Filter pack and air filter provided with same

A filter pack comprising:

• a filter medium collecting fine particles in a gas and the filter medium comprising folds alternately repeated on an upstream side and on a downstream side of airflow by a pleating process, at least one pair of upstream ventilation surfaces which face each other via the fold on the downstream side therebetween and into which the airflow flows, and at least one pair of downstream ventilation surfaces which face each other via the fold on the upstream side therebetween and from which the airflow flows out;
• a plurality of space maintaining members formed on each of the upstream ventilation surfaces and each of the downstream ventilation surfaces to maintain spaces of each pair of upstream ventilation surfaces and each pair of downstream ventilation surfaces, wherein
• the plurality of space maintaining members formed on each of the upstream ventilation surfaces are intermittently formed to be spaced apart from each other in a direction orthogonal to the fold on the downstream side, thereby defining a successive spacing on each of the upstream ventilation surfaces in the direction orthogonal to the fold on the downstream side,
• wherein the successive spacing is defined by exposed surface regions of each of the upstream ventilation surfaces;
• and
• at least one of the space maintaining members formed on one side of the pair of upstream ventilation surfaces is in contact at two or more places with at least one of the space maintaining members formed on the other side of the pair of upstream ventilation surfaces.