The air-activated product is different from other regular product’s, such as air-activated hand warmer, toe warmer, foot insole warmer, medical heat patch and so on, it will start to react and release heat immediately once contact the oxygen of air, so that the requirements for the quality and sealing property of packing bag is very strict, otherwise the shelf life of warmer will be very short.
For the plastic packing bag, there are two options—alu foil pack(Alu Plastic bag) and KPET+PE pack in our factory, the difference is that the alu fol bag extra add a layer of aluminum foil between the layers of KPET and PE, the shelf life of KPET+PE bag is 3 years, generally the shelf life of alu foil bag is a little bit longer than the bag PKET+PE, but usually we don’t advise our customer choose the Aluminum Foil plastic packaging, not only the reason that the cost of it is a little bit higher than KPET+PE bag, but also that there is risk to react with the material of alu.
Because the air activated product is different from other product’s, the raw materials of it contains iron powders, which lead to Alu foil packing method has a risk for this product, after several months, the Alu foil packing bag maybe become like a ball, because once the Alu meet the Iron to react, there are some air come, so the product has the risk, and this happened twice before in China local market. Even the risk maybe very low, but we really advise customer don’t choose this packaging method.
To be honest, KPET+PE packing bag is a better choice, the sealing property of it is 8 times than regular packing bag’s, the shelf life is 3 years, and there is no any risk that react with iron powder to swell like a ball.
The bag printing factory we cooperated is the best printing factory in China, all material used are high quality also,and all their goods are for export, their quality is totally different from the small factory’s and we can promise that the shelf life of all our warmers are 3 years.