text: Hitherto, it has been known a disposable body warmer of the type wherein an exothermic composition which generates heat in the presence of air is accommodated within an air-permeable bag (inner bag) and this inner bag is enveloped with an air-impermeable bag (outer bag).
  Body warmers of such type include, as well as one for warming limbs and waist portions, a thin and small-sized one which has been proposed for warming of the sole of a foot.
  However, where such a conventional body warmer adapted to warm the sole of a foot is used in a shoe, there arises a problem that it tends to slip in the shoe and hence cannot warm a desired portion accurately.
  To solve this problem, there is proposed a body warmer of the type in which its inner bag is provided with an adhesive layer on one side thereof and which is adapted to be stuck to a desired portion of the sole of a foot with an intervening sock or stocking, or to be stuck directly to the sole of a shoe.
  This type of body warmer, however, has problems that it is difficult for the warmer to be disposed in position for use and to be released after use and that socks or stockings or the soles of shoes are likely to be soiled because of the adhesive remaining on the portion from which the body warmer has been released.
  There are additional problems that in the course of determining a location to which the body warmer is to be stuck in a shoe by groping, the body warmer might be stuck to an undesired portion, and that the adhesive layer might be stuck to the sole of a shoe too tightly because of the weight of user applied on his or her foot and, hence, the base fabric of the shoe would be damaged when the body warmer is released therefrom after use.
  In view of the foregoing circumstances, it is an object of the present invention to provide a body warmer which is prevented from slipping in footwear and is capable of warming a desired portion accurately.