Um......your question is worded oddly, but the way an thermos is insulated is by having a vacuum between it's two flasks. The vacuum causes heat transfer to reduce greatly.
Thermos is a trade name for an insulated food and beverage container
The spelling is "thermos" (still a trademark name Thermos), a vacuum-insulated flask.
thermos/insulated travel mug
There are many brands of insulated tumblers. Thermos is popular for their products as are the Contigo brand. Both brands have various sizes and colors.
Stainless steel is a popular material for thermos flasks because it is durable, has good insulating properties, and is easy to clean. Vacuum-insulated stainless steel thermos flasks can keep liquids hot or cold for long periods of time.
Actually i dont know ,i am here just like u, to find an answer of this question but thank me that i questioned this question firstlY.
Thermos
An insulated thermos containing hot coffee is a good example of an isolated system. The thermos prevents heat transfer with the surroundings, keeping the coffee hot for a longer period.
The Thermos vacuum bottle model no 2460S quart size was likely manufactured in the mid-20th century, around the 1950s-1970s. This model was produced by the Thermos division of King-Seeley Corporation, a prominent manufacturer of insulated food and beverage containers during that time period.
To make a heat thermos, you will need a vacuum-insulated container, usually made of stainless steel, with a tight-fitting lid to trap heat inside. The vacuum insulation prevents heat transfer through conduction, convection, and radiation, keeping liquids hot for hours. Simply pour your hot beverage into the thermos and seal it tightly to maintain its temperature.
white or silver metallic. a vacuum insulated thermos mug will do even better, the the outside color doesn't matter.
Vacuum insulated stainless steel bottles like one from Hydro Flask [see related link "hydro flask" below] or Thermos [see related link "thermos" below] will keep them coldest.