In general self adhesive paper labels are a combination of silicone liner and adhesive layer and face material. The liner is one and the same for almost all types of self adhesive labels. (paper thermal transfer labels, paper direct thermal labels, foil labels etc.).
Self adhesive labels of different manufacturers differ in the type of the face material and the adhesive layer. Depending on the designation of self adhesive labels and the environment they shall be used in, adhesives are developed, corresponding to the specific requirements of each application. The most often used adhesives are acrylic based and are characterized with very wide temperature range of application (there are special developments for temperatures over 3000C) and are comparatively universal toward the materials, they can be stuck on. For specific conditions, for example low temperatures (up to 400С), high humidity and product pollution, the so called “hot-melt” adhesives are used. Adhesives with very specific characteristics are also used, as for example “removable” adhesive, that does not leave traces and remains entirely on the label, when it is unstuck from the product , or adhesive that permits multiple sticking and peeling off the label. The choice of suitable adhesive for each application is a very important task, aiming to guarantee the necessary adhesive properties of the labels, which will be used.
Self adhesive paper labels can provide good balance between quality and price for many general applications in labeling. Self adhesive paper labels are used for identification of products in retail and wholesale trade, food industry, transport and logistic, production plants, for price labels, for advertising labels, rating plates, etc.
We are a manufacturer of self adhesive paper labels that can be printed by thermal transfer or direct thermal print that can be pre-printed with logo or other permanent information, by flexo printing. According to the print method, self adhesive paper labels are divided in thermal transfer and direct thermal. When printing the two types of labels a method is used, in which the printout is produced through transfer of temperature, generated from the so called thermal print head. Thermal transfer printing uses a ribbon to produce long-lasting image on a wide variety of materials. No ribbon is used in direct thermal printing, which produces the image directly on the label, on which preliminary a thermal sensitive layer is applied. Direct thermal print is more sensitive to light, heat and abrasion, which reduces the life of the labels printed through this method.
Self adhesive paper thermal transfer labels are a combination of supporting layer, adhesive layer and face material, made from various kinds of papers – uncoated, coated, or with additional coating, depending on the designation and the label print technology. One of the technologies for printing self adhesive labels is the thermal transfer printing, which creates an image by melting solid ink, coated on a foil ribbon and transferring it onto a receiving material. The receiving material can be uncoated paper, coated paper, or foil. Though almost self adhesive labels can be printed by thermal transfer method, the best results are achieved with the use of carefully selected materials. Depending on the type of print and the quality level that customers require, a suitable ribbon must be used in combination with an appropriate and correctly set printer. All products have a guarantee for quality thermal transfer print, but good image can be obtained with selected thermal transfer ribbon.
Self adhesive paper direct thermal labels are a combination of liner, adhesive layer and face material, made from various kinds of papers.
The production of a thermal paper begins with an uncoated base paper, which is transformed into a direct thermal paper with the application of a chemical coating. The first chemical layer, the under layer, prevents the heat generated by the thermal head from dissipating through the paper. This ensures better resolution when printing at low energy. The second chemical layer, the thermal layer, contains a dye and developer. When exposed to the 2500C, emitted by the thermal head, the thermal layer melts, bringing the dye into contact with developer and forming the thermal image. The link between the two chemicals in the thermal layer is quite fragile and can be broken through exposure to oil, plasticizers or water, fading the printed image. Barrier coatings are added for protection.