Abstract: Unitary measuring pipettes include a tubular body of biaxially oriented thermoplastic material, together with size reduction, elimination, and/or reorientation of longitudinally spaced, raised circumferential witness features, to mitigate or avoid interference between such witness features and graduated volumetric markings on an outside surface of the tubular body. Methods and apparatus for vacuum forming of unitary measuring pipettes are also provided. Gas permeable apertures or pores having a maximum width of no greater than 150 microns, in ranges of 10-100 microns, 10-50 microns, or subranges thereof, may be defined in face plates or inserts received by mold blanks, or defined in molding surface of cooperating mold bodies, and may be used to produce a tubular pipette body having reduced height witness features. Cooperating mold bodies may each be produced from multiple mold body sections with gas passages defined therein and/or therebetween.

Abstract: Unitary measuring pipettes include a tubular body of biaxially oriented thermoplastic material, together with size reduction, elimination, and/or reorientation of longitudinally spaced, raised circumferential witness features, to mitigate or avoid interference between such witness features and graduated volumetric markings on an outside surface of the tubular body. Methods and apparatus for vacuum forming of unitary measuring pipettes are also provided. Gas permeable apertures or pores having a maximum width of no greater than 150 microns, in ranges of 10-100 microns, 10-50 microns, or subranges thereof, may be defined in face plates or inserts received by mold blanks, or defined in molding surface of cooperating mold bodies, and may be used to produce a tubular pipette body having reduced height witness features. Cooperating mold bodies may each be produced from multiple mold body sections with gas passages defined therein and/or therebetween.

Abstract: Measuring pipettes including integral or encapsulated filters, as well as methods and apparatuses for forming the same, are provided. A filter material (e.g., a discrete element in solid form) or a filter material precursor (e.g., a foamable thermoplastic composition and a blowing agent) to be introduced into a hollow interior of a softened thermoplastic material present within a mold during pipette fabrication. A pipette includes a filter element comprising foamed polymeric material within a mouthpiece region, wherein an outer portion of the filter element is bound to or encapsulated in an inner wall of the mouthpiece region. A filter material precursor may be supplied coaxially with a tubular flow of thermoplastic material into the mold, may be supplied laterally through a mold wall, or may be injected into a molten thermoplastic pipette forming material upstream of an extruder outlet.

Abstract: A method for producing pipettes (110, 111, 112) is provided. The method includes extruding a polymer melt into at least one mold segment of a mold assembly (120) having a plurality of mold segments to form a parison (50) or preform, wherein the plurality of mold segments (122) comprise cavities (42) that are shaped to form pipettes when in communication with the cavity of an adjacent mold segment; forming at least two pipettes in the shape of the mold segment cavities by blow-molding or vacuum forming the parison or preform, each of the at least two pipettes having proximal and distal ends; heating the pipettes to form a locally heated portion of the at least two pipettes; and separating the pipettes by cutting the locally heated portion of the at least two pipettes with separation feature (64, 66, 194, 196).

Abstract: An extrusion device is provided. The extrusion device includes an extrusion die having a die bushing comprising a channel extending to an opening of the die bushing, a die pin positioned in the channel, and at least one die pin support feature extending between the die pin and the die bushing.

Abstract: A pipette may comprise a length, a longitudinal axis, and an inner curved surface enclosing a space. The pipette may have a tip region having a tip thickness. The tip region may be connected to a body region having a body thickness. The tip thickness may be greater than the body thickness. The body region may be connected to a mouth region having a mouth thickness. The mouth thickness may be greater than the body thickness. The inner curved surface may not contain bumps or ridges either between the tip region and the body region or between the body region and the mouth region. The pipette may be formed by blow molding or vacuum forming.

Abstract: A serological pipette has an elongated hollow tubular body having an optical transmission of 40 to 70% over a range of 390 to 700 nm. The pipette body is formed from a polymer composition that includes 5 to 30 wt. % poly(styrene-butadiene-styrene) and 70 to 95 wt. % polystyrene. The tubular body is formed by extrusion at a barrel temperature ranging from 400 to 500 F.

