The types of lunch bags
The core tasks of lunch bags are "heat preservation, portability and easy cleaning". According to the differences in structure and function, the products on the market can be classified into four major types: "soft-shell insulated bags, hard-shell insulated boxes, folding ice packs, and electric lunch bags". Only by understanding its working principle and applicable scenarios can we choose the right one and use it with peace of mind.
1. Soft-shell insulated bags
The inner wall is made of aluminum foil composite pearl cotton, and the outer layer is mostly Oxford cloth, with a thickness of about 6mm. By reflecting thermal radiation and using the insulation layer to slow down temperature loss, a 60℃ hot soup can remain above 45℃ after 3 hours. Weighing 200g, it can be folded and stuffed into a handbag, making it suitable for office workers with a commuting radius of no more than 10km.
2. Hard-shell insulated box
The PP plastic shell is filled with polyurethane foam, and a silicone rubber sealing ring is set at the cover opening to form an air heat insulation layer. The cavity is 0.8L, the drop resistance height is 1m, and the heat preservation duration is 4 hours. The box body can be washed as a whole without any odor residue. It is often used by students or for car travel. The disadvantage is that it has a fixed volume and takes up a lot of space inside the bag.
3. Fold the ice pack
It is equipped with a high-molecular ice crystal plate. After pre-freezing for 2 hours, the phase change temperature is 0℃, and the bag can maintain a cooling capacity of 8℃ or below for about 5 hours. Summer fresh-keeping salads and dairy products are especially practical. The folding thickness is only 15mm. After thawing, the ice board can be reused over a hundred times, which is economical and environmentally friendly.
4. Electric Heating Lunch Bags
The bottom is embedded with a 20W carbon fiber heating film. It can be powered by a car cigarette lighter or USB-C, and the food can be heated to 75℃ in 30 minutes. It is equipped with a constant temperature setting of 65℃ to prevent the bottom from burning due to overheating. Suitable for long-distance drivers or outdoor camping, but requires a continuous power supply. In environments without a car charger, a mobile power bank should be provided.
The four types of lunch bags each have their own focuses: soft-shell ones are light, hard-shell ones are stable, ice packs keep warm, and electric ones heat up quickly. First, assess the commuting distance, food type and power supply conditions, and then select the corresponding model. This way, lunch can reach the table at the appropriate temperature, reserving a warm energy for the afternoon work.
