Variety of printing paper

In the 1980s, China's printing industry and the paper industry jointly completed the transition from letterpress printing to offset printing and from the production of letterpress printing paper to the production of offset printing paper. At present, China's letterpress printing is almost entirely replaced by offset printing.
Modern offset printing requires that the printing paper has a smoother surface, better printing performance, and can withstand large changes in temperature and moisture. Internationally, a series of new varieties of mechanical pulp printing paper have been developed. In recent years, digital printing technology, office automation and the development of personal computers have brought newer and higher requirements to paper.
Now, consumers have higher requirements for print. People not only want the necessary knowledge and information, but also hope to enjoy the beauty through the reading and browsing of printed materials.
In a long period of time, the production and consumption of paper will continue to develop steadily. However, paper varieties will undergo major changes, and the paper industry will also face new challenges for consumers to spend less, do more, and do good things.
In the 21st century, the trends in the development and development of printing paper varieties are:
Meet the requirements of multicolor and color printing;
Improve strength and reduce ration;
Improve the paper's optical performance and surface performance;
Increase the amount of fillers and pigments;
Use a variety of effective chemical additives;
Adapt to the requirements of new printing ink, printing process and printing equipment, with good printability and operating efficiency;
To create conditions for the continuous expansion of the use of recycled fiber pulp (DIP);
Develop a series of products to achieve a balance between use, quality and production costs.
The following is a brief introduction to the development of new varieties of international printing paper, mechanical pulp printing paper series and chemical wood pulp printing paper series:
First, the new varieties of mechanical pulp printing paper series can be divided into two categories: The first category is based on newsprint to improve, enhance and develop new types of extended non-coated mechanical pulp printing paper, the second is A new type of coated mechanical pulp printing paper for color printing.
1. Non-coated mechanical wood pulp printing paper new varieties.
After a revolution in printing technology in which relief printing was transformed into offset printing, offset printing and thermosetting inks have become the mainstream of newspaper printing. At the same time, newsprint users no longer care about newsprint ash content below 3% of the quality indicators, but hope that newsprint should be low-quantity, high-intensity, good optical performance and printing performance.
Therefore, paper manufacturers have added fillers to newsprint in order to improve the opacity of newsprint and the ink receptivity of printing inks; and to surface-treat newsprint paper to prevent them from falling off during offset printing. In the raw materials, it also minimizes the use of chemical wood pulp to make heavy use of recycled fiber pulp, and developed a series of new varieties such as refined newsprint (Improved Newsprint, referred to as IN paper) and advanced newsprint (Super Improved Newsprint, SIN for short). Paper), super calendered paper (SC paper), surface-treated supercalendered paper (ST/SC paper), and pigmented paper (MFP paper).
Supercalendered paper (SC paper) is a non-coated mechanical wood pulp printing paper that was first developed by the Finnish paper industry using mechanical pulp as the main fiber material, adding a considerable number of fillers, and finishing with a supercalender. It can also be said graphically that SC paper is a high-fill, high-ash, high-grade newsprint paper. The SC paper has a basis weight of about 60 g/m 2 . SC paper has three varieties; SC-A paper filler content of 20 to 30%, SC-B paper filler content of 15%, SC-C paper without filler.
SC-A paper is a typical high grade non-coated mechanical wood pulp paper. In the European market, the competition between SC paper and low weight coated paper (LWC paper) is fierce. Some Finnish papermakers believe that the quality of SC-A paper can catch up with LWC paper. SC paper is still rare in the Chinese market. The domestic Fujian Longyan Paper Industry Co., Ltd. invested 6.8 billion yuan to establish a production line that can produce SC paper. The production line was trial-production in 1998 and high-quality newsprint was produced in 1999. It was welcomed after it was put on the market. The plant uses the masson pine as raw material for pulping and is now adjusting its technology to meet the requirements for the production of SC paper.
Refined newsprint (IN paper) and premium newsprint (SIN paper) are premium newsprints with fillers and surface treatments. After this treatment, not only can the optical properties and printing performance of the paper be improved, but also the whiteness of the paper can be improved, overcoming the problem of insufficient whiteness due to the use of recycled pulp.
The surface-treated supercalendered paper (ST/SC paper) was surface treated with a predetermined amount of size press and was finished with soft calendered SC paper. ST/SC paper has good smoothness, gloss, and gloss contrast.
