Is the double-layered glass water cup a thermos cup

Many merchants selling glass water cups will name their double-layered glasswater cups as so-and-so double-layered glass thermos cups, and some will even indicate that the insulation time can reach more than 4 hours.

So is the double-layered glass water cup a thermos cup?

According to the international industry's definition of a thermos cup, a double-layer glass water cup is not a thermos cup, it is not a thermos cup, it is not a thermos cup. Important questions have been mentioned three times. As for being able to keep warm for more than 4 hours, it depends on how the other party changes the concept. If it is said that temperatures above zero are considered hot, then there seems to be no problem with what the other party said. The international industry defines a thermos cup, which requires that hot water at 96 degrees Celsius be poured into the cup, and it should be opened 6-8 hours after sealing. A qualified thermos cup must be maintained at 55 degrees Celsius.

How is the insulation effect?

After you understand this concept, you might as well take the double-layered glass water cup you have on hand to do a test, and also pour in freshly boiled water (depending on the altitude, the temperature of freshly boiled water is mostly between 96℃-98℃). After sealing the lid, observe whether the double-layer glass water cup can meet the standard within the internationally defined time. The answer must be impossible. The editor can responsibly say that even if boiling water is poured into the double-layer glass water cup, it will basically pass through After about 2 hours, the temperature in the water cup will be around 55℃. This is still tested under the natural temperature of 25℃. If the natural temperature is low in winter, the temperature in the water cup will be around 2 hours. It is a natural temperature, not to mention heat preservation, not to mention that it can have a heat preservation effect of more than 4 hours.

Some merchants are not convinced and say that the 4 hours of heat preservation and low temperature we mentioned. Okay, let's do another test. Pour half room temperature water and half ice cubes into the double-layer glass. Basically, the water glass obtained will be maintained at about zero degrees Celsius. After 10 minutes, you will find that water condensation beads will appear on the outer wall of the glass water glass. This This means that this water cup must not be insulated. The surface of the insulated water cup will not form condensation beads because the temperature inside the cup is below zero degrees Celsius. Of course, if you want to insist that the water in the cup is cold in winter, then it must be the same temperature after 4 hours. If the outdoor temperature is lower, the water in the cup will be even lower.