What is the shrink rate of PETG shrink film?

PETG shrink film—made from Polyethylene Terephthalate Glycol-modified resin—is a high-performance heat shrink material widely used for shrink sleeve labels, full-body packaging, and tamper-evident wraps. One of its defining characteristics is its shrink behavior when exposed to heat in a shrink tunnel or heat tunnel. 

Typical Shrinkage Performance

When heated, PETG shrink film contracts, pulling tightly around a container or product surface. The shrink rate is primarily measured in two directions relative to how the film was oriented during manufacturing:

1. Transverse Direction (TD):

This is the across-film direction, and PETG exhibits significantly high shrinkage here.

Typical TD shrink rates range from approximately 60% to 80%, with many commercial grades engineered to achieve 75% or higher.

2. Machine Direction (MD):

Shrinkage in the machine (lengthwise) direction is usually much lower, often less than 5% or near zero, designed to minimize distortion such as the “smile effect” on bottle tops and bottoms.

How Shrink Rates Vary by Film Grade

PETG shrink films are formulated for different shrink profiles classified as:

● Medium Shrink Grades: ~40–55% TD shrink, used where dramatic contouring is not required.

● Standard/High Shrink Grades: ~70–80% TD shrink, ideal for highly contoured bottles, jars, and irregular containers.

Practical Implications of Shrink Rate

Tight Conformability:

High TD shrink rates (typically 70–80%) allow PETG film to wrap tightly around complex shapes such as tapered bottles, square containers, or curved products. This not only improves visual appeal but also enhances protection and label adhesion.

Controlled Dimensional Stability:

Low MD shrink contributes to dimensional stability during thermoforming, reducing unwanted distortion and enabling more predictable shrink tunnel calibration.

Shrink Temperature:

While shrink rate values are driven by orientation and resin formulation, PETG films typically begin to shrink at 70–80°C (158–176°F) and reach full shrink near 90–95°C (194–203°F) in standard industrial conditions. 

Why Shrink Rate Matters in Packaging

Brand Presentation:

A higher shrink rate ensures a snug fit, eliminating wrinkles or loose areas that can degrade the package’s visual quality.

Performance on Irregular Shapes:

Complex container geometries benefit from films that can shrink over 60–80% in TD to conform without tearing.

Print Finish Optimization:

Controlled shrink prevents graphic distortion, crucial for 360° shrink sleeve labels with detailed artwork.

Summary of Typical PETG Film Shrink Rates

PETG shrink film is valued for its high transverse shrink rate (often 70–80%) and low machine-direction shrink, enabling superior fit and appearance for a wide range of packaging applications. Understanding these shrink profiles enables manufacturers to choose the right grade for their product shapes, shrink tunnel settings, and visual requirements.