Stone paper
Stone paper (Chinese石头 纸or石 科 纸) is a type of paper that from about 80 % calcium carbonate (limestone ) and 20 % organic polyethylene resin (HDPE ) is produced as a binder. The starting material for paper production normally not usable limestone games from existing limestone quarries are used, which are ground into a fine powder. Due to the composition, the density is about 60% higher than that of ordinary paper. In printing stone paper is commonly used in the 144 and 420 g/m2 grammage.
History
Beginnings of the use of mineral materials
The use of mineral materials for the production of printed matter goes back to Alois Senefelder, 1819 a patent for a " stone paper " was that he superficially coated with gypsum and lime powder, clay, oils and metal oxides. This paper has not proved suitable for everyday use. End of the 19th century, several patents have been awarded for stone papers, was where cardboard coated with a mixture of gelatin, glycerin, zinc white, and water and fixed with a solution of alum or formaldehyde. In a small extent such papers were used as transfer printing and lithographic plates.
Modern stone papers
The production of modern stone paper, which dispenses completely with the use of cellulosic paper, began in the late 1990s and was patented in over 40 countries. It was developed by the Lung Meng Tech Co., in Taiwan and is sold under names such as Parax Paper, Terraskin, ViaStone, Kampier, EmanaGreen and skirt Stock. In Germany, hard paper is marketed since 2010 and is mainly used for printing business cards, flyers and menu cards.
Properties and Uses
Stone paper has a number of advantages over cellulose paper from wood. It is oil -and water- resistant, food-safe, antistatic, flame retardant, not grainy and tear resistant. It burns with a clean flame without soot to calcium carbonate. Stone paper having a smooth surface, which has rather the properties of the coated paper and is therefore well suited for use in offset printing, UV-offset printing and digital printing.
It is suitable for inkjet and solid ink printers. Due to the percentage of bio- polyethylene, the paper from 65 ° C begins to thermally deform. The high temperatures in the fuser of laser printers / Copy all provide therefore a problem and stone papers are currently not suitable for this application. For the preparation of this paper to water, acids, bleach or wood are needed. Although it is not directly biodegradable, it decomposes under the influence of UV such as sunlight in the course of time. The LCA is evaluated from different sources differently; order of magnitude, only half is in the production of Rock Paper released carbon dioxide and energy needs. The production of Rock Paper is considered an important sustainable innovation in the regional circular economy.
Due to its characteristics stone paper is used as a special paper for the production of water-resistant land and special cards, notebooks, banners and posters. Due to the tensile strength of this paper is suitable for stable packaging, carrier bags and garbage bags. In addition, stone paper is used for the production of mechanically highly stressed catalogs, menus and manuals.