A thermal bag is a type of thermally
insulated shipping container in the form of a bag which can be carried, usually made of
thermally insulating materials and sometimes a refrigerant
gel
A gel is a semi-solid that can have properties ranging from soft and weak to hard and tough. Gels are defined as a substantially dilute cross-linked system, which exhibits no flow when in the steady-state, although the liquid phase may still di ...
. It is used to help maintain the temperature of its contents, keeping cold items cold, and hot items hot.
Insulated bags have been in use for many years in industry, medical/pharmaceutical use,
food delivery
Retail food delivery is a courier service in which a restaurant, store, or independent food-delivery company delivers food to a customer. An order is typically made either through a restaurant or grocer's website or mobile app, or through a food ...
,
lunch bags, etc. Several designs have been available.
Shopping bags
Commercial thermal shopping bags, to carry temperature-sensitive purchases home without breaking the
cold chain, were first introduced by grocery and other shops in Europe in the mid 1980s. A thermal bag to keep pizzas being delivered hot was invented by
Ingrid Kosar in 1983, and is commonly used now.
A
cool box
A cooler, portable ice chest, ice box, cool box, chilly bin (in New Zealand), or esky (Australia) is an insulated box used to keep food or drink cool.
Ice cubes are most commonly placed in it to help the contents inside stay cool. Ice packs ar ...
is very similar in concept, but typically larger and in the form of a rigid box.
Medical use
Thermal pharmaceutical bags are designed to transport temperature-sensitive medications, protecting them from damaging temperatures, shocks, and light. Many vaccines are delicate biological substances that can lose part or all of their effectiveness if they are frozen, allowed to get too hot, or exposed to bright light. Such vaccines must be kept within a specified temperature range, typically , from manufacture to use. According to the
World Health Organization
The World Health Organization (WHO) is a specialized agency of the United Nations responsible for international public health. The WHO Constitution states its main objective as "the attainment by all peoples of the highest possible level of h ...
, at least 7% of temperature-sensitive medical products suffer significant degradation in potency in transit.
Materials
Thermal bags are usually manufactured with varying quantities of the following materials:
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PET film (biaxially oriented) (Mylar, etc.)
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Styrofoam
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Fabric
Textile is an umbrella term that includes various fiber-based materials, including fibers, yarns, filaments, threads, different fabric types, etc. At first, the word "textiles" only referred to woven fabrics. However, weaving is not the ...
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Nonwovens
Nonwoven fabric is a fabric-like material made from staple fibre (short) and long fibres (continuous long), bonded together by chemical, mechanical, heat or solvent treatment. The term is used in the textile manufacturing industry to denote fabri ...
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Polyethylene
Polyethylene or polythene (abbreviated PE; IUPAC name polyethene or poly(methylene)) is the most commonly produced plastic. It is a polymer, primarily used for packaging ( plastic bags, plastic films, geomembranes and containers including bo ...
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Polyurethane
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Polypropylene
Polypropylene (PP), also known as polypropene, is a thermoplastic polymer used in a wide variety of applications. It is produced via chain-growth polymerization from the monomer propylene.
Polypropylene
belongs to the group of polyolefins and ...
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gel packs
See also
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Food safety
Food safety (or food hygiene) is used as a scientific method/discipline describing handling, preparation, and storage of food in ways that prevent food-borne illness. The occurrence of two or more cases of a similar illness resulting from t ...
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HACCP
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Heat transfer
Heat transfer is a discipline of thermal engineering that concerns the generation, use, conversion, and exchange of thermal energy (heat) between physical systems. Heat transfer is classified into various mechanisms, such as thermal conduction, ...
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Packaging
Packaging is the science, art and technology of enclosing or protecting products for distribution, storage, sale, and use. Packaging also refers to the process of designing, evaluating, and producing packages. Packaging can be described as a co ...
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Temperature control
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Insulated shipping container
References
{{DEFAULTSORT:Thermal Bag
Food storage containers
Food preservation
Packaging
Temperature control
Shipping containers
Bags