Research and Prospects of Color Business Printing Paper

Today, black-and-white printers have become popular in homes and offices. Color business printers have become the trend of development. Whether in the digital printing of business office or home, color printing is becoming more and more popular because color is a powerful, powerful and attractive expression tool with strong visual impact. . Especially in business, color can convey relevant information more clearly and effectively by emphasizing some important details. Some studies have pointed out that color can increase the readership of information transmission by 40%, improve people’s understanding by 75%, and increase their learning ability and interest by up to 75%.

In the black and white document and image output process, although the inkjet printer has many advantages, such as its own lower price, better image output, but also many deficiencies, such as a simple text printing effect is poor, the printing consumables have a short life cycle ,high cost. Compared with ink-jet printers, laser printers have obvious advantages in terms of text effects and printing costs, especially in terms of character accuracy, and print effects are comparable to those of factory printing; therefore, they are used in homes, businesses, and business offices. With booming development, black-and-white laser printers have firmly monopolized the document printing market and have shown a strong upward trend. The output media of the black-and-white laser printer is mainly paper. There are no special requirements for such paper, but it requires good paper formation, high whiteness, and flatness of the paper. Currently, computer paper and static electricity are used more often. Copy paper can also use plain printing and writing paper.

On the contrary, in the field of color printing, color inkjet printers are widely used due to their low prices and the use of water-based inks, which don't emit charged toxic particles during printing and endanger people's health. For color laser printers, despite their high image resolution and good color stability, the color density and fidelity of the print are difficult to match with color inkjet printing. Therefore, inkjet printers occupy a dominant position in color image output.

Inkjet printing technology entered the Chinese market for more than ten years, but it has developed rapidly. It has been widely used in office automation, digital photography, advertising production, computer graphics, CAD renderings, geographic information systems, remote mapping, and printing proofing. .

Based on the principle of color inkjet printing, the performance of printing paper for color ink jet printers is high, and ordinary ink jet printing paper cannot be used. On the contrary, the requirements for color laser printing paper are not very high. Only waterproof, moisture and weather resistance are required. The need for special color laser printing paper requires specialized production.

Classification of color business printing paper

Due to the continuous development of printing technology, a wide variety of printers are used for color documents and image output. According to the principle of color printing, full-color printing methods can be roughly divided into ink-jet printing, color laser printing, sublimation printing, and thermal printing. . Correspondingly, according to the output mode and output requirements of the color printing apparatus, the color business printing paper can be subdivided into color inkjet printing paper, color laser printing paper, thermal printer paper and thermal sublimation printing paper.

2.1 color inkjet paper

There are many types of ink jet paper, but the color ink jet paper is different from ordinary paper. The color ink jet paper needs good ink absorption and ink fixation, can absorb water-based ink, and can not spread the ink to the periphery. In order to completely maintain the original color and clarity. The printing performance of the color ink-jet printing paper is mainly determined by the structure and function of the ink-absorbing layer, not only to quickly and evenly absorb the ink, to prevent the occurrence of blemishes, capillary phenomena and strikethrough during the ink drying process, but also to ensure good Print quality, color reproduction, good dot roundness, high printing density, high color density and color intensity, especially high-gloss paper-grade color inkjet printing paper, require clear print images, printing density High, the level of silver salt photos can be achieved in terms of vivid colors, detail levels, and color fastness.

Color ink-jet printing paper can be divided into ordinary color ink-jet printing paper, matte coated color ink-jet printing paper and glossy cloth color ink-jet printing paper, in which gloss-coated color ink-jet printing paper has the best performance, and the price is also The highest, with a high gloss, high whiteness of the paper, good ink absorption, printing image hierarchy, color saturation, strong color expression, similar to the photo-level image effect, but its absorption of liquid speed and With reduced water resistance, it is the highest grade inkjet printing paper and is widely used in the commercial field.

2.2 Color Laser Paper

Color laser printers are low-cost, high-efficiency, high-quality color print output devices. However, compared with color inkjet printers, color laser printers print images are not very good performance in the overall color saturation of the picture is dark, less transitional levels, and more close to prints than silver salt photo-level image effects. In addition, a layer of silicone oil is always attached to the print surface of the output of a conventional color laser printer. The reflection of the entire screen is strong.

The imaging principle of a color laser printer is similar to that of a black and white laser printer. Laser scanning is used to form a charge latent image on a toner cartridge. Then the toner is adsorbed and the toner is transferred to the printing paper, except that the monochrome laser printer has only one type. Black toner, while color laser printers use toners of yellow, red, cyan, and black colors. Based on this, the performance requirements of color laser printing paper are not very high, as long as there is high whiteness, the paper surface is flat, the difference between the two surfaces is small, and the loss of the printing equipment is less. However, if it is to be used for the production of high-end renderings, tenders, exquisite brochures, and certain special uses for waterproofing and moisture-proofing, the base paper should be processed to obtain good color printing effects and corresponding functions.

2.3 color thermal paper and dye-sublimation printing paper

Thermal-sensing printing is the use of specially-treated heat-sensitive special-purpose printing paper, an advanced technology that incorporates silver salt photography and thermal recording. The printing process does not require ribbon and ink. The printing paper itself contains yellow (y), magenta (M), and blue (C) dye layers. When the print paper is exposed to the thermal energy of the print head and the UV fuser lamp, the color is released.

