Abstract: A method of modifying a polymeric material whereby the polymeric material is modified to give a highly durable surface without decreasing its strength. Namely, a polymeric material is modified by the method comprising a combination of an impregnation step, an activation step, a step of grafting a monomer and a step of a treatment with a hydrophilic polymer. Thus, the hydrophilic nature, adhesiveness, and so forth of polymeric materials such as polyolefins can be improved without causing any decrease in the practical strength. The thus obtained polymeric materials are usable in articles with a need for high water absorptivity and high adhesiveness, for example, water-absorbing materials and water-retaining materials for medical, sanitary, cosmetic articles or supplies, agricultural materials, synthetic papers, filters and fiber products for clothes, for improving adhesiveness of composite materials and the like.

Abstract: The present invention relates to a vacuum filter bag comprising a layer containing immobilized odor-retaining particles characterized in that the abrasion loss of said odor-retaining particles caused by an air flow of 90 cm/s through a 200 cm2 specimen of said layer for two hours, measured in accordance with DIN 44956 T2, is 0 to 10% by weight of the total odor-retaining particles present before starting the air flow. The vacuum filter bags of the invention have a high dust holding capacity and an excellent long lasting odor removing effect.

Abstract: The invention relates to a dust filter bag having a highly porous backing material ply and to a method for producing the dust filter bag

Abstract: A dust filter bag constituted of a plurality of layers including at least one carrier material and at least one non-woven tissue layer wherein the at least one non-woven tissue layer has a nano non-woven tissue with an average fiber diameter of 10 to 1000 mm, a basis weight of 0.05 to 2 g/m2 and an air permeability of 1500 to 20,000 l/m2×s, and the at least one carrier material layer and an air permeability of more than 70 l/m2×s, and a breaking resistance in the longitudinal direction of more than 20 N/15 mm strip width, and in the transverse direction of more than 10 N/15 mm strip width. The dust filter bag is suitable for use in vacuum cleaners for the efficient reduction of the finest dust, without the suction power of the vacuum cleaner being notably reduced.

Abstract: A dual- or multi-layer filter medium for air filtration, having at least one meltblown layer (2, 2a and 5) at least one meltblown layer (2 and 2a) is placed on the inlet side of the filter medium. The meltblown layer has a pore size larger than that of the next following layer or layers.