A defibration unit includes a rotating unit and a fixing unit. The rotating unit and the fixing unit are arranged so as to be apart from each other with a gap therebetween in a direction that intersects with a rotating shaft of the rotating unit. The fixing unit includes a plurality of plates that are layered in an axial direction of the rotating shaft, and the plates has a plurality of convexities that protrude at a side facing the rotating unit.

A defibrating unit includes a rotating unit and a fixing unit. The rotating unit and the fixing unit are arranged so as to be apart from each other with a gap therebetween in an intersecting direction that intersects with a rotating shaft of the rotating unit. The rotating unit includes a surface that stands up along an axial direction of the rotating shaft and that is arranged on a side section in the axial direction and arranged at a side where a defibration object is introduced. The fixing unit includes a plurality of plates that are layered in the axial direction, and the plates has a plurality of convexities that protrude at a side facing the rotating unit.

The invention relates to heat treatment of polymorphic semicrystalline or crystallizable polymers to increase the content of the highest melting crystalline form. Such heat treatment results in a polymer powder that has a consistent, uniform melting range, improved flow and improved durability of the powder particle size for applications that require powder flow at elevated temperatures. In addition to improved powder properties, the articles produced from the powders also exhibit better physical properties in both appearance and in mechanical properties. Thus the invention also includes polymer powders and articles produced by the described processes.

The invention relates to heat treatment of polymorphic semicrystalline or crystallizable polymers to increase the content of the highest melting crystalline form. Such heat treatment results in a polymer powder that has a consistent, uniform melting range, improved flow and improved durability of the powder particle size for applications that require powder flow at elevated temperatures. In addition to improved powder properties, the articles produced from the powders also exhibit better physical properties in both appearance and in mechanical properties. Thus the invention also includes polymer powders and articles produced by the described processes.

A device for filtering a plastic melt, including a housing and a filter pin which is axially and/or radially movable therein. In a working position of the filter pin, plastic melt passes from an inlet channel, through a filtering mechanism, which is detachably fastened to the filter pin, to an outlet channel. In a filter change position of the filter pin, the filtering mechanism is freely accessible for replacing the filtering mechanism, and wherein at least one drainage channel is formed in the filter pin. In a start-up position of the filter pin, one end of the at least one drainage channel is in fluid connection with the at least one inlet channel in order to receive the plastic melt that is fed through the at least one inlet channel and to output the plastic melt at another end of the at least one drainage channel.

A sheet manufacturing apparatus includes a defibrating unit and a sheet forming unit. The defibrating unit includes a rotating unit and a housing, and is configured to carry out a dry-type defibrating process by rotating the rotating unit. The housing includes a cover portion and a fixing unit attached to the cover portion and spaced apart from the rotating unit in a direction perpendicular to an axial direction of the rotating unit so as to form a gap between the rotating unit and the fixing unit. The sheet forming unit is configured to form a sheet by accumulating defibrated material. The rotating unit includes a rotor having protruding sections on an outer circumference of the rotor, and a feeding blade arranged on a side section of the rotor on a side of an input section for the defibration object and configured to generate a flow of air.

A sheet manufacturing apparatus includes a defibrating unit and a sheet forming unit. The defibrating unit includes a rotating unit and a housing, and is configured to carry out a dry-type defibrating process by rotating the rotating unit. The housing includes a cover portion and a fixing unit attached to the cover portion and spaced apart from the rotating unit in a direction perpendicular to an axial direction of the rotating unit so as to form a gap between the rotating unit and the fixing unit. The sheet forming unit is configured to form a sheet by accumulating defibrated material. The rotating unit includes a rotor having protruding sections on an outer circumference of the rotor, and a feeding blade arranged on a side section of the rotor on a side of an input section for the defibration object and configured to generate a flow of air.

A sheet manufacturing apparatus includes a defibration unit and a sheet forming unit. The defibration unit includes a rotating unit and a housing including a cover portion and a fixing unit attached to the cover portion and spaced apart from the rotating unit in a direction perpendicular to an axial direction of the rotating unit so as to form a gap between the rotating unit and the fixing unit. The defibrating unit is configured to cause the rotating unit to rotate and dry-defibrate a defibration object. The sheet forming unit is configured to form a sheet by depositing defibrated material. The rotating unit includes rotating plates base sections located on a side of a central rotation axis and protruding sections protruding out in a direction drawing away from the central rotation axis, and the rotating plates is stacked such that the protruding sections are in contact in the axial direction.

A sheet manufacturing apparatus includes a defibration unit and a sheet forming unit. The defibration unit includes a rotating unit and a housing including a cover portion and a fixing unit attached to the cover portion and spaced apart from the rotating unit in a direction perpendicular to an axial direction of the rotating unit so as to form a gap between the rotating unit and the fixing unit. The defibrating unit is configured to cause the rotating unit to rotate and dry-defibrate a defibration object. The sheet forming unit is configured to form a sheet by depositing defibrated material. The rotating unit includes rotating plates base sections located on a side of a central rotation axis and protruding sections protruding out in a direction drawing away from the central rotation axis, and the rotating plates is stacked such that the protruding sections are in contact in the axial direction.

The present disclosure relates to a polyethylene composition with improved swell ratio and mechanical properties for use in preparing blow-moulded articles and having the following features: 1) a density from 0.945 to less than 0.952 g/cm.sup.3; 2) an MIF/MIP ratio from 15 to 30; 3) a Shear-Induced Crystallization Index (SIC) from 2.5 to 5.5.