Self-adhesive labels (also known as self-sticking labels) are a type of label with built-in pressure-sensitive adhesive. They require no additional glue application—simply peel off the underlying release paper, and they can be directly stuck to the surface of various objects. Due to their ease of use and strong adaptability, they have become one of the most widely used types of modern labels.

Basic Structure

The core structure of self-adhesive labels consists of three indispensable layers:

Surface substrate (printing layer): The 'carrier' that bears graphic and text information, serving as the 'face' of the label.

Diverse materials: Common ones include paper-based materials (such as coated paper, kraft paper, writing paper, and fragile paper) and film-based materials (such as BOPP, PET, PE, PVC, and synthetic paper).

Functional adaptation: Paper-based materials are suitable for room temperature and dry environments (e.g., product price tags, document labels); film-based materials, on the other hand, have properties like water resistance, scratch resistance, and resistance to high and low temperatures (e.g., labels for beverage bottles and cosmetic containers).

Pressure-sensitive adhesive layer (adhesive layer): The 'adhesive core' of the label, which has inherent stickiness at room temperature and is key to achieving adhesion.

Characteristics: No heating or solvents are required; it can adhere to the surface of the object to be labeled with only slight pressure. Adhesion is affected by temperature, pressure, and contact time.

Types: Classified by adhesive durability into permanent adhesives (e.g., labels for food bottles, which are difficult to peel off) and removable adhesives (e.g., refrigerator stickers, temporary labels, which leave no residue after peeling).

Release paper (base paper / backing paper): The 'protective layer' that safeguards the adhesive layer, preventing the label from sticking to itself or the adhesive from failing.

Materials: Mostly silicone-coated paper (such as glassine paper, kraft release paper) or release films. Their surfaces are treated with silicone oil, resulting in weak adhesion to the adhesive layer, making them easy to peel off.