At present, Asian countries, even the most developed Japanese paper industry, the use of synthetic sizing agent is relatively small, there are still about 70% of the use of adhesive tape rosin series sizing agent for sizing.
In 1807, foreign countries began to use saponified rosin size, and gradually developed, all made in the paper mill. In 1955, rosin was modified with maleic anhydride two anhydride, and then saponified to prepare fortified rosin size. (this kind of sizing agent began to be used in 1975, and natural rosin saponification gum was used before 1975). In 1960, synthetic sizing agent AKD (domestic use was started in 1992). In 1984, the United States Hercules company developed cationic emulsion rosin sizing agent, and began to be widely used in the paper industry in 1988.
Rosin is called acid resin by a series of three tranexamic acid which is a complex mixture of rosin acid, is the main component of the series, its molecular formula is C19H29COOH, the relative molecular mass of 302.04. According to different sources, rosin can be divided into three categories: self tapping pine trunk, collecting turpentine, processed rosin; harvesting after leaving the root sections by solvent extraction, extraction and processing by rosin; oil recovery to deal with pine kraft pulp, and processed oil rosin. Among them, the best quality is fat rosin. According to statistics, rosin and turpentine have more than 400 uses, it is an important industrial raw materials, can be widely used in soap, paper, rubber, coatings, chemicals, pharmaceuticals, food, plastics, electricians, pesticides and other industries.
Domestic production of 70% of the total amount of paper and paperboard requires internal sizing, in which 70% of rosin sizing agents. By 2020, the proportion of rosin dispersed in rosin sizing agent (mainly cationic dispersed rosin) will reach 50%, and its annual demand will increase from 57 thousand and 10 tons in 2015 to 111 thousand and 510 tons in 2020. It can be seen that there is great market development space for cationic dispersed rosin size based on the slight modification of rosin. |
