# Label adhesive by surface: glass, plastic and metal

> The same adhesive behaves differently on glass, HDPE, PET and painted metal. How to match glue to substrate, and why labels slide on recycled plastic.

Pillar: label-materials · Updated: 2026-11

**Our view.** Nine out of ten adhesion failures we are asked to look at are a standard acrylic on a low-energy plastic, not a bad film. Before changing material we would change the adhesive, and test on the production bottle rather than a stock sample, because recycled HDPE varies enough between batches to fail a test that passed last month.

Face stock gets the attention; adhesive decides whether the label stays. The same permanent acrylic that holds for years on glass can slide off a recycled HDPE bottle within a day, and the difference is surface energy, not glue quality.

## Surface energy in one paragraph

Adhesives bond by wetting a surface. High-energy surfaces — glass, metal, rigid PET — let the glue spread and grip. Low-energy surfaces — polyethylene, polypropylene, powder coatings — repel it. On those, a standard adhesive never fully wets out, so it holds by tack alone and fails under stress, moisture or time.

That is why "permanent adhesive" is not a single product.

## The matching table

| Surface | Adhesive | Notes |
|---|---|---|
| Glass | Standard permanent acrylic | Forgiving; works cold or warm |
| Rigid PET | Standard permanent | Good wet-out, clean bond |
| HDPE / PP | LSE acrylic | Specifically for low-energy plastics |
| Recycled HDPE | LSE, and test first | Release agents and blends vary |
| Powder-coated metal | LSE or rubber-based | Texture reduces contact area |
| Painted wall | Removable | Permanent takes paint with it |
| Kraft board | Standard permanent | Porous; bonds fast and hard |
| Frozen packaging | Freezer-grade | Standard turns brittle at −18 °C |

## Recycled plastic is the trap

Recycled HDPE is the most common failure we see. The resin contains release agents and blend variation that make the surface less consistent than virgin material, and a label that passed a test on one batch can lift on the next.

Two practical responses: specify an LSE adhesive, and test on the actual bottles rather than on a generic sample.

## Temperature at application

Adhesive needs contact and time. Applying below about 5 °C reduces initial tack, and a label applied cold may never reach full strength even after the product warms up.

If your filling line runs in an unheated space in winter, say so — a winter-grade adhesive exists for exactly this.

## What this means for buyers

**Name the substrate, not just the product.** "250 ml bottle" can mean glass, PET or HDPE, and each needs a different adhesive.

**Ask about recycled content.** If the bottle is rPET or rHDPE, the adhesive needs to be specified for it.

**Cold application is a specification.** Winter filling lines need a different adhesive, not a warmer room.

**Test on production containers.** A sample on a stock bottle proves the film; only your bottle proves the adhesive.

## Quick answers

**Why does a label slide off an HDPE bottle?**

HDPE has low surface energy, so a standard acrylic never wets out properly and holds by tack alone. A low-surface-energy adhesive is formulated for that plastic. Recycled HDPE is worse because release agents and blend variation make the surface inconsistent.

**Can I test adhesion myself before ordering?**

Yes, and you should. Apply a sample to the actual container, store it the way the product is stored, and check the edges at 24 hours, one week and one month. A peel test at a fixed angle and speed gives a number, but the edge check tells you what will happen in service.

## Sources

- FINAT Test Methods — peel adhesion and loop tack — https://www.finat.com/knowledge/finat-test-methods
- ASTM D903 — Peel or Stripping Strength of Adhesive Bonds — https://store.astm.org/d0903-98r17.html