Polyester vs polypropylene for labels: when the difference matters
These are the two most widely used synthetics in industrial labelling and, under most standard conditions, they perform in practically identical fashion. The real difference appears once the environment turns demanding: temperature above 80 °C on a continuous basis, contact with solvents or aggressive chemicals, or durability requirements of several years. In those cases the choice matters. The cards below summarise when.
Choose polyester if…
There are solvents, oils or temperatures >80 °C continuously • Continuous abrasion or friction • You need it to last more than 3 years • Metal parts or machinery
Choose polypropylene if…
The environment is damp or there's water • It goes on packaging or flexible surfaces • Cold chain • Cost per label matters
The difference is irrelevant if…
Dry warehouse at room temperature • No chemical contact • Short-duration use • In that case, choose on price
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Section 1
Key properties of each material
Both materials are synthetic and waterproof. They print by thermal transfer; polypropylene also accepts direct thermal printing. The properties below determine the point at which the demands of the environment make one outperform the other.
Polyester (PET)
The benchmark material for harsh industrial environments
Temperature resistance
Up to 150 °C continuous
With suitable adhesives it withstands prolonged thermal cycling without deforming or losing adhesion.
Chemical resistance
Excellent
Resists acids, bases and common solvents. Suitable for labels in direct contact with chemicals.
Mechanical strength
Very high
Very hard to tear or puncture. Keeps its dimensional integrity even under abrasion.
Dimensional stability
Doesn't stretch or shrink
Ideal for barcodes and identification data that must stay legible over the long term.
Relative cost
Higher than PP
The extra cost is justified in applications with demanding conditions of use. In controlled environments it may be unnecessary.
Polypropylene (PP)
The most versatile and economical option for most applications
Temperature resistance
Up to ~80 °C in reliable continuous use
Some grades reach 100 °C, but that's the material's limit. Above 80 °C sustained, polyester is the safe choice.
Chemical resistance
Good overall
Lower than PET against strong solvents. Suitable for moderate cleaning products and damp environments.
Mechanical strength
High
Somewhat lower than PET, but sufficient for the vast majority of logistics and food applications.
Flexibility
High — greater conformability
Adapts better to curved or irregular surfaces. A clear advantage on complex-shaped packaging.
Relative cost
Lower than PET
Very competitive for large volumes. Under moderate conditions of use, it offers very good value for money.
Section 2
Comparison table
A direct comparison of the properties most relevant to material selection in industrial applications.
| Characteristic | Polyester (PET) | Polypropylene (PP) |
|---|---|---|
| Max. temperature (continuous) | ~150 °C | ~100 °C |
| Solvent resistance | Very high | Good |
| Flexibility | Medium | High |
| Tearing / puncturing | Very resistant | Resistant |
| Outdoor / UV | Good (needs UV adhesive) | Good (UV-stabilised PP) |
| Cold chain | Good | Excellent (cold-chain stable PP) |
| Relative cost | Higher | Lower |
| Typical applications | Chemicals, automotive, metals and steel | Food, cold, logistics |
The temperature ranges shown correspond to continuous use conditions with standard adhesives. One-off conditions or the choice of special adhesives can extend these limits.
Section 3
When to choose polyester
Polyester labels are the right choice when you need characteristics that polypropylene can't guarantee. The four most common scenarios:
Scenario 1 — Aggressive chemicals
Direct exposure to solvents, concentrated acids or strong bases. PET keeps the label's integrity intact in environments where PP can degrade or lose adhesion over time.
Scenario 2 — Sustained high temperature
Temperatures above 100 °C sustained: ovens, drying processes, hot surfaces in automotive or metals and steel. PET with a high-performance silicone or acrylic adhesive is the standard for these cases.
Scenario 3 — Maximum mechanical strength
Labels that must withstand scratching, intense abrasion, rough handling or adverse storage conditions. PET's surface hardness makes it significantly more puncture-resistant than PP.
Scenario 4 — Permanent identification
Asset identification plates, traceability labels for the whole service life, industrial component identification with a service life of several years. PET's dimensional stability keeps barcodes scannable even after years of industrial handling; PP can deform slightly under prolonged tension, compromising readability.
Section 4
When to choose polypropylene
Polypropylene comfortably covers most industrial needs at a lower cost. There are four scenarios in which it actually outperforms polyester:
Scenario 1 — Cold chain
Cold-chain stable polypropylene keeps its flexibility and adhesion down to −40 °C. It's the benchmark material for labels in cold rooms, frozen goods and temperature-controlled logistics.
Scenario 2 — Curved or irregular surfaces
PP's greater flexibility lets it conform to complex-geometry packaging, pipes, bottles and other curved surfaces without the label lifting at the edges.
Scenario 3 — Tight budget and moderate use
When temperature, chemical and duration conditions don't require PET, polypropylene delivers very similar performance at a considerably lower cost. At large volumes, the price difference is significant.
Scenario 4 — Food and beverage
Compatible with food industry hygiene requirements. Resistant to moisture, condensation and the surface washdowns typical of food and beverage production lines.
Section 5
When the difference is irrelevant
When the environment presents no critical factor, PET and PP deliver practically identical performance throughout the label's service life. The materials debate only matters if at least one of the questions in the panel on the right gets a yes.
In practice, this covers most standard warehouse applications, general logistics and product identification with no chemical exposure. The thermal indifference range sits roughly between −20 °C and 80 °C: within that margin, with flat surfaces and a service life under 1–2 years, the difference in behaviour doesn't justify the extra cost of PET.
Decision criterion under standard conditions
When none of the demanding conditions is present, the choice should come down to cost and the type of adhesive required for the specific surface. Polypropylene will deliver the same result at a lower price.
Does any of these conditions apply? → then the difference does matter
Temperature > 80 °C continuously?
→ Polyester
Contact with strong solvents?
→ Polyester
Sub-zero temperatures or cold chain?
→ Polypropylene
Curved or irregular surfaces?
→ Polypropylene
Standard conditions or large volume?
→ Polypropylene
If your application involves combined conditions or doesn't clearly fit any of these criteria, contact us: we'll guide you with no obligation.
Keep reading
Related guides
Decision guide
How to choose the material for a label
A step-by-step methodology: surface, environment, printing and durability. The starting point before comparing specific materials.
Technical guide
Guide to industrial label adhesives
The adhesive determines the final bond as much as, or more than, the face material. Types, compatible surfaces and application conditions.
Resource library
See all resources and technical guides
All the material selection guides, adhesives, applications and frequently asked questions about industrial labelling in one place.
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