Paper is a felted sheet formed on a wire from a water suspension of fibers and is composed of a network structure created by the hydrogen bond of fibers. The air volume in the network of paper reaches to about 50 % of its total volume. The paper making process including pulping, stock preparation, forming, pressing and drying strongly affect not only the characteristics of the individual fiber but also that of the network structure of the paper. These characteristics, added history-dependent nature of stress and moisture change, produce the properties of paper that the user desires, for instance, hygroexpansivity, curl, printability and runnability.
As the definition in JIS (Japanese Industrial Standards) “coating is to apply agent to basis paper by coater, in order to give the characteristic adapted for uses, like printing and packing.” The characteristic depends on printing system, such as offset, rotogravure, thermal, ink jet, and electrophotographic print. This paper describes the classification, the feature, and the manufacture method of coated paper for offset print which is the mainstream of mass print. As paper is the aggregate of pulp, such as plant fiber, calendering is necessary to gain uniform thickness and flat and smooth surface. However, unevenness of several microns to several 10 microns remains in the surface even after calendering. We use coated paper to obtain good flatness and smoothness which cannot be attained in non-coated paper. And the coated layer makes it possible to design desirable gloss and brightness, and to form capillary which enhance absorption of ink solvent.
The concept of “High Performance Paper” seems to be an uncertain because it varies with times and/or individuals. Therefore, this paper describes high performance papers which I personally think. We investigate and utilize materials including new fibers, powders and chemicals and/or techniques including paper making, impregnating and coating when we need to give higher performance to paper. In addition, I will introduce high performance papers which I have developed.
This states the definition of the synthetic paper as conceived by the author and viewed its history. For the production method, I have briefly defined it while referring to the production method of the synthetic paper as put together by Yupo Corporation. Also, for the market of the synthetic paper, I have described it in each of the segments.
Although inkjet printing technology is applicable to a wide variety of substrates, specially designed media which are optimized for ink absorbency, uniformity whereof, print color intensity, waterfastness, lightfastness, oxidant resistance and runnability on printers etc. are necessary to obtain high quality print. Plain paper, matte coated paper, cast paper and resin coated paper are the most commonly used inkjet recording papers and they are designed to have properties required for intended purposes. As technology of the printers advances, some new characteristics that have not been important are being required.
In recent years, there has been a high growth rate of digital color electrophotography systems for office and publishing market application. The ultimate objective in digital printing media is to deliver printed output that satisfies customer requirements and expectations. To achieve this objective, we must be able to control the many factors that affect print quality and paper handling. Paper properties, such as smoothness, electrical resistivity, permeability, stiffness, coefficient of friction, surface energy, gloss and dimensional stability, play a critical role in the quality of printed output. To understand the trend in image quality and runnability of media for printing systems, the imaging media properties and their influence on current electrophotographic printings are reviewed.
Paper has been the most desirable substrate for recording sheets. However, it has many troublesome characteristics using for substrate of “thermal” recording sheet. The primary is its capricious thermal conductivity on parts of it. It causes luck of developed density uniformity and loses image quality. This paper describes the designs of base paper used for thermal recording sheets.
Process evolution for secondary fiber production has increased a recovery ratio of waste paper and is forecast to continue in the future. It is environmentally driven and will require the utilization of office wastes and magazine wastes for newsprint and printing paper production. Two important technologies are emerging: deinking of toner printed paper and removal of stickies.
When image information is conveyed with paper media, the information is greatly altered by the paper properties. Printing-related properties of paper and their definition and testing methods were described with reference to JIS specifying the testing methods. Paper is hygroscopic and the standard atmosphere for testing paper is specified to be 23°C and 50% relative humidity. Basis weight, thickness and density were described as structural parameters. Illuminant C diffuse illumination/normal view is the standard optical condition, and details of brightness, opacity, color and gloss were explained. High opacity peculiar to paper is ascribed to its high specific light scattering coefficient. Then, its calculation method and difference between paper and plastic sheets were demonstrated. For mechanical properties, tensile strength, folding endurance, tear strength and paper-to-paper friction were described. Finally, it was reported as a recent trend of ISO standard that new testing standards about recycled pulp and paper are being established.
Paper has a quite rich, colorful history, whose origin comes from China. But J. Gutenburg invention sparked a revolution in mass communication in Europe and the demand for paper created the need for greater efficiency in production. The increasing volume of paper consumption has becomes a complex environmental matter and one of the biggest problems is the huge volume of paper used as high quality printing material is still wasted. This paper proposes the change of coating system to produce coated paper from doctor coating to skin coating system to achieve excellent coverage of the base paper without any direct machine contact. There is no need for the blades, rods or backing rolls of conventional methods and makes it possible to use recycled pulp.
With the advent of digital technologies, more and more information is easily accessible to everyone through electronic media. It is also often pointed out that digital technologies could drive away papers used widely as typical analog media. Both paper and electronic media bear two important functions: “memory” and “display”. Obviously, papers are more friendly as an interface to human; whereas electronic media are, by far, advantageous in the memory capacity. This clearly indicates that both media are complementary and mutually dependent. Therefore, it is highly probable that paper media are still going strong in the future, hand in hand with electronic media, although the ratio between paper and electronic media can change, depending on the occasional demand of users.