Pigmenting Paper, also called Machine Finished Pigmented Paper (MFP paper for short), is a new type of mechanical pulp printing paper developed in Japan. It is called "Bitokoshi" in the Japanese market. The basis weight of MFP paper is 49 to 54 g/m2, which is an inexpensive substitute for LWC paper. The amount of fillers and pigments on the surface of MFP paper increases, and printing performance and whiteness improve.
2. Coated mechanical pulp printing paper new varieties.
New types of coating machinery wood pulp printing papers include: Lightweight Coat-ed Paper (LWC), Film Coated Offset Paper (FCO), and Machine-finished Coated Paper (MFC for short). paper). These varieties all have good color printing performance, and can be used to print inserts, leaflets, coupons, catalogues, samples, magazines, and other printed materials, of which LWC paper is particularly popular in the market. The three kinds of papers are described as follows:
Low weight coated paper (LWC paper): In the international market, North America's No. 5 low-quantity coated paper is used as the standard product. The basis weight of LWC paper is 58 to 61 g/m2, and the coating amount per side does not exceed 7 g/m2. The raw material of LWC paper base paper is still mechanical pulp, but in order to meet the strength requirements of raw paper, there are more bleached sulfate chemical wood pulp. The whiteness, gloss, and smoothness of the LWC paper and the chemical pulp ratio in the base paper are the highest in the mechanical pulp printing paper product line. LWC paper has good opacity and bulk.
Some “low-quantity coated paper” in the Chinese market, the raw material of fiber in the base paper is chemical wood pulp and chemical grass pulp, and no or less mechanical wood pulp is used, so all the quality indicators cannot meet the requirements of genuine LWC paper. In the Chinese market, more and more imported LWC papers have been imported, and imports have increased exponentially over the years.
The coating weight of film-coated offset printing paper (FCO paper) is 51-60 g/m2, and the coating amount per side is 6-8 g/m2. The gloss of formed paper is close to the gloss of LWC paper, and the roughness is slightly higher than that of LWC paper. Degree, looseness and opacity are better. The paper ash of FCO paper is divided into 10 to 15%, and the ash content of the base paper is only 4 to 5%. FCO paper base paper has more mechanical wood pulp content and less chemical wood pulp content. Therefore, the production cost of FCO paper is low.
Many papermaking companies in North America and Northern Europe have produced FCO papers and believe that FCO papers have good competitiveness and market prospects. In the Chinese paper market, no FCO papers have yet been seen.
Second, in the 21st century, digital information technology has received unprecedented attention, and the printing industry is no exception. With the continuous advancement of science and technology, new types of paper serving digital information technology are emerging. These newly developed paper types can be collectively referred to as digital printing paper.
Digital printing paper is almost always made from bleached kraft chemical wood pulp with a high degree of brightness, with a uniform blue-white color. For the production of digital printing paper, bleached conifer kraft wood pulp and bleached broad-leaved tree kraft wood pulp are commonly used to produce a paper sheet with good strength, opacity, bulk, stiffness and whiteness, and uniform organization. , Paper smooth, clean, no fiber bundles, spots and dust, lint-free powder, good optical properties and printing performance. In the manufacturing process, it is generally necessary to add certain fillers, such as precipitated calcium carbonate.
Digital printing paper uses neutral paper and neutral sizing, and uses a variety of chemical auxiliaries such as retention aids, reinforcing agents, and lubricants. It has been reported that non-coated ink-jet printing papers may have different effects with different sizing agents, so it is necessary to use sizing agents in production.
Retention aids are another common adjuvant in the production of digital printing paper. The use of retention aids tends to affect the formation of the paper. This problem should be taken into consideration when using a particulate retention aid. For papermaking using recycled fiber pulp, in order to compensate for insufficient fiber strength, starch or synthetic resin reinforcing agents may be used to increase the strength of the paper.
Digital printing paper is mostly small-size paper, and has a high requirement for the fiber binding strength, cleanliness, and two-sided difference of the paper surface. In order to prevent the paper from falling into powder and entraining burrs, shards, and confetti, the cutting blade must be sharp and sharp. In order to increase the paper fiber binding force, a predetermined amount of size press can be used for surface treatment. The paper machine should use an advanced Topfor-mer to minimize the discrepancies on both sides of the paper sheet. Soft calendering should also be used to obtain good smoothness.