The Effect of Straw Fibers in Printing Papers on Dot Reproduction Attributes, as Realized by UV Inkjet Technology

Abstract

aPaper performance qualities strongly depend on the origin of cellulose fibers. Awareness of environmental issues and sustainable development has led to the increase in the use of recycled printing papers. Recovered fibers are often used as a substitute for virgin wood fibers in the production of certain types of papers. As recovered fibers cannot provide the same quality level of paper products as virgin wood fibers, alternative sources of virgin cellulose fibers need to be identified. The aim of this research was to analyze the printability of laboratory papers made of different contents of straw pulp. Therefore, the printing papers were formed using straw pulp of three different cereal species (wheat, barley, and triticale) and mixing them with recycled newsprint in different weight ratios. The printability of these laboratory papers was analyzed by classifying dot reproduction quality based on four dot reproduction attributes. Printed dot reproduction greatly affects the quality of reproduction in graphic products, as dots are the most important element in multi-color reproduction of texts and images. It was confirmed that laboratory papers containing straw pulp provide the same or even better dot reproduction quality than laboratory control papers formed only of recycled newsprint.

Assessment of the UV inkjet ink penetration into laboratory papers within triticale pulp and its influence on print quality

“…Figure 1 presents the process flow of laboratory paper production. 11 Laboratory paper substrates formed from recycled wood pulp (100%) were used as control samples (N) to compare the quality of papers with the addition of triticale pulp. In total, according to their composition, three different laboratory papers with triticale pulp (1NT, 2NT, 3NT) were formed.…”

“…In total, according to their composition, three different laboratory papers with triticale pulp (1NT, 2NT, 3NT) were formed. Their composition and some basic characteristics are presented 11 in Table 2.…”

“…10 To achieve optimal quality reproduction of graphic products it is necessary to be aware of paper substrate characteristics and its possibilities for printing with certain printing techniques. 11 Namely, after transferring ink onto the printing substrate, the ink spreads directly along the substrate fibres and penetrates in the bulk of the substrate. 12 The ink penetration into the printing substrate depends on the physical and chemical properties of the printing substrate and the inks used.…”

Determining the optical stability of printed laboratory substrates with wheat pulp after ageing treatment

“…Wheat straw as agricultural residue after harvesting was manually cut into 1 cm to 3 cm pieces and converted into semi-chemical pulp according to soda method [6]. Pulping conditions are presented in Table 1.…”

“…Fibre isolated from annual crop residues is a potential raw material for the pulp and paper industry due to many advantages of straw as a source of fibre; it is economical, obtained in abundant quantities and renewable [6]. On the other hand, there are still some shortcomings related to: fibre supply (fibre sources are harvested in a short period of time and are extremely voluminous, so large warehouses are needed, they are larger than wood which increases transportation and storage costs); production (a higher proportion of silica than wood makes a conventional chemical recovery system unsuitable, while appropriate production technology is not available and may become even more expensive than equipment used for wood); the demand stage of the use of non-wood fibres for pulp and paper production (the size of actual wood-free market is unknown) [7,8].…”