High Specific-heat Capacity Materials
Heating packs can also be made by filling a container with a material that has a high specific heat capacity, which then gradually releases the heat over time. A hot water bottle is the most familiar example of this type of heating pad.
A microwavable heating pad is a heating pad that is warmed by placing it in a microwave oven before use. Microwavable heating pads are typically made out of a thick insulative fabric such as flannel and filled with grains such as wheat, buckwheat or flax seed. Due to their relative simplicity to make, they are frequently sewn by hand, often with a custom shape to fit the intended area of use. In rare instances, these types of pads have been known to ignite during or after the microwave process and cause fires.
Often, aromatic compounds will also be added to the filler mixture to create a pleasant or soothing smell when heated. The source of these can vary significantly, ranging from adding essential oils to ground up spices such as cloves and nutmeg, or even dried rose petals.
Read more about this topic: Heating Pad
Famous quotes containing the words high, capacity and/or materials:
“Gifts of one loved me,—
‘T was high time they came;
When he ceased to love me,
Time they stopped for shame.”
—Ralph Waldo Emerson (1803–1882)
“People between twenty and forty are not sympathetic. The child has the capacity to do but it can’t know. It only knows when it is no longer able to do—after forty. Between twenty and forty the will of the child to do gets stronger, more dangerous, but it has not begun to learn to know yet. Since his capacity to do is forced into channels of evil through environment and pressures, man is strong before he is moral. The world’s anguish is caused by people between twenty and forty.”
—William Faulkner (1897–1962)
“Herein is the explanation of the analogies, which exist in all the arts. They are the re-appearance of one mind, working in many materials to many temporary ends. Raphael paints wisdom, Handel sings it, Phidias carves it, Shakspeare writes it, Wren builds it, Columbus sails it, Luther preaches it, Washington arms it, Watt mechanizes it. Painting was called “silent poetry,” and poetry “speaking painting.” The laws of each art are convertible into the laws of every other.”
—Ralph Waldo Emerson (1803–1882)