What is a co extruded film?
Coextruded multi-layer film is produced by a compound molding technique that simultaneously extrudes thermoplastic resin with multiple extruders and passes that through a single die to build up layers of melted resin both on the inside and outside of a film.
How does extrusion lamination work?
Extrusion lamination brings two films together using a layer of molten resin extruded through computer-controlled extruder dies with advanced gauge controls (nuclear gauge monitoring and automatic profile control). The two films and the molten resin form a multilayer flexible packaging lamination.
What is extrusion lamination machine?
Tandem Lamination Plant For coating Circular Woven fabric, for producing multilayer laminates up to 5 layers along with the various substrates like Paper, Aluminum foil, Polyester film etc. …
What is co-extrusion packaging?
Co-extrusion is defined by the number of plastic substances or polymers used in the extrusion process. The substances are heated separately and then joined together before being molded into the proper shape.
What is adhesive lamination process?
Laminating is the process through which two or more flexible packaging webs are joined together using a bonding agent. In general terms an adhesive is applied to the less absorbent substrate web, after which the second web is pressed against it to produce a duplex, or two-layer, laminate.
What is the meaning of extrusion coating?
Extrusion coating is the coating of a molten web of synthetic resin onto a substrate material. It is a versatile coating technique used for the economic application of various plastics, notably polyethylene, onto paperboard, corrugated fiberboard, paper, aluminium foils, cellulose, Non-wovens, or plastic films.
What are types of extrusions?
Types of Extrusion Process
- Direct Extrusion.
- Indirect Extrusion.
- Hydrostatic Extrusion.
- Lateral or Vertical Extrusion.
- Hot extrusion.
- Cold Extrusion.
- Impact Extrusion.
How does the extrusion coating process take place?
The actual process of extrusion coating involves extruding resin from a slot die at temperatures up to 320°C directly onto the moving web which may then passed through a nip consisting of a rubber covered pressure roller and a chrome plated cooling roll. The latter cools the molten film back into the solid state and also imparts…
How did the process of coextrusion come about?
Coextrusion is the process of forming an extrudate composed of more than one thermoplastic melt stream. The process came about because some service demands, particularly from the packaging industry, could not be satisfied by a single polymer although they could be met by a combination of polymers.
What kind of dies are used for extrusion coating?
Adjustable-while-running deckles are most common and edge bead reduction techniques can be incorporated. Push-pull die bolts usually are necessary since temperatures are high, viscosities low, and internal pressures low. Multimanifold dies for coextrusion are more commonly used in extrusion coating as well as automatic profile control.
How many layers can coextrusion be used for?
Seven or more layers are not uncommon. However, side-by-side coextrusion is also possible. This process is used to produce decorative film and is also employed in profile extrusion, for example to provide a flexible seal along the edge of a rigid strip.