A Bopp Jumbo Roll is a large, master roll of Biaxially Oriented
Polypropylene (BOPP) film. It is the primary form in which BOPP film is produced and sold by
manufacturers to converters. These rolls are "jumbo" because they are enormous in both width
(can be over 4 meters / 13 feet) and length (can be tens of
kilometers long). Converters then use slitting and rewinding machines to cut these
jumbo rolls down into smaller, customer-specific rolls for use in
various packaging and printing industries.
Standard Specifications of a Jumbo Roll
When ordering, buyers specify these key parameters:
1.Film Type: This is the most variable specification. Common types include:
2.Plain/Standard: Clear, transparent film.
3.Metallized: Vacuum-coated with a thin layer of aluminum for a
shiny, metallic appearance and enhanced gas barrier.
4.White Opaque: Contains pigments (like titanium dioxide) for a
solid white background, often used for labels.
5.Pearlescent: Has a pearl-like shimmer effect for premium
packaging.
6.Matte: Non-glossy, elegant finish.
7.Coated: e.g., Heat-sealable coating (for sealing bags),
Acrylic-coated (for better ink adhesion), PVDC-coated (for oxygen
barrier).
8.Thickness (Gauge): Measured in microns (μm) or gauges (where 1
gauge = 0.01μm). Common ranges are from 15 to 50 μm.
9.Width: The roll's width, which is the dimension that will be slit
into smaller widths. Can range from 1 meter to over 4 meters.
10.Length: The total length of the film on the roll, typically
measured in meters.
11.Core Inner Diameter (ID): The size of the cardboard core the
film is wound on. Standard sizes are 3" (76mm), 6" (152mm), or
custom sizes to fit the converter's machinery.
12.Outer Diameter (OD): The full diameter of the finished jumbo
roll, which is limited by the handling capacity of the production
and converting equipment.
Manufacturing Process (Simplified)
1.Extrusion: Polypropylene pellets are melted and extruded through
a flat die to form a thin sheet of cast film.
2.Orientation (Stretching): This is the critical "BO" step. The cast film is stretched:
3.Lengthwise (Machine Direction - MD) over a series of heated
rollers.
4.Widthwise (Transverse Direction - TD) in a heated oven called a
tenter frame.
5.This biaxial stretching aligns the polymer molecules, giving the
film its signature strength and stability.
6.Treatment & Coating: The film may undergo a corona treatment to
increase surface energy for printing. It may also receive functional coatings (e.g., for sealing or
barrier properties).
7.Winding: The finished film is wound onto a large cardboard core
at high speed, creating the massive Bopp Jumbo Roll.
