The Role of Box Liners in Industrial Packaging

Role of Box Liners:

In the world of industrial packaging, protecting contents from moisture, dust, or contamination is a constant challenge. One of the simplest but most effective solutions is the poly box liner — a loose-fitting LDPE bag that lines the inside of a box to protect contents during storage or shipment. 

What Are Box Liners?

Box liners are made from polyethylene and designed to fit inside standard cartons or custom-sized boxes. At M Plastics Inc., we produce these liners using our in-house blown film extrusion lines. The liners are then cut to size and packaged flat or on rolls for easy use. 

They can be made in layflat or gusseted form depending on the dimensions and contents of the box. Gusseted liners are useful for wider bases, while layflat options work best for uniformly sized products.

How They're Used

Box liners are especially popular in industrial, food service, and medical industries. They're often used for: 

• Lining gaylords and bulk containers 

• Protecting metal parts from moisture 

• Separating food ingredients from cardboard 

• Preventing powder or small particles from leaking 

• Handling product returns or recycled material 

At M Plastics, all of our liners are custom-made to match your box sizes and load weights. We only use virgin or in-house reprocessed LDPE, never post-consumer waste, to ensure film consistency and cleanliness. 

Options Available

Our liners come with optional printing, color tinting (for batch identification), and can be made from standard or VCI-treated LDPE film if metal protection is needed. 

Clients can request light, medium, or heavy gauges depending on the use case. Minimum order quantities and lead times apply, which vary based on width and film thickness.

Why It Matters: 

For operations handling heavy or delicate parts, skipping a liner can lead to contamination or corrosion — risking the integrity of your product. Box liners serve as a critical first layer of protection in your packaging system. 

Contact our team to explore liner options that align with your load sizes, stacking strength, and packing flow.