Release Paper is an essential material used across multiple industries for adhesive coating, label backing, composite lamination, and various industrial applications. This article explains what release paper is, how it’s made, its main applications, and a brief summary highlighting its importance in modern production processes.

1. What Is Release Paper

Release paper, also known as silicone-coated paper, is a specialty substrate designed to prevent adhesives from sticking to unwanted surfaces. It acts as a carrier or protective liner in self-adhesive products, such as stickers, labels, tapes, and composite materials.

The key characteristic of release paper lies in its surface coating, which allows materials with adhesive layers to peel off easily and cleanly. The base paper can be made from Kraft Paper, glassine paper, or sulfur-free paper, depending on the desired properties such as transparency, strength, and release smoothness.

Common Base Types:

Sulfur-free paper is particularly valued for its non-yellowing, high-purity, and stable surface properties, making it ideal for cleanroom and high-precision adhesive applications.

2. How to Make Release Paper

The manufacturing process involves carefully controlling each step—from selecting base materials to coating, curing, and cutting. Below is a detailed overview:

Step 1: Base Paper Selection

The process begins with selecting a high-quality sulfur-free or kraft base paper. The choice depends on the target application:

• Sulfur-free paper offers superior smoothness and cleanliness, preferred in electronics or optical film industries.

• Kraft or glassine bases are used for general industrial tapes or stickers.

Each roll is inspected for surface defects, moisture content, and tensile strength before coating.

Step 2: Surface Treatment

The base paper undergoes surface treatment to enhance coating adhesion and uniformity.

• Corona treatment increases surface energy for better silicone anchoring.

• Calendering compresses the surface, improving flatness and coating smoothness.

• Dust removal ensures the paper remains clean before entering the coating section.

This stage is critical to ensuring consistent coating quality and preventing pinholes or uneven release levels.

Step 3: Silicone Coating

The treated base paper is coated with a layer of silicone release agent. This is the heart of release paper production.

• The coating may use solvent-based, solventless, or emulsion silicone systems depending on end-use requirements.

• Coating can be applied by knife-over-roll, gravure, or Meyer bar methods.

After coating, the paper passes through a curing oven where the silicone polymerizes and bonds permanently to the paper surface, forming a smooth, low-energy layer that provides controlled release.

Step 4: Curing and Cooling

Once coated, the paper passes through an oven at 120–160°C, depending on the silicone type. The curing process ensures proper crosslinking, enhancing both release performance and thermal stability.
After curing, the paper cools gradually to prevent surface tension marks or warping.

Step 5: Slitting and Customization

The cured paper is rewound into large master rolls, then slit into custom widths and lengths based on client specifications.

• Customizable Widths: from 500 mm to 2000 mm (depending on machinery).

• Customizable Lengths: typically 100 m to 3000 m per roll, adjustable for application type.

• Precision slitting ensures even edges, minimal dust generation, and stable unwinding performance.

High-precision slitting machines, like the one shown in the image, maintain dimensional accuracy and surface integrity, making the product ready for downstream adhesive coating or lamination.

3. Applications of Release Paper

Release paper plays a crucial role in adhesive, composite, and industrial manufacturing processes. Its ability to provide smooth release and protection makes it indispensable in multiple sectors.

A) Adhesive Labels and Stickers

Used as a backing liner for pressure-sensitive labels and decals. It allows easy removal during labeling while keeping the adhesive uncontaminated.

B) Industrial and Masking Tapes

Acts as a separator during winding and unwinding, ensuring adhesives do not stick together. Ideal for automotive, electronics, and packaging industries.

C) Composite Materials and Prepregs

In the aerospace and wind energy sectors, release paper serves as a release liner for resin-infused composite prepregs, preventing resin adhesion during curing.

D) Medical and Hygiene Products

Used in wound dressings, transdermal patches, and hygiene pads to protect adhesive surfaces while ensuring sterile and residue-free removal.

E) Electronic and Optical Film Processing

Sulfur-free release paper is especially valued in clean manufacturing environments—used for optical films, touchscreens, and flexible printed circuits where dust control and neutral pH are essential.

Summary

Release paper is a functional, precision-engineered material that ensures smooth separation between adhesive layers and support surfaces. It is essential for industries requiring clean, stable, and easily releasable surfaces.

Using sulfur-free base paper enhances environmental safety, dimensional accuracy, and performance stability, especially for high-end industrial and electronic applications.

The production process—from surface treatment to silicone coating and precision slitting—ensures customizable solutions for various industrial needs.
With adjustable widths, lengths, and coating types, release paper remains a critical component for manufacturers seeking quality, consistency, and clean release performance in every layer of their production.