[PROCESS INFO] Our expert talks about Blown Film Extrusion

Because the support of our partners is a key step for the integration of our technology, our R&D team uses all its know-how to insert Lactips innovation throughout the product value chain with the aim of supporting the transformation of the plastic industry in an efficient and eco-responsible way.

Experienced in the various plastic technical transformations, Kheirdine Mellouki, our plastics process expert, presents the transformation process by blown film extrusion:

What is blown film extrusion?

Blown film extrusion is a method of processing plastic raw materials. Pellets material is heated inside a sheath and pushed by an extrusion screw through an annular die with air injected into the centre to shape a bubble. The resulting sheath can be rolled up for bagging applications or split to produce films for packaging applications for example.

How Lactips material is transformed by the blown film extrusion process?

Blown film extrusion is the most widely used transformation process since the creation of Lactips. First tested in the laboratory of the Jean Monnet University and then developed in our development workshop, the CareTips® material, a real breakthrough innovation, is transformed into film to meet numerous historical applications such as single-dose water-soluble packaging for dishwasher tabs or even more recent applications such as the manufacture of water-soluble ties for anti-contamination laundry bags for example.

The CareTips® range includes specific products for processing by blown film extrusion: CareTips® 300 and CareTips® 310. Lactips has also developed the ProcessTips range which is a processing aid grade in the CareTips® matrix to facilitate processing.

While CareTips® is compatible with blown film extrusion machines, it is necessary to take into account its unique characteristics. For example, a low process temperature is required. A temperature profile with a conventional ramp up is recommended. The process temperatures depend on the type of machine and its size.

A high screw rotation is necessary for the processing of our material in order to limit its residence time in the extruder while having a good material work, trying however to limit self-heating. As CareTips® material is rheofluidic, it is also important to have sufficient filtration to allow the establishment of a high back pressure which is essential for good material processing.

The winding tensions must be adjusted to ensure a good winding of the reels. All parts from the extrusion screw outlet to the die must be chrome or nickel plated.

Because the needs of our partners are unique, our process support team assists them in the realisation of their specifications and answers their problems thanks to our innovative, natural and customisable material.

What are the applications?

Because plastic raw materials are necessary for human activity, but controlling their end-of-life is essential, Lactips has formed a partnership with Plastiques Venthenat, a French industrial company that has been specialising in the blown film extrusion of highly technical plastic films for over 40 years.

To further strengthen and extend its dedicated range of plastics for water-soluble packaging, Plastiques Venthenat transforms CareTips® pellets, into rolls of films, marketed under the BIOCYTER® brand. Plastiques Venthenat is directly addressing the single-dose monolayer packaging and detergent markets and laundry services, particularly in the medical sector (thanks to the applications for water-soluble ties and bags).