An extruding unit, a forming roll unit and a thick portion forming mechanism are provided. The extruding unit has an ejecting slit which ejects sheet-shaped molten resin. The ejecting slit includes a standard gap portion and an enlarged gap portion. The standard gap portion is formed as a gap having a constant size. The enlarged gap portion is formed as a gap larger than the standard gap portion in a position corresponding to a thick portion. The thick portion forming mechanism forms one or several thick portions which are thicker than other portion, in the sheet-shaped molten resin continuously in the extrusion direction.

An extruding unit, a forming roll unit and a thick portion forming mechanism are provided. The extruding unit has an ejecting slit which ejects sheet-shaped molten resin. The ejecting slit includes a standard gap portion and an enlarged gap portion. The standard gap portion is formed as a gap having a constant size. The enlarged gap portion is formed as a gap larger than the standard gap portion in a position corresponding to a thick portion. The thick portion forming mechanism forms one or several thick portions which are thicker than other portion, in the sheet-shaped molten resin continuously in the extrusion direction.

A calender for the treatment of web-like materials, including a fixed structure adapted to support two heated rollers shaped to be connected to the fixed structure, to a drive unit and to a heating system. The calender includes automatic elements for engaging and respectively for disengaging the rollers to and from the fixed structure, the drive unit and the heating system; the automatic elements are controlled by a programmable control unit and each of the rollers has an engaging surface shaped to be engaged by mechanical elements for moving the rollers which move the rollers between the calender and one or more waiting or parking stations while the rollers are at a temperature between 50° C. and 200° C.

An extruding unit, a forming roll unit and a thick portion forming mechanism are provided. The extruding unit has an ejecting slit which ejects sheet-shaped molten resin. The ejecting slit includes a standard gap portion and an enlarged gap portion. The standard gap portion is formed as a gap having a constant size. The enlarged gap portion is formed as a gap larger than the standard gap portion in a position corresponding to a thick portion. The thick portion forming mechanism forms one or several thick portions which are thicker than other portion, in the sheet-shaped molten resin continuously in the extrusion direction.

Calender for the treatment of web-like materials, including a fixed structure supporting two heated rollers reciprocally arranged so as to form a nip traversable by web-like materials, where each roller has pins mounted on bearings. The structure includes two lower levers and two upper levers adapted for exerting on the bearings forces oriented according to not coinciding directions, each lever being connected with an actuator that controls its rotation around a horizontal axis to put it in a first engagement position of the respective bearing and in a second release position, such that in the second position of the levers the extraction of the rollers from the calender is allowed.

A composite shaping apparatus includes at least one first roller that loads a prepreg with pressure, at least one second roller that loads the prepreg with pressure, and at least one motor that rotates at least one of the first roller or the second roller. The at least one first roller and the at least one second roller are rotated while at least one of rotation speed, roller diameter, or presence/absence of rotating power is made different between at least one of the first roller and at least one of the second roller.

A composite shaping apparatus includes at least one first roller that loads a prepreg with pressure, at least one second roller that loads the prepreg with pressure, and at least one motor that rotates at least one of the first roller or the second roller. The at least one first roller and the at least one second roller are rotated while at least one of rotation speed, roller diameter, or presence/absence of rotating power is made different between at least one of the first roller and at least one of the second roller.

A calender for the treatment of web-like materials, including a fixed structure adapted to support two heated rollers shaped to be connected to the fixed structure, to a drive unit and to a heating system. The calender includes automatic elements for engaging and respectively for disengaging the rollers to and from the fixed structure, the drive unit and the heating system; the automatic elements are controlled by a programmable control unit and each of the rollers has an engaging surface shaped to be engaged by mechanical elements for moving the rollers which move the rollers between the calender and one or more waiting or parking stations while the rollers are at a temperature between 50? C. and 200? C.

The manufacturing device is provided with a first roller and a second roller for molding an uneven-thickness film. The first roller is provided with a truncated-cone-shaped portion and a disc-shaped portion, the diameter of the disc-shaped portion is larger than the diameter of a large-diameter face of the truncated-cone-shaped portion, and the second roller is provided with a column-shaped portion. A thick part is formed in a molded body of the uneven-thickness film between the truncated-cone-shaped portion of the first roller and the column-shaped portion of the second roller, and a thin connecting part is formed in the molded body between the disc-shaped portion of the first roller and the column-shaped portion of the second roller.

The invention relates to a process to make films and tapes from ultrahigh molecular weight polyethylene (UHMWPE) in the solid state. The films and tapes according to the invention have an improved thickness whereby the coefficient of variation of the thickness of the film of at most 6%.