Papermaking chemicals refer to the various chemicals and additives used in the papermaking process. (Such as sizing additives, wetting agents, etc.), paper processing chemicals (such as fungicides, eliminate the use of chemicals, such as cooking chemicals (such as cooking auxiliaries, deinking agent, etc.), papermaking chemicals Foam agent, coating agent) and pollution control chemicals and other four categories. Its purpose is to improve the quality of paper and production efficiency, improve operating conditions, reduce manufacturing costs, increase economic efficiency and the development of new paper.
Paper industry is the traditional industry of light industry, because the paper consumption and production level also represents a national and regional economic and cultural development level, paper industry and the national economy show synchronous development trend. China's paper and paperboard production increased from 30.5 million tons in 2000 to 86.4 million tons in 2010, nearly doubled in 10 years, has become the world's largest producer of papermaking; China's total consumption of paper products to 18 % Of the growth rate, becoming the world's second largest consumer of paper products. With the increasing use of papermaking chemicals in the paper industry, the average annual growth rate of paper chemicals in the future is expected to reach 9%. By 2015, the papermaking chemicals market will exceed 50 billion. Papermaking chemicals industry in the domestic market prospects for the development of optimism.
Sizing agent is a papermaking additive, mainly divided into pulp sizing and surface sizing. In the paper sizing can improve the paper water, oil, anti-printing ink and other properties, while improving the smoothness, hydrophobicity, printing adaptability.
Method of use: sizing there are two ways, one is in the paper before the formation (beating or ingredients) sizing agent added to the pulp called pulp sizing, the other is formed in the paper after finishing Paper or cardboard surface is called surface release. Pulp sizing agent mainly rosin sizing agent, synthetic sizing agent, paraffin sizing agent and neutral sizing agent. Surface sizing agent and neutral sizing agent. Common models QT-7N surface sizing is mainly to improve the smooth surface of the paper, reduce porosity, to prevent surface fluff and hair loss. Used more modified and unmodified starch, but also the use of PVA. There are also paraffin emulsions, animal gums, carboxymethylcellulose, polyurethanes, styrene-maleic anhydride copolymers, acrylic and acrylate copolymers, dihydroxy fatty acid compounds, and the like.
Surface sizing is a process in the course of paper or cardboard processing, usually at the end of the drying section of the machine, so that the sheet is sprayed with a layer of glue when it is not completely dry but with a certain strength, Cardboard surface to form a layer of film, so as to achieve the purpose of changing the performance of paper or cardboard.
From the development of the paper industry, paper-making surface sizing is one of the indispensable processes, through the surface sizing can be added to improve the performance of paper or increase the paper or cardboard water resistance of surface additives.
Originally, due to the technical level and paper requirements of the restrictions, surface sizing agent can only be used in special paper, such as: banknote paper, bond paper, sea paper and so on. With the improvement of the technical level of the paper industry, the surface sizing of paper has become a conventional paper processing process, especially in recent years due to the printing, copying, fax popularization of cultural paper, wrapping paper and corrugated surface performance, strength and Water resistance made a higher demand, so the paper industry in the continuous exploration of the new surface sizing technology