The main raw materials of the tag coated paper mainly include two parts: copperplate base paper and paint.
1. Copperplate base paper
Composition: Copperplate base paper is usually made from bleached chemical wood pulp or mixed with partially bleached chemical straw pulp on a paper machine. The wood or grass pulp is bleached to improve the whiteness and purity of the paper.
Characteristics: copperplate base paper requires uniform thickness, small scalability, high strength, good water resistance. The paper surface is not allowed to have spots, wrinkles, holes and other paper diseases to ensure the quality of coating and printing.
2. Paint
Composition: The coating part is mainly composed of high-quality white pigments (such as kaolin, talc powder, calcium carbonate, titanium dioxide, etc.), adhesives (such as polyvinyl alcohol, casein, modified starch, synthetic latex, etc.) and other auxiliary additives (such as gloss agent, hardener, plasticizer, dispersant, wetting agent, opalescent agent, fluorescent whitening agent, toner, etc.).
Characteristics: These components are uniformly coated on a coating machine and are dried and supercalendered to produce the final coated paper. The selection and ratio of coatings have an important effect on the gloss, color reproduction and printing adaptability of coated paper.
Species of wood
There are various kinds of raw materials for coated paper, such as poplar, pine, birch, willow and so on. Different types of wood have different characteristics, for example, willow is one of the varieties with higher lignin content, lignin is an important factor affecting the quality of paper, and the high content of wood can make better quality coated paper. Therefore, a number of factors need to be considered when selecting wood, including fiber length, lignin content and uniformity.
Sum up
The main raw materials of the tag coated paper are copperplate base paper and coating, of which the copperplate base paper is made of bleached chemical wood pulp or with part of the bleached chemical straw pulp, while the coating is composed of a variety of high-quality white pigments, adhesives and other auxiliary additives. At the same time, there are various types of wood, commonly used poplar, pine, birch, willow, etc., when choosing wood, you need to consider a number of factors to ensure the quality of coated paper.