Quantification of softwood,hardwood,and nonwood fiber content in packaging grade papers

摘要

This study determined percentages by weight of the fiber components in 15 papers commonly used to produce corrugating packaging in Spain.The papers are manufactured mainly from recycled raw materials.The percentages were determined by means of standard quantitative fiber analysis techniques and use of appropriate weight factors.Hardwoods were the major fiber component in all papers,except kraft liners,varying from 51% to 92% per weight.Kraft liners had greater softwood content (49%-69%) than hardwood,and the most plentiful softwood classes were pines.Douglas-fir was a contaminating fiber component (weight percentage less than 2%) in almost in every paper.Nonwood fibers,entering the papers through the recycling process,were a significant fiber component (2%-9%) in most of the papers,especially the waste-based papers (liners and flutings).Quantitative fiber composition reflects the differences in quality between the papers.Its usefulness could be further explored in the quality control of paper manufacturing for packaging.