CCK release paper (Clay Coated Kraft Paper) is a high-end release paper that is coated with ceramic clay (porcelain clay) on the surface and then coated with a release agent. It is commonly used in industrial scenarios that require high flatness and temperature resistance.

Meaning and Raw materials

CCK is an abbreviation for "Clay Coated Kraft", which is made by coating a special layer of clay (porcelain clay) on the surface of all wood pulp kraft paper, and then coating it with organic silicon release agent. The raw paper pulp requires a beating degree of not less than 45° SR, an ash content of not more than 2%, and a surface water absorption of not more than 30g/m² to ensure the stability of subsequent coating and release effects.

Conventional Weight and Size

Weight range: commonly ranging from 50g to 200g, mainstream specifications include 60g, 65g, 76g, 80g, 90g, 100g, 120g, 140g, 160g, etc.

Width: Commonly between 970mm and 1600mm, such as 1020mm, 1090mm, 1270mm, etc., some manufacturers can cut according to their needs.

Thickness: usually in the range of 0.05mm to 0.16mm.

Technical Indicators

Release force: can be customized according to needs, with a conventional range of about 5g to 40g, and some manufacturers also provide a wider range of 1g to 800g products.

Process control: The coating amount of clay is usually not less than 6.0g/m ² to ensure surface smoothness and prevent excessive penetration of silicone oil.

Characteristics

Physical properties: Good stiffness, dense texture, high tensile strength, and excellent dimensional stability.

Surface characteristics: high flatness, uniform coating, good smoothness, suitable for printing.

Temperature resistance: The high temperature resistance is better than that of ordinary PE coated release paper, and it can achieve high temperature curing of organic silicon.

Environmental friendliness: It belongs to non plastic release paper and is often referred to as "green" paper.

Limitations: Relatively poor flexibility, prone to breakage; Long term exposure may cause aging and brittleness.

Main Purpose

High end labels and tapes: used for high-end labels, computer labels, various tapes, and self-adhesive ethylene films.

Electronic die-cutting: suitable for electronic die-cutting processing that requires certain cleanliness and stability.

Composite materials and carbon fiber: As the carrier of carbon fiber prepreg, it is required to have good compatibility with various resin systems.

Medical and packaging: used for high-grade medical dressings, facial mask and gift packaging.

Overall, CCK release paper occupies an irreplaceable position in high-end labeling, electronic die-cutting, carbon fiber composite materials, and other fields due to its flat surface, excellent stiffness, and high temperature resistance brought by clay coating. Although its flexibility is not as good as PE coated release paper, and long-term use requires attention to aging issues, CCK is still one of the preferred choices in scenarios where there are clear requirements for dimensional stability, plastic free environmental protection, and temperature resistance processes. In actual selection, it is recommended to confirm the coating process and silicone oil system with the supplier based on specific weight, release force, and width requirements to achieve the best bonding and peeling performance.