A production method for a low molecular weight polymer suitable for a melt-blown non-woven fabric and a production device for melt-blown non-woven fabric, with which a high molecular weight polymer can be reduced in molecular weight by applying a shear force to the high molecular weight polymer without adding an additive. The low molecular weight polymer and the melt-blown non-woven fabric are produced using a continuous high shearing device that applies a shear force to the high molecular weight polymer serving as a raw material by rotation of a screw body to reduce the molecular weight of the high molecular weight polymer so as to obtain a low molecular weight polymer, and cools the low molecular weight polymer by passing the low molecular weight polymer through a passage arranged in the axial direction inside the screw body.

A production method for a low molecular weight polymer suitable for a melt-blown non-woven fabric and a production device for melt-blown non-woven fabric, with which a high molecular weight polymer can be reduced in molecular weight by applying a shear force to the high molecular weight polymer without adding an additive. The low molecular weight polymer and the melt-blown non-woven fabric are produced using a continuous high shearing device that applies a shear force to the high molecular weight polymer serving as a raw material by rotation of a screw body to reduce the molecular weight of the high molecular weight polymer so as to obtain a low molecular weight polymer, and cools the low molecular weight polymer by passing the low molecular weight polymer through a passage arranged in the axial direction inside the screw body.

Absorbent product including a laminate of at least two plies, wherein the absorbent product has a measured Valley Volume parameter greater than 11 microns and a Pit Density of greater than 25 pockets per sq. cm.

Absorbent product including a laminate of at least two plies, wherein the absorbent product has a measured Valley Volume parameter greater than 11 microns and a Pit Density of greater than 25 pockets per sq. cm.

Systems, devices and methods are provided for producing fibrous materials and products, such as filters. A system comprises a first device for generating one or more fiber stream(s), and a second device for isolating nanoparticles within a gaseous medium. The second device forms the nanoparticles into a stream and feeds this stream into the fiber streams to form the fibrous material. This distributes the nanoparticles more uniformly throughout the fibrous material. In addition, the nanoparticles increase the overall surface area within the material, which, in certain applications, increases its filtration efficiency and allows for the capture of submicron contaminants without significantly compromising other factors, such as pressure drop through the filter. Filters produced with these systems and methods are capable of withstanding rigorous conditioning, which allows the filter to achieve substantially the same level of filtration performance throughout the lifetime of the filter.

Systems, devices and methods are provided for producing fibrous materials and products, such as filters. A system comprises a first device for generating one or more fiber stream(s), and a second device for isolating nanoparticles within a gaseous medium. The second device forms the nanoparticles into a stream and feeds this stream into the fiber streams to form the fibrous material. This distributes the nanoparticles more uniformly throughout the fibrous material. In addition, the nanoparticles increase the overall surface area within the material, which, in certain applications, increases its filtration efficiency and allows for the capture of submicron contaminants without significantly compromising other factors, such as pressure drop through the filter. Filters produced with these systems and methods are capable of withstanding rigorous conditioning, which allows the filter to achieve substantially the same level of filtration performance throughout the lifetime of the filter.

Filter media and filters, such as air filters, face masks, gas turbine and compressor air intake filters, panel filters and the like, are provided that include high linear density fibers and nanoparticles dispersed throughout at least a portion of the filter media. A filter includes a filter media comprising a substrate of fibers having a linear density of greater than about 3 denier, and nanoparticles disposed within the substrate. The larger linear density fibers provide more open space or pores within the filter media, allowing for a greater density of nanoparticles to be dispersed therein. This improves the overall efficiency of the filter. The three-dimensional distribution of nanoparticles within the filter also provides resistance against complete blockage of a particular portion of the filter, thereby reducing the overall pressure drop across the filter.

Filter media and filters, such as air filters, face masks, gas turbine and compressor air intake filters, panel filters and the like, are provided that include high linear density fibers and nanoparticles dispersed throughout at least a portion of the filter media. A filter includes a filter media comprising a substrate of fibers having a linear density of greater than about 3 denier, and nanoparticles disposed within the substrate. The larger linear density fibers provide more open space or pores within the filter media, allowing for a greater density of nanoparticles to be dispersed therein. This improves the overall efficiency of the filter. The three-dimensional distribution of nanoparticles within the filter also provides resistance against complete blockage of a particular portion of the filter, thereby reducing the overall pressure drop across the filter.

Electret webs include a thermoplastic resin and a charge-enhancing additive. The charge-enhancing additive is a substituted-benzoic acid or a substituted-benzoate salt. The benzoic acid and benzoate salts are substituted by a hydroxyl or amino group at the ortho position or 1 position of the benzene ring. The benzene ring may contain additional substituent groups. The substituted-benzoate salt may have a monovalent, divalent, or trivalent metal counteraction.

Electret webs include a thermoplastic resin and a charge-enhancing additive. The charge-enhancing additive is a substituted-benzoic acid or a substituted-benzoate salt. The benzoic acid and benzoate salts are substituted by a hydroxyl or amino group at the ortho position or 1 position of the benzene ring. The benzene ring may contain additional substituent groups. The substituted-benzoate salt may have a monovalent, divalent, or trivalent metal counteraction.