This invention concerns an isothermal bag keeping the temperature of food and beverages inside even.
People often feel like having cool food or drinks (e.g. water, tea, wine, soft drinks etc) within their reach especially when the weather is hot and no fridge is available, such as when they are on the beach, on a tennis court or during long journeys.
Today there are several systems to keep food and drinks cool without using a fridge, as widely known. These systems include thermoses, portable coolers and thermos flasks, which may however have some minor or major drawbacks for users. Thermoses are usually cumbersome and carrying them causes inconvenience once the drink is finished. Portable coolers (which are made cold by artificial ice) are cumbersome and heavy to carry. Thermos flasks are light but cumbersome, too. Therefore portable coolers and thermos flasks are only used when users carry both drinks and foodstuffs, thus accepting all the inconvenience related to their weight and dimensions. But people often wish to have just one cool drink or some food kept in a small box or bowl (e.g. yoghurt, ice-cream, a sandwich etc.) within their reach, in which case they do not carry anyone of the above-mentioned cooling systems because of their inconveniences. Therefore, food and drinks become warm and unappetising after a short period of time, especially if they are under the sun.
Another solution consists in using specific bags for bottles, such as those described in U.S. Pat. Nos. Des 403,926 and 5,890,809. However, these containers do not cover the bottle completely and reduce heat insulation. U.S. Pat. Nos. Des 409,450 and N. 5,804,265 make reference to some other bags for bottles, which actually do cover bottles completely, but have no hole to drink directly from them. Indeed, users need to open and close the bag every time they want to drink, the which is uncomfortable and increases heat exchange between the inside and the outside. U.S. Pat. No. Des 392,025 gives a rather effective solution because the bag covers the bottle up to its neck, thus enabling users to open the stopper without opening the bag too. Unfortunately though, the bag is closed by a string and is therefore vulnerable to dust, sand and other unhygienic conditions implying higher manufacturing costs.
SUMMARY OF THE INVENTION
This invention aims at providing users with a new a new isothermal bag, which can keep food or drink temperature even and does not have the same inconvenience as the above-mentioned cooling systems.
These goals are achieved by this flexible, isothermal and pocket-size bag. It is made by folding a rectangular foil in two which is then fixed by two sides joined by welding or any other method. The final product is a bag with just one opening on the shorter side. The opening is delimited by two flaps each of which has a hole that is approximately the same size as a bottle neck. The holes are located near the edges of the open shorter side. The edges of each hole may be elasticised or reinforced by welding or rings made up of different materials. The two holes are approximately coaxial.
The bag is approximately the same size as a bottle, so that the bag can perfectly wrap it up.
The foil is made up of three different layers of soft and flexible synthetic materials which are specifically used for foodstuffs. The external layer is reflective, the intermediate one has thermal-insulation characteristics and the internal one is waterproof and/or reflective. The foil may also be made up of four layers, in which case the external layer is reflective, the two intermediate ones have thermal-insulation characteristics, whereas the internal one is waterproof and/or reflective. It is also possible to use a foil with one single layer featuring thermal-insulation, waterproof and reflective characteristics. The isothermal bag may have round corners and its bottom may be folded.
An elastic band, a string or a ribbon may be fixed outside the bag, which may be rolled up or folded up before or after being used so as to become compact and pocket-size. The elastic band, the string or the ribbon keep the bag rolled or folded and prevent it from spreading out again.
An alternative solution is given by another hole on the closed shorter side, which is approximately the same size as a bottle neck, too. As an alternative, the bag may have just one hole on the closed shorter side. In this case, the edges of the shorter side can be provided with a closing device such as a minigrip or a handle.
The bag can also be made by joining two rectangular foils, which are fixed together along three sides, that is the two longer sides and the shorter one. This isothermal bag has many of the advantages offered by other cooling systems but does not have their drawbacks. Indeed, it is handy and very light, it may be used again, it is hard to break, easy to carry and user-friendly. It is a pocket-size bag and can therefore be put away very easily and with very little encumbrance.
Its weight is extremely low as the materials used are very light. However, although the materials are very light they are extremely resistant, so resistant that the bag can be used several times. On the other hand, the bag is very cheap and users can throw it away after using it just one single time.
The holes on the bag may also be used as a handle so that users can easily carry the bottle by holding it with one finger.
Unlike usual thermal bags, this one wraps up bottles completely thus increasing heat insulation. Its holes enable users to drink straight from the bottle without opening and closing the bag every time they want to drink, thus reducing heat exchange between the inside and the outside. Its closing device is easy, functional and hygienic at the same time.
One of the main advantages of this bag lies in its hygienic characteristics. Indeed, it is made up of waterproof materials which are specifically used for food and drinks. Condensation (which is produced when cold bottles get in contact with warm air) is pretty much reduced by this invention, so that the bag can avoid unhygienic mixing between condensation and the materials (such as sand, seaweed, red earth, dust etc.) located on the surface where the bottle is placed. This way, users can avoid dirtying their hands or the container where the isothermal bag is placed, such as handbags, belt bags, rucksacks etc. Moreover, the bag can easily be washed as it is made up of waterproof materials.