three layers, namely the outer layer, the insulated sandwich and the inner layer. The outer layer of Oxford cloth or nylon cloth, strong and wear-resistant. The insulation layer adopts EPE pearl cotton insulation material to keep cold and heat. This layer determines the insulation efficiency of the insulation bento lunch bag. Aluminum foil is used in the inner material, which is radiation resistant and easy to clean.
At present, the thermal insulation lunch bag is widely used in the market. The thermal insulation lunch bag can be used to solve the thermal insulation aging problem for food, fresh and other short distance cold and heat preservation. Compared with thermal insulation devices such as thermal insulation boxes, thermal insulation lunch bags have the characteristics of light and easy to fold, which can save space and reduce costs in transportation and storage. The shortcomings of heat preservation lunch bag is that the heat preservation time is limited, and the current use of pearl cotton material heat insulation performance is general and production should not be too thick. We can optimize the thermal preservation efficiency of insulated lunch bags from other perspectives, the following is for reference:
ⅰ. Material innovation
Of course, the most important material is the heat insulation layer. At present, the heat insulation layer of the bento lunch bag is selected as the thermal insulation medium. Because of the high thermal conductivity of the pearl cotton, the insulation efficiency is limited. Foreigners use the polyurethane foam as insulation layer, which can greatly improve the thermal insulation of lunch bags. Green cold chain packaging center developed namiki thermal insulation material instead of pearl cotton, thermal insulation performance can be comparable with the common XPS insulation box.
ⅱ. Structural innovation
From the perspective of structural optimization of thermal insulation lunch bag, it is necessary to consider the structural factors that affect the thermal insulation performance of thermal insulation lunch bag, such as no thermal insulation material at the joints of the adjacent surface of the thermal insulation lunch bag, no windproof structure at the zipper of the bag mouth, etc. These parts also generate a large amount of air convection heat transfer, resulting in the decline of thermal insulation performance.
Therefore, in the thermal insulation lunch bag structure design can be optimized. To use integrated thermal insulation lunch bag design, the use of soft insulation layer to reduce joint parts to improve the thermal insulation performance. The tongue windproof structure can be designed at the zipper around the bag mouth, and it can be fitted with hook and loop fasteners to make the zipper with double protection. In addition, in the thermal insulation layer structure design, it can be double layer insulation material filling, the outer layer and inner layer between the formation of the first insulation layer, and then inner layer and outer layer between the formation of a second insulation layer, using pearl cotton, environmental protection EVA, wool and other insulation materials to fill.
In short, the application of thermal insulation bento lunch bag has involved in people's daily life. When people are shopping, outing, having a picnic, they all can use thermal insulation lunch bag to solve the problem of food cold, heat preservation and preservation. The future thermal insulation bento lunch bag industry will pursue more lightweight, convenient, environmentally efficient products.