Water absorbent material, dehumidification device, and dehumidification method

1. A moisture absorbing material (i) having (a) a first state in which the moisture absorbing material is capable of absorbing moisture, and (b) a second state in which the moisture absorbing material releases the moisture absorbed in the first state, and (ii) having a property of changing from the first state to the second state in response to an external stimulus and returning from the second state to the first state when the external stimulus disappears, the moisture absorbing material comprising:

first through Nth moisture absorbing bodies (where N is an integer of not less than 2) which have respective different stimulus response levels and are provided in order of stimulus response level so as to be in contact with one another, wherein

two adjacent moisture absorbing bodies among the first through Nth moisture absorbing bodies are configured such that, in response to the external stimulus which exceeds a stimulus response level of a first one of the two adjacent moisture absorbing bodies and which does not exceed a stimulus response level of a second one of the two adjacent moisture absorbing bodies, letting moisture absorbed by the first one of the two adjacent moisture absorbing bodies move to the second one of the two adjacent moisture absorbing bodies, so that an amount of moisture in the second one of the two adjacent moisture absorbing bodies increases.

2. The moisture absorbing material as set forth in claim 1 , wherein the external stimulus causes the first through Nth moisture absorbing bodies (N is an integer of not less than 2) to exhibit, in accordance with the respective stimulus response levels, hydrophilicity as the first state and hydrophobicity as the second state.

3. The moisture absorbing material as set forth in claim 1 , wherein:

the external stimulus is heat;

the first through Nth moisture absorbing bodies (N is an integer of not less than 2) have respective different temperature sensitive points, each of which is a stimulus response level; and

the first through Nth moisture absorbing bodies (N is an integer of not less than 2) each exhibit (i) hydrophilicity as the first state in a temperature range not higher than a corresponding temperature sensitive point and (ii) hydrophobicity as the second state in a temperature range higher than the corresponding temperature sensitive point.

4. The moisture absorbing material as set forth in claim 2 , wherein any two adjacent moisture absorbing bodies of the first through Nth moisture absorbing bodies (N is an integer of not less than 2) are provided so as to be in contact with each other in a side-by-side state or in a stacked state.

5. A dehumidifying device comprising:

a moisture absorbing material (i) having (a) a first state in which the moisture absorbing material is capable of absorbing moisture, and (b) a second state in which the moisture absorbing material releases the moisture absorbed in the first state, and (ii) having a property of changing from the first state to the second state in response to an external stimulus and returning from the second state to the first state when the external stimulus disappears, the moisture absorbing material including:

first through Nth moisture absorbing bodies (where N is an integer of not less than 2) which have respective different stimulus response levels and are provided in order of stimulus response level so as to be in contact with one another, wherein the external stimulus causes the first through Nth moisture absorbing bodies to exhibit, in accordance with the respective stimulus response levels, hydrophilicity as the first state and hydrophobicity as the second state;

a heater that heats the first through Nth moisture absorbing bodies; and

control circuitry that subjects the first through Nth moisture absorbing bodies, each having absorbed moisture, to control of heating by the heater so that the first through Nth moisture absorbing bodies each have a temperature in a range higher than a corresponding temperature sensitive point of each of the first through Nth moisture absorbing bodies.

6. The dehumidifying device as set forth in claim 5 , wherein:

the heater includes first through Nth heating bodies corresponding to heating of the respective first through Nth moisture absorbing bodies; and

the control circuitry subjects the first through Nth moisture absorbing bodies, each having absorbed moisture, to individual control of heating by the first through Nth heating bodies so that the first through Nth moisture absorbing bodies each have a temperature in a range higher than a corresponding temperature sensitive point of each of the first through Nth moisture absorbing bodies.

7. A dehumidifying method using a moisture absorbing material (i) having (a) a first state in which the moisture absorbing material is capable of absorbing moisture and (b) a second state in which the moisture absorbing material releases the moisture absorbed in the first state and (ii) having a property of changing from the first state to the second state in response to an external stimulus and returning from the second state to the first state when the external stimulus disappears, the dehumidifying method comprising:

providing first through Nth moisture absorbing bodies (where N is an integer of not less than 2) in order of stimulus response level so that the first through Nth moisture absorbing bodies are in contact with one another, the first through Nth moisture absorbing bodies having respective different stimulus response levels; and

providing each of the first through Nth moisture absorbing bodies, each having absorbed moisture, with a stimulus whose level is higher than a corresponding stimulus response level of each of the first through Nth moisture absorbing bodies, wherein

two adjacent moisture absorbing bodies among the first through Nth moisture absorbing bodies, in response to the external stimulus which exceeds a stimulus response level of a first one of the two adjacent moisture absorbing bodies and which does not exceed a stimulus response level of a second one of the two adjacent moisture absorbing bodies, letting moisture absorbed by the first one of the two adjacent moisture absorbing bodies move to the second one of the two adjacent moisture absorbing bodies, so that an amount of moisture in the second one of the two adjacent moisture absorbing bodies increases.