Standard self-adhesive labels consist of three layers: a surface substrate (printed surface), a release layer (silicone oil substrate), and an adhesive. The surface material includes paper and film; paper types include coated paper and offset paper, while film types include PET, PP, and PVC. Adhesives are classified by tackiness into weak, strong, and super-strong types. The backing paper (release paper) isolates the adhesive and commonly includes glassine paper and kraft paper.
Self-adhesive labels offer advantages such as no need for glue application, no pollution, quick labeling, strong adhesion, heat and moisture resistance, and resistance to aging. Certain materials, such as polyolefin labels, also possess waterproof, chemical-resistant, UV-resistant, and autoclave-safe properties.
Most self-adhesive materials are in roll form, with a small number in sheet form. In terms of measurement, paper labels are measured in grams per square meter (g/m²), while film labels are measured in micrometers (µm).
Environmentally friendly labels are becoming a development trend, such as those using solvent-free adhesives, biodegradable materials (e.g., seaweed-based adhesives, bagasse-based adhesives), and water-based UV adhesives. Solvent-free self-adhesive labels and paperless thermal self-adhesive labels also possess environmentally friendly and low-carbon characteristics.