The outermost layer of self-adhesive printing paper is the printing surface layer, which is the part of the label that directly carries the information. The printing surface layer can be paper, thermal paper, or synthetic film (such as PET, PP, PE). The surface is usually coated to enhance printability, ensuring clear display of text, barcodes, QR codes, or patterns. Different materials for the printing surface layer have different characteristics: paper surfaces are suitable for short-term use and general printing, while synthetic material surfaces are water-resistant, abrasion-resistant, and chemically resistant, suitable for long-term use or industrial environments.
Below the printing surface layer is the adhesive layer (pressure-sensitive adhesive layer), which is the key part that enables the self-adhesive printing paper to function. The adhesive layer usually uses pressure-sensitive adhesive materials, which have the characteristic of adhering easily at room temperature. Adhesive layers can be classified as permanent adhesive, removable adhesive, or reusable adhesive, depending on their application. Different types of adhesive layers can meet different adhesion strengths and usage environments, such as long-term fixation, temporary labeling, or repeated use. The bottom layer is a release liner or protective backing paper, used to protect the integrity of the adhesive layer during storage and transportation. The backing paper is usually coated with silicone oil or a smooth film, which makes it easy to peel off, allowing the label to be easily peeled off and flatly attached to the target surface during use.
