PP 28mm Caps: Necessary of Syrup Bottles

When we think about syrup bottles, we often focus on the material of the bottle-glass, PET, HDPE-or the ease of squeezing and pouring. But there's another critical component that rarely gets the spotlight: the cap. Specifically, the PP 28mm cap is one of the most widely used closures for syrup bottles, and for good reason.

Though small, this cap plays a big role in product safety, user experience, and packaging efficiency. Let's take a closer look at what makes the PP 28mm cap an industry standard for syrup packaging.

28mm child resistant cap for liquid

What is a PP 28mm Cap?

The “28mm” refers to the diameter of the neck it fits-specifically, 28mm standard neck finishes, which are common for food-grade bottles. “PP” stands for polypropylene, a type of plastic that is lightweight, durable, and food-safe.

These caps can come in a variety of designs:

Standard screw caps

Flip-top caps

Child-resistant closures

Tamper-evident designs

For syrup bottles, the 28mm cap is usually a screw-on or flip-top style, often with a tamper-evident band for safety.

HDPE syrup bottle with crc cap

Why PP is the Ideal Material

Polypropylene (PP) is one of the most used plastics in food packaging due to its ideal balance of strength, heat resistance, and chemical stability. Here’s why PP is such a great match for syrup bottle caps:

Food-safe and compliant with FDA and EU regulations.

Resistant to sticky syrups and sugar-based liquids, with no degradation over time.

Handles heat — suitable for hot-fill processes often used for syrups.

Fully recyclable in many municipal systems (marked as #5 plastic).

Key Features of a PP 28mm Syrup Bottle Cap

Leak-Proof Seal

A properly designed 28mm cap provides a tight seal that prevents leaks, even when the bottle is inverted or stored sideways.

Tamper-Evident Safety

Most syrup brands use caps with a tamper-evident band, which breaks away when the cap is first opened. This builds consumer trust by showing the product hasn't been tampered with.

Smooth Pouring & Reclosing

Whether it's a flip-top or screw-on design, these caps offer a clean, controlled pour, reducing mess and waste-something especially important for sticky syrups.

Compatibility

The 28mm neck finish is a widely accepted industry standard, making it easy to match bottles and caps from different suppliers without special tooling.

Customizable for Branding

PP caps can be manufactured in various colors, textures, and embossed logos, helping brands reinforce their identity right at the point of use.

PET amber bottle

Sustainability Matters

While PP isn't as widely recycled as PET, it's still a recyclable material, and efforts are growing globally to improve polypropylene recycling streams. Some manufacturers also now offer recycled PP (rPP) caps to reduce reliance on virgin plastic.

Brands aiming to meet sustainability targets can pair PP caps with recyclable PET or HDPE bottles for a fully recyclable packaging solution.

For syrup producers looking for a dependable, customizable, and cost-effective closure, the PP 28mm cap continues to be the go-to solution.