Garbage Bags & Can Liners Explained
Choosing the right can liner material saves money and prevents messy failures. This guide explains the three main polyethylene types used in trash bags, how thickness is measured, and which liner works best for each application.
The Three Can Liner Materials
LDPE — Low-Density Polyethylene
LDPE is the original plastic bag material — the soft, stretchy film you recognize from sandwich bags. LDPE can liners are generally thicker and more flexible than other types, with excellent puncture resistance. They conform to the shape of the can and resist tears from sharp or irregular objects. Most LDPE liners are made from recycled plastic. Because of their thickness, LDPE liners are the best choice for heavy-duty applications — construction debris, industrial waste, and sharp or heavy loads.
LLDPE — Linear Low-Density Polyethylene
LLDPE liners combine good tensile strength with puncture resistance. They stretch under load without tearing, making them ideal for heavy or oddly-shaped waste. LLDPE is thicker than HDPE but thinner than LDPE, offering a balance of strength and economy. These liners are the workhorse choice for offices, restaurants, and institutional settings where loads are mixed and unpredictable.
HDPE — High-Density Polyethylene
HDPE liners are thin with a frosted, crinkly appearance. Despite being the thinnest option, they have excellent tensile strength — they can hold heavy loads without stretching. However, HDPE is more easily punctured by sharp objects. HDPE liners are measured in microns rather than mils. They are the most economical choice for high-volume, lightweight waste — paper, packaging, and office trash.
Material Comparison
| Property | LDPE | LLDPE | HDPE |
|---|---|---|---|
| Appearance | Clear, glossy | Clear to translucent | Frosted, crinkly |
| Thickness | Thickest (0.6–6 mil) | Medium (0.4–1.5 mil) | Thinnest (6–22 mic) |
| Measurement | Mils | Mils | Microns |
| Puncture Resistance | Excellent | Good | Low |
| Tensile Strength | Moderate | Good | Excellent |
| Stretch | High | High | Low |
| Best For | Heavy/sharp waste, industrial | Mixed loads, institutional | Lightweight, high-volume |
Mil vs. Micron: Understanding Thickness
Mil (1/1000 of an inch) is used for LDPE and LLDPE liners. A higher mil number means a thicker, stronger bag. Common ratings range from 0.4 mil (light duty) to 6 mil (extra heavy duty).
Micron (1/1000 of a millimeter) is used for HDPE liners. Common ratings range from 6 microns (economy) to 22 microns (premium). You cannot directly compare mil to micron ratings across materials — a 6-micron HDPE bag and a 0.6-mil LDPE bag are very different products.
Seal Types
Star seal (most common): The bottom is gathered and sealed in a star pattern, eliminating channels where liquid can leak. Star seal bags fit most round and square cans.
Flat seal (heat seal): A straight seal across the bottom. Simpler construction, typically used in flat-packed case liners.
Gusseted seal: Side gussets allow the bag to expand and conform to the can shape, maximizing capacity in square or rectangular containers.