To protect dry food from deterioration by oxidation and to obtain a wrapping material for dry food which can store it stably over a long period by providing a hydrophilic layer and an oxygen absorbing layer containing an oxygen absorbing agent and a deliquescent substance.
A film 1 of a layer containing an oxygen absorbing agent and a deliquscent substance, a film 2 of a hydrophilic layer, a water permeable film 3 which is stuck to the lower layer of the film 1, for example, a polyethylene film which gives a heat sealing property to a composite sheet material. Besides, aluminum foil which gives oxygen-water barrier properties to the entire composite sheet material which is stuck to the upper side of the film 1 is formed The layer 2 the water content of which is adjusted and the layer 1 adjoin through the film 3. Water from the layer 2 passes through the film 3 and migrates to the layer 1.
SUGIYAMA YASUO
HARANO SHIGENOBU