Process methods and techniques for improving the quality of carton paper

Abstract : This article summarizes the variety and quality requirements of carton paper, describes the process control methods for carton production, and looks forward to the development trend of paper carton production technology.
With the continuous development of the market economy, the internationalization of the market has become increasingly evident. The requirements for the packaging of goods are getting higher and higher. As a packaging product that meets today's environmental protection requirements, paper packaging products have become more and more prosperous. Carton as a representative of paper packaging products, with the rapid development of import and export trade, the amount is increasing, the quality and cost requirements are getting higher and higher. It is predicted that the total amount of paper packaging paperboard in China will reach 24 million tons in 2005 and 32.5 million tons in 2010. The paperboard required is mainly high-strength corrugated paper, kraft linerboard, Whiteboard paper and coated whiteboard paper. In today's increasingly fierce market competition, how to minimize costs while ensuring quality is the main issue facing cartons and related industries. Carton paper is the main raw material for the production of cartons, and it occupies a pivotal position in the manufacturing cost of cartons. Therefore, the quality of the carton paper and the cost of the carton directly affect the competitiveness of the carton in the market. This paper describes the key process of carton paper production to improve the quality of carton paper and provide technical conditions for the production of inexpensive cartons.
First, the box paper and its quality requirements Currently in the production of paper cartons in the process of the main paper are roughly the following: First, for the production of coffins or corrugated corrugated paper or corrugated paper, its quantitative in the 90-120g/m2 . At present, 112g/m2 is commonly used, and it gradually develops to low-quantity direction. The second method is used for carton cover or bottom liner. Commonly used is normal linerboard or kraft linerboard. 125-400g/m2 or so; the third is used for medium and high-grade carton packaging paper, usually used is white paper, coated white paper or leather coated white paper, the quantitative in 125-400g/m2 or so. With the increasingly fierce competition in the market, the quality requirements for these types of carton papers are getting higher and higher. Table 1 and Table 2 are the national standards for the above-mentioned types of carton paper.

Table 1 National Standards for Corrugated Paperboard and Linerboard (GB13024-91, GB13023-91)

Table 2 National Standard for Single-coated Whiteboard Paper QB1011-91

Among the quality indicators listed above, the ring pressure index, burst resistance index, stiffness, smoothness (roughness), folding resistance, and printing performance are the main performance indexes of carton paper, of course, with cardboard, carton, With the continuous development of printing machinery technology, the speed of stand-alone machines is getting faster and faster. Besides the above-mentioned some quality indicators for carton paper, other requirements such as crack length, roughness, and surface printing strength will also increase.
Second, the main raw material for the production of carton paper From the production point of view, there are good quality raw materials may produce a good product. Waste paper, especially waste corrugated cardboard, grass semi-chemical pulp (chemical pulp), hardwood wood semi-chemical pulp (mainly NSSC pulp) unbleached kraft pulp, straw pulp, etc. can be used as raw materials for the production of carton paper. . With the increasing attention to environmental protection and the continuous development of waste paper recycling technologies, the recycling rate of waste paper that has been referred to as “urban forest” has become increasingly high in the world, and its recycling efficiency in advanced countries has increased. It reaches 70%. Waste corrugated linerboard (also known as OCC) is the main raw material for the production of carton paper. With the rapid economic development, its demand is increasing. In China, many manufacturers, in addition to using domestically produced OCC, many manufacturers in the coastal provinces rely on imported waste paper, mainly from waste paper in Hong Kong, the United States, Canada, or other European countries. The main reason is that domestic waste paper is of good quality. Or the quantity can not meet the needs of production, especially in quality. In addition, some manufacturers use wheat straw half chemical pulp or even chemical pulp to produce carton paper. This is related to the proportion of raw materials in China's paper industry, a considerable part of the raw materials for grass, but also related to China's waste paper recycling management and policy is not perfect. Therefore, it is certain that with the increasing demand for paper for carton, the raw material for the production of carton paper—waste paper is mainly OCC supply will become increasingly tense, how efficient is it?