Provided is a microporous film which has a surface A and a surface B opposite to the surface A. In one embodiment, the microporous film has a ratio (F.sub.B/F.sub.A) of a dynamic friction coefficient F.sub.B of the surface B to a dynamic friction coefficient F.sub.A of the surface A of 1.2 to 20. In another embodiment, the microporous film is a single layer having a thickness of 3-18 μm, a number N.sub.A of pores on the surface A is 10-100/μm.sup.2, a number N.sub.B of pores on the surface B is 20-200/μm.sup.2, and N.sub.A/N.sub.B is 0.2-0.96. In addition, a total area S.sub.A of pores on the surface A is 0.02-0.5 μm.sup.2/μm.sup.2, a total area S.sub.B of pores on the surface B is 0.01-0.3 μm.sup.2/μm.sup.2, and S.sub.A/S.sub.B is 1.1-10. Furthermore, in another embodiment, a number W.sub.B of protrusion-like bodies on the surface B is 0.2-1000/100 μm.sup.2.

A method of extruding filament comprises the steps of cutting a bulk source material into pieces having size S.sub.1, performing a first extrusion pass comprising the steps of melting the pieces in an extruding device at a temperature T.sub.1 and extruding a first filament at an extrusion speed V.sub.1, and performing at least one additional extrusion pass k comprising the steps of cutting the first filament into pieces having size S.sub.k, melting the pieces in an extruding device at temperature T.sub.k, and extruding a final filament at an extrusion speed V.sub.k. A system for extruding filament is also described.

A process and related assembly for creating an extrusion molded article with a chemically applied outer film. An extruded base material is formed during a first extrusion operation, following which a multi-layer film is bonded to the base material while the base material still at an above ambient temperature. The multi-layer film further includes successive layers of each of a polypropylene (PP), an adhesive, a polyethylene terephthalate (PET), a coating and s subsequent surface PET. The step of bonding of the film further occurs during an intermediate step between the first extrusion operation for forming the base material according to a given profile section and a subsequent extrusion operation for applying additional material along an edge of the film, the additional material including profile wings as required for a given design.

The current three-dimensional object manufacturing technique relies on the deposition of a pseudoplastic flame retardant material in gel aggregate state. The gel flows through a deposition nozzle because the applied agitation and pressure shears the bonds and induces a breakdown in the material elasticity. The elasticity recovers immediately after leaving the nozzle, and the gel solidifies to maintain its shape and strength.

A process produces an electrical line which extends in the longitudinal direction and the line has a line core and an outer shell. In a continuous shaping process, individual shell portions of the outer shell are formed successively by surrounding the line core with a curable plastic substance. In at least one portion, the outer shell is produced having a cross-sectional geometry which can be varied in the longitudinal direction of the line.

Foam slabs and methods and apparatus, including foaming dies, for making and using foam slabs.

An apparatus for extruding a jacket and/or insulative material onto an extruded product with one or more longitudinal stripes incorporated onto the surface of said extruded product comprising a body, a primary feed conduit for conveying a primary extrusion material, a striping die, a secondary feed conduit for conveying a secondary extrusion material, a striping die adapter, a striping feed conduit extending through the striping die adapter for conveying striping extrusion material. The striping die adapter may also include a thermocouple for maintaining the viscosity of the striping extrusion material and a thermocouple for monitoring the temperature of said striping die adapter. The striping die includes one or more striping extrusion outlets for conveying striping extrusion material onto the extruded product. The striping die may also include a wishbone-shaped trough for delivering equal amounts of striping extrusion material to said extrusion outlets for extrusion onto the product.

A die for a polymer mixing machine includes first and second opposing surfaces. Each defines first cylindrical portions and second V-shaped portions interspaced between each first portion. The first and second opposing surfaces produce a ply with first portions thicker than second portions and throated portions therebetween.

Implementations described herein are directed to forming objects including one or more layers of a polymeric material that include a magnetic material. The objects can be produced by forming one or more first layers that include a first polymeric material. The one or more first layers can be free of a magnetic material. Additionally, the object can be produced by forming one or more second layers that include a second polymeric material having a magnetic material. For example, the one or more second layers can include a polymeric material embedded with magnetic particles. The one or more first layers and the one or more second layers can be formed by extruding the first polymeric material and the second polymeric material onto a substrate according to a pattern. A magnetizing device can be used to magnetize the magnetic material included in the one or more second layers.

Mold blocks of a pipe molding corrugator are provided with enhanced cooling capability due to the provision of cooling fins on the side portions of each mold block. Air can be forced between the fins and some exhaustion of the air can occur at the base of the fins adjacent the mold block cavity. With this arrangement, enhanced cooling of mold blocks is possible.