A method for producing a microporous material comprising the steps of: providing an ultrahigh molecular weight polyethylene (UHMWPE); providing a filler, providing a processing plasticizer, adding the filler to the UHMWPE in a mixture being in the range of from about 1:9 to about 15:1 filler to UHMWPE by weight; adding the processing plasticizer to the mixture; extruding the mixture to form a sheet from the mixture; calendering the sheet; extracting the processing plasticizer from the sheet to produce a matrix comprising UHMWPE and the filler distributed throughout the matrix; stretching the microporous material in at least one direction to a stretch ratio of at least about 1.5 to produce a stretched microporous matrix; and subsequently calendering the stretched microporous matrix to produce a microporous material which exhibits improved physical and dimensional stability properties over the stretched microporous matrix.

A thermoplastic bag may include a sidewall that may have a plurality of first and second ribs formed therein. The first ribs may be longer in length but shorter in height than the second ribs. The second ribs may be arranged in discrete networks that appear superimposed over the first ribs. The second ribs may normally remain in a bent-over configuration. When a force is applied, the second ribs may expand the area of the sidewall so that the bag may easily accommodate large objects. To produce the bag, a thermoplastic web may be directed between opposing first and second rollers. One of the rollers may include ridges that may have first and second segments of differing heights that correspond to the differing heights of the first and second ribs. The formation of the first ribs may increase the width of the web.

A thermoplastic bag may include a sidewall that may have a plurality of first and second ribs formed therein. The first ribs may be longer in length but shorter in height than the second ribs. The second ribs may be arranged in discrete networks that appear superimposed over the first ribs. The second ribs may normally remain in a bent-over configuration. When a force is applied, the second ribs may expand the area of the sidewall so that the bag may easily accommodate large objects. To produce the bag, a thermoplastic web may be directed between opposing first and second rollers. One of the rollers may include ridges that may have first and second segments of differing heights that correspond to the differing heights of the first and second ribs. The formation of the first ribs may increase the width of the web.

The invention relates to a process for producing a filled film web from a microporous starting film web of thermoplastic polymer material, which comprises at least one low-melting polymer component, one high-melting polymer component and a filler, the process comprising the following steps: heating of the microporous starting film web to a partly molten state in which at least one low-melting polymer component exists in a molten liquid state and at least one high-melting polymer component does not exist in the molten liquid state, and cooling down by passing the partly molten film web through a cooled roller nip. The invention further relates to the film web produced with the process as well as its use.

The invention relates to a process for producing a filled film web from a microporous starting film web of thermoplastic polymer material, which comprises at least one low-melting polymer component, one high-melting polymer component and a filler, the process comprising the following steps: heating of the microporous starting film web to a partly molten state in which at least one low-melting polymer component exists in a molten liquid state and at least one high-melting polymer component does not exist in the molten liquid state, and cooling down by passing the partly molten film web through a cooled roller nip. The invention further relates to the film web produced with the process as well as its use.

A biaxially oriented polyester film according to the present invention is a biaxially oriented polyester film comprising inorganic particles and a polyester resin, wherein the hardness of a roll obtained by slitting a master roll on which the biaxially oriented polyester film is wound and then by being rewound thereon at a winding tension of 6.5 kg/m to 8.5 kg/m, a winding surface pressure of 35 kg/m to 50 kg/m and a winding rate of 300 m/min to 350 m/min, is 90 to 95 points. The biaxially oriented polyester film prevents the roll from forming wrinkles over time in a roll wound state, and therefore when used as an interlayer of a secondary battery separator, can prevent wrinkles from transferring onto the separator.

An apparatus for fabricating a reinforced stretch film comprising a plurality of edge folding stations, each folding stations being configured to fold each edge of the stretch film one time, a plurality of drums for stretching the stretch film downstream of the plurality of edge folding stations, the drums being configured to rotate with different surface speeds to pre-stretch the stretch film, a final roller for winding the pre-stretched stretch film, and an assembly for driving the final roller.

An apparatus for fabricating a reinforced stretch film comprising a plurality of edge folding stations, each folding stations being configured to fold each edge of the stretch film one time, a plurality of drums for stretching the stretch film downstream of the plurality of edge folding stations, the drums being configured to rotate with different surface speeds to pre-stretch the stretch film, a final roller for winding the pre-stretched stretch film, and an assembly for driving the final roller.

The invention relates to a process for producing a multi-layered film web from at least two starting film webs of thermoplastic polymer material, each starting film web comprising at least one low-melting polymer component and at least one high-melting polymer component. The method comprises the following steps: producing the at least two starting film webs by blown film extrusion, cast extrusion or a combination of blown film extrusion and cast extrusion; passing the at least two starting film webs up to their partly molten state, in which in each starting film web, the at least one low-melting polymer component exists in the molten liquid state, and the at least one high-melting polymer component does not exist in the molten liquid state, together over at least one heating roller, and passing the multi-layered, partly molten film web through a cooled roller nip. The invention further relates to the multi-layered film web produced with the process as well as its use.