PURPOSE: To reduce the degree of water absorption for a foam material and to obtain therewith a water-stopping material for loose clearance that is excellent in water-stopping capacity by a method wherein the outer layer of the end on the upper side of the foam material having continuous bubbles is impregnated with water-repellent.
CONSTITUTION: The outer layer 3 of the end on the upper side 2 of a foam material having continuous bubbles 1 is impregnated with water-repellent. As occasion demands, the sides 7 are impregnated with the water-repellent. In other words, the material is made to be impermeable to water by presence of the water-repellent. On the other hand, the bubbles 1 on the end of the underside 4 are made to communicate with the outside air. In other words, the outside air can be taken easily into the foam material 1 through the end on the underside 4. Even though water gathers over a water-stopping material, a great amount of air can be taken into the foam material through the end on the underside 4. Thereby, the degree of water absorption by the foam material can be reduced, improving water-stopping capacity.
KASHIWABARA MASAHIKO
NITTA KK