Abstract: Use of an electrically charged nonwoven fabric that is made of a fiber predominantly composed of an amorphous polymer provides a novel filtration material having improved performance compared to that of conventional filtration materials, and having excellent heat resistance and excellent flame retardancy as well as an electrically charged nonwoven fabric for use in the filtration material. It is preferable that the surface charge density is greater than or equal to 1×10?10 coulomb/cm2. It is preferable that the collection efficiency for collecting a dust particle with a particle diameter of 1 ?m flowing at a fabric-passing velocity of 8.6 cm/second is greater than or equal to 40%, the QF value is greater than or equal to 0.05, and the decrement of the dust-particle collection efficiency after being allowed to leave at 100° C. for 24 hours is less than or equal to 10%.

Abstract: A nonwoven fabric including fibers that contain a polymer having a glass transition temperature of greater than or equal to 50° C. as a main component, and having a vertical strength of greater than or equal to 1 N/5 cm per 1 g/m2, and by satisfying both of the following conditions (1) and (2), a nonwoven fabric having sufficient strength to be handled alone and including fibers that contain a polymer having a Tg of greater than or equal to 50° C. as a main component without performing a post processing such as emboss processing, calender processing, or spunlace processing, and a method for producing the nonwoven fabric can be provided. (1) A density is 0.01 to 0.4 g/cm3. (2) A proportion of parts with a density exceeding 0.4 g/cm3 is less than or equal to 3% in a cross section in a thickness direction.

Abstract: Use of an electrically charged nonwoven fabric that is made of a fiber predominantly composed of an amorphous polymer provides a novel filtration material having improved performance compared to that of conventional filtration materials, and having excellent heat resistance and excellent flame retardancy as well as an electrically charged nonwoven fabric for use in the filtration material. It is preferable that the surface charge density is greater than or equal to 1×10?10 coulomb/cm2. It is preferable that the collection efficiency for collecting a dust particle with a particle diameter of 1 ?m flowing at a fabric-passing velocity of 8.6 cm/second is greater than or equal to 40%, the QF value is greater than or equal to 0.05, and the decrement of the dust-particle collection efficiency after being allowed to leave at 100° C. for 24 hours is less than or equal to 10%.

Abstract: A laminated sheet is produced by forming an adhesion layer permeable to a liquid component and contactable with a skin on at least one side of a liquid-retention layer comprising a nonwoven structural member and having an ability to absorb the liquid component. The adhesion layer comprises a nonwoven structural member comprising a fiber having a number-average fiber diameter of not more than 10 ?m, and the thickness ratio of the adhesion layer relative to the liquid-retention layer is 1/4 to 1/100 as a ratio of the adhesion layer/the liquid-retention layer. The fiber of the nonwoven structural member of the adhesion layer may have a standard deviation of fiber diameter of not more than 5. The nonwoven structural member of the liquid-retention layer may comprise a fiber having a fiber diameter larger than that of the fiber of the adhesion layer.

Abstract: A laminated sheet is produced by forming an adhesion layer permeable to a liquid component and contactable with a skin on at least one side of a liquid-retention layer comprising a nonwoven structural member and having an ability to absorb the liquid component. The adhesion layer comprises a nonwoven structural member comprising a fiber having a number-average fiber diameter of not more than 10 ?m, and the thickness ratio of the adhesion layer relative to the liquid-retention layer is 1/4 to 1/100 as a ratio of the adhesion layer/the liquid-retention layer. The fiber of the nonwoven structural member of the adhesion layer may have a standard deviation of fiber diameter of not more than 5. The nonwoven structural member of the liquid-retention layer may comprise a fiber having a fiber diameter larger than that of the fiber of the adhesion layer.