Packaging Pitfalls: Top 3 Watchouts for PE, PET, and PP Bottles with Scott Roman

PET, PE, and PP bottles are among the most widely used plastic packaging options in beauty and personal care, appreciated for their durability, flexibility, lightweight convenience, and cost effectiveness. However, these materials can present challenges to brand owners and packaging engineers such as overflow capacity, decoration integrity, and material compatibility. Below, I outline the top three pitfalls associated with PET, PE, and PP bottles, the potential impact on your brand, and best practices to avoid them.

Starting a new project? Schedule a meeting with a Packaging Pro to avoid common packaging pitfalls for your component types.

1. Insufficient Overflow Capacity (OFC)

Commonly overlooked overflow capacity is crucial as an undersized bottle can significantly disrupt your product labeling, causing regulatory issues and consumer disappointment.

Implications

Misleading label claims may lead to regulatory penalties.
Consumer dissatisfaction due to perceived underfilling of the product.

How to Avoid: Start with the OFC indicated on your bottle’s technical drawing, then deduct:

Plastic bottle tolerance
Volume displacement from internal components (e.g., pump, dropper, wiper, rod & applicator, orifice reducer plug)
Required headspace
Filling equipment tolerance

The resulting volume after these deductions gives your accurate legal label claim in milliliters or fluid ounces. If claiming by weight, convert this calculated volume into grams or ounces using your product’s specific gravity.

2. Decoration Adhesion or Compatibility Failures

Decoration is a critical piece of brand differentiation, but poor adhesion or compatibility issues can rapidly degrade the visual quality of your finished PET, PE, or PP bottles.

Implications

Adhesion failures lead to decoration peeling or wearing off without direct product contact.
Compatibility failures occur when chemical interactions between the product and decoration materials degrade appearance and functionality.

How to Avoid: Ensure rigorous testing of decorated components, including spray coatings, hot-stamping, silk-screening, heat-transfer labels, and pad-printing, for both adhesion and chemical compatibility with your product. Adjustments may involve modifying curing properties, dwell times, inks or lacquers' chemical compositions, selecting alternative foils, or adding a UV-cured clear topcoat to isolate and protect the decoration from the formula.

3. Material Incompatibility with Product

Choosing incompatible materials can result in significant issues like product migration through bottle walls or surface deformation known as “paneling.”

Implications

Product leakage, weight loss, or compromised formulation stability due to ingredient migration.
Bottle deformation or collapse, causing aesthetic and functional failure.

How to Avoid: Conduct a material science analysis to predict potential interactions between your product's formula ingredients and the bottle’s resin. Identify materials resistant to migration and paneling issues. Always confirm findings through comprehensive package compatibility testing to ensure bottle integrity throughout your product's intended shelf life.

By proactively considering and addressing overflow capacity, decoration integrity, and material compatibility, you will be well on your way to safeguard the quality and reliability of your products packaged in PET, PE, and PP bottles

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About the Author

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Scott is an award-winning package development professional with 30+ years of multi-industry experience. A seasoned packaging expert with extensive experience in beauty and cosmetics, Scott led packaging innovation for the makeup category at Estée Lauder, driving projects from concept to launch in lip, foundation, primer, and makeup / skincare hybrid packaging. Before that, he directed package development for Tom Ford Beauty, overseeing luxury packaging in fragrance, makeup, and skincare. With expertise spanning all cosmetic packaging materials and processes, Scott has a strong background in project management, packaging development, and on-site production across global facilities.