Abstract: A stretch blow molding method may include fabricating a preform (e.g., by molding, optionally while a core pin rotates within a mold cavity), heating the preform to a softening temperature, stretching and thereby elongating at least a portion of the heated preform, blowing the elongated preform with pressurized fluid within a mold cavity, and cooling the resulting pipette. A system for fabricating a stretch blow molded pipette includes a first mold defining a mold cavity for producing a preform. A stretch rod drive unit is configured to move a stretch rod within an interior of the preform to form an elongated preform, and a second mold defines blow molding cavity and a molding surface to contain expansion of the elongated perform when subjected to blowing by supplying pressurized fluid to an interior thereof.

Abstract: Measuring pipettes including integral or encapsulated filters, as well as methods and apparatuses for forming the same, are provided. A filter material (e.g., a discrete element in solid form) or a filter material precursor (e.g., a foamable thermoplastic composition and a blowing agent) to be introduced into a hollow interior of a softened thermoplastic material present within a mold during pipette fabrication. A pipette includes a filter element comprising foamed polymeric material within a mouthpiece region, wherein an outer portion of the filter element is bound to or encapsulated in an inner wall of the mouthpiece region. A filter material precursor may be supplied coaxially with a tubular flow of thermoplastic material into the mold, may be supplied laterally through a mold wall, or may be injected into a molten thermoplastic pipette forming material upstream of an extruder outlet.

Abstract: Unitary measuring pipettes include a tubular body of biaxially oriented thermoplastic material, together with size reduction, elimination, and/or reorientation of longitudinally spaced, raised circumferential witness features, to mitigate or avoid interference between such witness features and graduated volumetric markings on an outside surface of the tubular body. Methods and apparatus for vacuum forming of unitary measuring pipettes are also provided. Gas permeable apertures or pores having a maximum width of no greater than 150 microns, in ranges of 10-100 microns, 10-50 microns, or subranges thereof, may be defined in face plates or inserts received by mold blanks, or defined in molding surface of cooperating mold bodies, and may be used to produce a tubular pipette body having reduced height witness features. Cooperating mold bodies may each be produced from multiple mold body sections with gas passages defined therein and/or therebetween.

Abstract: A method for producing pipettes (110, 111, 112) is provided. The method includes extruding a polymer melt into at least one mold segment of a mold assembly (120) having a plurality of mold segments to form a parison (50) or preform, wherein the plurality of mold segments (122) comprise cavities (42) that are shaped to form pipettes when in communication with the cavity of an adjacent mold segment; forming at least two pipettes in the shape of the mold segment cavities by blow-molding or vacuum forming the parison or preform, each of the at least two pipettes having proximal and distal ends; heating the pipettes to form a locally heated portion of the at least two pipettes; and separating the pipettes by cutting the locally heated portion of the at least two pipettes with separation feature (64, 66, 194, 196).

Abstract: A pipette may comprise a length, a longitudinal axis, and an inner curved surface enclosing a space. The pipette may have a tip region having a tip thickness. The tip region may be connected to a body region having a body thickness. The tip thickness may be greater than the body thickness. The body region may be connected to a mouth region having a mouth thickness. The mouth thickness may be greater than the body thickness. The inner curved surface may not contain bumps or ridges either between the tip region and the body region or between the body region and the mouth region. The pipette may be formed by blow molding or vacuum forming.

Abstract: A pipette may comprise a length, a longitudinal axis, and an inner curved surface enclosing a space. The pipette may have a tip region having a tip thickness. The tip region may be connected to a body region having a body thickness. The tip thickness may be greater than the body thickness. The body region may be connected to a mouth region having a mouth thickness. The mouth thickness may be greater than the body thickness. The inner curved surface may not contain bumps or ridges either between the tip region and the body region or between the body region and the mouth region. The pipette may be formed by blow molding or vacuum forming.

Abstract: A serological pipette has an elongated hollow tubular body having an optical transmission of 40 to 70% over a range of 390 to 700 nm. The pipette body is formed from a polymer composition that includes 5 to 30 wt. % poly(styrene-butadiene-styrene) and 70 to 95 wt. % polystyrene. The tubular body is formed by extrusion at a barrel temperature ranging from 400 to 500F.