Novel Silicate 'Fibrous Fillers' and Their Application in Paper

摘要

Fillers are generally an integral part of paper products. Most conventional/commodity fillers are of small size, lowrnaspect ratio, and high bulk density. These fillers cause interruption in inter-fiber bonding, resulting in the loss ofrnsheet strength. Although the price of these fillers is attractive at $120/ton to $400/ton, their use is limited to ～15%-rn～18%. Some specialty fillers are of large particle size and high surface area. These specialty fillers are veryrnexpensive: ～$2000/ton and higher. In the meantime, the industry, facing various challenges from electronic mediarnand other alternate material, is looking for ways to reduce manufacturing cost and reduce energy consumption.rnFillers are one good way to reduce cost and improve paper performance. Thus the industry is looking for arnbreakthrough in filler technology which will provide unique functionality and provide high benefit to cost ratio.rnGRI has developed a series of rather unique calcium and silica-based filler, collectively referred to as "fibrousrnfillers". There are two main products. One product is referred to as silicate nano-fibers [SNF] or ultra-high opaques,rnand the other is silicate macro-particles [SMP] or ultra-high bulk. The unique characteristics of these "fibrous filler"rnare high aspect ratio (>1:10 to 1:50), and low bulk density with fibrous structure. These novel "fibrous fillers"rnimpart extraordinary sheet properties and end-use performance. The silicate nano-fibers simultaneously give higherrnoptical properties, bulk, smoothness, porosity and stiffness properties. The silicate macro-particles give ultra-highrnbulk and almost 100% better stiffness than conventional PCC.rnBecause of these unique characteristics, it is possible to manufacture paper containing 40% + "fibrous filler", whilernmaintaining or improving critical paper properties. This results in the reduction of fiber consumption, replacementrnof expensive functional fillers like titanium dioxide, or reduction in basis weight, eventually resulting in substantialrncost savings. The use of "fibrous filler" is expected to save approximately 1.0 trillion BTU of energy per year.rnThus in the future, it is possible the paper industry will have its own on-site "fibrous filler" mill with or without arnpulp mill to feed the paper machines. In effect, the "fibrous filler" technology will cause a major paradigm shift.