Sublimation printing is also the use of heat-sensing technology. The principle is to "move" color dyes to the print media by some means to form brilliant images. Dye sublimation transfer printing uses special paper output, the output is exquisite and exquisite, and the quality can be comparable to silver salt photos. Although sublimation printing photos works well, due to its slower printing speed, higher requirements are imposed on printing paper, and printing costs are also very high, which makes it difficult to gain popularity in the business field. $Page break $

Study 3 Color ink-jet paper

Survey data show that in recent years, with the advancement of color inkjet printing paper manufacturing technology, quality color inkjet printing paper is getting higher and higher, and the price is falling, making color inkjet printing technology for business and home office The main methods of document and image output accounted for 70% of the color business printing market, and continued to grow at more than 40% growth rate. The quality of color ink-jet printing paper is mainly determined by the performance of the ink-absorbing layer, especially the paper-grade color ink-jet printing paper, which requires the vividness, saturation, detail level, sharpness and color of the printed image. Both reduction and color fastness can reach the level of color photo paper. In order to achieve high-quality image effects, color ink-jet printing paper should have the following characteristics: It can absorb ink evenly and quickly, without bleed, smudging, and blemishes; ink dots have a high degree of roundness and sharp edges. High dot density, high image resolution, good color fastness, good water resistance, light resistance, abrasion resistance, and preservation of image and text; good color reproduction, high saturation, high color density and Color intensity.

3.1 The research status of color inkjet paper at home and abroad

The study of color ink-jet printing papers abroad started earlier, and related reports and patents were relatively numerous. The research content mainly focuses on the inkjet materials, Xu cloth technology, Xu composition and printed images. For example, Hyun-Kook and Margaret et al. have conducted more in-depth research on color ink-jet printing papers. Their research suggests that (1) conventional coating pigments replace a part of alumina and silica to reduce production costs; (2) gas-phase oxidation Effects of Si on the structure and print quality of the Xu layer; (3) Effects of silica and alumina on the structure and print quality of the Xu layer; (4) Effects of the chemical properties and particle size of the pigment on the structure of the Xu layer and Xu Layer structure on the print quality and so on. (5) Study of metal oxides in glossy inkjet paper coatings. In addition, there is Rich

YR et al. studied that the addition of cationic additives has a great influence on the properties of the material, and increases the viscosity, yield stress, and elastic modulus of the coating. Cawthorne

J. et al. made a study on the use of modified china clay and silica to produce matt inkjet paper. Boylan J.R. studied polyvinyl alcohol as an adhesive for inkjet paper. Jopson

RN researched adhesive modification and its application in blade coating production inkjet paper. A.Hladnik used a self-developed print test form to measure print image quality, and used the main component analysis method (PCA) to conduct research on the quality evaluation of inkjet paper. Jonckherree

E. and Mabire have made studies to improve the water resistance of matt and glossy inkjet paper; KatriVikman has studied the fastness properties of coated inkjet paper; Henry

Wilhelm discussed the lightfastness of ink jet printed color photos and traditionally washed color photos.

However, it is only in recent years that domestic research has focused on coating inkjet paper. At present, the main institutions engaged in the research of color ink jet printing paper mainly include Hunan Paper Research Institute, South China University of Technology, Shandong Institute of Light Industry, Northwest University of Science and Technology, Nanjing Forestry University and Tianjin Yuanda Materials Co., Ltd., etc. The research content mainly includes the analysis of color ink-jet printing paper, the properties of the coating layer, the coating composition, and the specialty chemicals. Most of them focus on silica coating pigments, application of coating chemicals, etc., and there are fewer experimental studies conducted. Existing research includes: research on the layer structure and sheet properties of high-gloss color ink-jet printing papers, research on ink-jet printing paper coatings, and color inkjet on the Beijing Pulp and Paper Research Institute and the Hunan Paper Research Institute. Development and research of printing paper.

3.2 color inkjet paper coating research

Studies have shown that the microscopic and macroscopic pore structures of coatings have a great influence on the print quality of color ink jet paper because most of the ink composition is water (2%-5% of dyes or pigments, 2%-5% of the surface Active Agents and Additives, 30% Humectant, 65% Water. The coating must be quickly absorbed by the ink in order to fix the ink and prevent water from penetrating into the paper base so as not to affect the print quality. In conventional coating pigments such as kaolin, calcium carbonate, and titanium dioxide, pores that are conducive to liquid absorption (.2-0.4um) have a small effective volume fraction and facilitate liquid flow (0

.OZ-0

.04um) has a narrow pore diameter and is unsuitable for use as a pigment for color inkjet paper coating. Due to the large oil absorption of silicon and aluminum oxides (20. g silicon oxide oil absorption 200-350 g), large BET surface area (250-600 m2/g), and the formation of a high porosity similar to the sponge-like In the network structure, when the ink contacts the silicon-containing layer, the porous layer quickly absorbs the ink solvent, while the dye and the colorant are fixed on the surface of the coating, showing a good optical printing density, so it is more suitable for spraying. Ink paper coating pigment.

According to the coating ink-absorbing mechanism, the ink-absorbing coating of color ink-jet printing paper can be classified into a swelling type and a void type, or a resin type and a pigment type. The swellable ink-receptive coating is mainly composed of some macromolecules capable of absorbing water and swell, such as gelatin, polyvinyl alcohol, polyvinylpyrrolidone, PT-propyl cellulose, and the like, and the resin undergoes slight swelling after receiving the ink. , Stick ink, absorb ink, but the ink drying speed is slow, poor water resistance; and void type ink-absorbing coating is composed of a pigment with a microporous structure or can form a porous structure of the material, such as amorphous oxidation Silicon, alumina, etc. form an internal pore structure to achieve rapid absorption and color fixation of ink droplets.