Color streaking is not completely removed during cosmetic tube extrusion, PlasE clean purging Compound vs Virgin Resin: Which Is More Effective?

Industry Overview

Polyethylene (PE) is the primary material used for cosmetic tube packaging, with common resin grades including 206.48, 2426 and 7042. Production typically relies on single-layer extrusion as well as 4-layer, 5-layer and 7-layer co-extrusion lines for manufacturing facial cleanser tubes, sunscreen tubes, shampoo tubes and other personal care packaging.

As cosmetic brands continue to launch new products and seasonal packaging, manufacturers are required to perform increasingly frequent color changes. Switching between red, white, blue, green and transparent products has become part of daily production, making fast and reliable purging an important factor in overall productivity.

l Small Batch Production & Short Lead Times

Frquent small-batch production requires more color changes. Dry pigments are often used for cost savings but can accumulate in the feed section, increasing purging time and material consumption.

l Difficult Dark-to-Light Color Changes

Switching from red, blue or other dark colors to white, natural or transparent is one of the most challenging color changes. Residual pigments can easily remain inside the extrusion system.

l Dead Spots in the Extrusion System

Low shear force allows resin and pigments to build up in die heads, adapters, flanges and screen pack assemblies. These dead spots are difficult to clean with conventional resin purging.

Customer Case

     Application: 5-Layer Co-Extrusion Cosmetic Tube Production Line

     Equipment Configuration

·      Inner Layer Extruder: PE Φ50

·      Outer Layer Extruder: PE Φ45

     Challenge

  The production line frequently switched from red, magenta and orange to pure white, natural and transparent products, representing one of the most demanding color change applications in the cosmetic tube extrusion industry.

     Previous Cleaning Method

  Virgin PE resin combined with production regrind was used as the conventional purging method.

     Limitations of the Previous Method

•   Purging Time: 180–240 minutes

•   Material Consumption: Approx. 120 kg

•   Previous color occasionally reappeared after production restart

•   Incomplete pigment removal

•   High startup scrap rate

•   Long machine downtime

    PlasE® Purging Procedure & Results

        •    Recommended Grade: PlasE® Clean A 2501

        •    Purging Procedure: Feed PlasE® Clean A 2501 into the extrusion line. Slightly increase the die head temperature, then alternate between extrusion and soak cycles several times. Once the discharged material is visually clean, introduce the production resin to verify the purging performance before resuming normal production.

        •    Purging Time & Material Consumption:   

             Purging Compound Consumption: Approx. 10 kg

             Total Purging Time: 70 minutes

       •   Purging Results    

             Complete removal of previous color contamination    

             No startup scrap caused by residual pigments

Customer Benefits

• Improved Production Efficiency

Significantly reduces both purging time and material consumption, increasing machine utilization and overall production efficiency.

• Thorough Cleaning Performance

Effectively removes accumulated pigments, degraded resin and color contamination, minimizing startup scrap and ensuring a cleaner transition between production runs.

• Equipment Protection

Helps remove residual resin from difficult-to-clean areas throughout the extrusion system, including dead spots, reducing the risk of carbon build-up while protecting screws, barrels and die components.

• Wide Processing Compatibility

Suitable for both single-layer and multi-layer co-extrusion applications.

Environmentally compliant formulations are available. Simply provide the resin type and processing temperature, and the PlasE® technical team can recommend the most suitable grade for your application.

Benefits for the Cosmetic Tube Packaging Industry

•   Higher machine utilization

•   Lower overall operating costs

•   Reduced production waste and startup scrap

•   Lower risk of customer complaints caused by color contamination

•   Improved manufacturing competitiveness

Why Choose PlasE^® Purging Compound?

•   Superior cleaning performance with complete pigment removal

•   Non-abrasive formulation that will not damage screws, barrels or dies

•   Fast transition back to production resin with minimal material loss

•   Environmentally compliant formulations, with selected grades meeting FDA requirements