| Tissue wrapping paper is mainly used in packaging for footwear, clothing, and wine and so on. In our country, the raw material of tissue wrapping paper is mainly bleached wood pulp which is mostly imported from abroad and consequently increases the production cost. It is imperative to develop new materials and apply new technology to produce tissue wrapping paper. Secondary fibers are used to produce tissue wrapping paper at high speed paper machine instead of part of the original fiber, which has great significance on improving the shortage state of wood fiber materials in our country, and reducing production cost. Since, secondary fibers have many weakness, such as serious horny, poor fiber performance, high content of fines, poor filtering performance, and high content of stickies, low wet paper intensity, big adhesive power, and great amount of anionic trash. Therefore for secondary fibers, beating and mixing with wood pulp, addition of filter aid and wet strength agent, and optimizing the sequence of additive addition are necessary for improving fiber performance, drainability, wet strength and additives efficiency. Based on the above background, this paper will focus on original materials and addition of papermaking additives. The impacts of beating and mixing, addition of agents of filtering aid and wet strength on papermaking properties were studied in this paper, and it will provide theory guidance to the actual production of tissue wrapping paper with second fibers in mills.It was analyzed that the fiber properties of the deinking pulp (DIP) and needles bleached kraft pulp (NBKP), which are used as the raw materials. DIP and NBKP were beaten at the beginning; it was also analyzed the influence of fiber properties, the pulp drainability, the wet paper strength and adhesion power, the paper strength by beating. Then the best beating degree is found in deinking pulp and bleached kraft pulp for the production of wrapping paper. Results showed that the fiber properties of NBKP are superior to deinking pulp. Bleached kraft pulp fiber has longer fiber length and fewer fines. The average fiber length of NBKP and DIP were 2050 μm and 801 μm, and the amount of fines content in length are 36.1% and 16.8% respectively. Beating could cut down fiber to different extent, increase fines, and reduce pulp drainability. However, beating could increase the rate of fiber broom, and reduce the degree of curl and kink fiber, benefitially decrease wet web adhesion, and improve the dry and wet paper strength and increase the paper making performance. When the beating degree of NBKP and DIP are 60°SR and 55°SR, respectively, NBKP has the highest tensile strength; DIP tensile index and bursting index were increased by 135% and 137% than the original data, how ever, tearing strength has tend to decrease. When the beating degree of NBKP and DIP are higher than 60°SR and 55°SR, respectively, over-beating will negatively impact on the performance of the slurry sheet-forming. Moreover, the static filtering time was in a sharp increase. The static filtering time of NBKP and DIP at 60°SR and 55°SR were 11.7 s and 8.1 s respectively, increasing by 208% and 89% compared with the initial values. NBKP wet paper tensile index and tensile plot did not increased any more, and DIP wet paper tensile index did not increased much. Meanwhile the length and aspect ratio of the fiber would be declined rapidly. The rate of decline of NBKP fiber length at 60°SR was 11.1%, DIP fiber length decline at 55°SR was 18.5%; NBKP and DIP fiber aspect ratio was 62.6 and 35.0 respectively, decreasing by 10.6% and 20.5% compared with the initial value. Therefore, the best beating degree of NBKP and DIP was (60±2) °SR and (55±2) °SR respectively on wrapping tissue paper production.It was studied that the impact of deinking pulp and bleached kraft pulp mixing ratio on fiber properties papermaking properties and tissue paper performance. The results showed that adding a little native sulphate pulp improved the performance of papermaking and paper strength properties significantly, and reduced wet paper adhesion, and improved the performance of papermaking slurry significant.. When the mixing ratio of DIP and NBKP was 80:20, the tissue paper breaking length, bursting index, tearing index and stretch wet paper tensile index were increased by 25%,43%,21% and 37%, respectively; Wet paper tensile index and stretch product in tissue paper were increased by 2.4 times and 4.0 times and wet web adhesion decreased by 2.8%. compared with 100% DIP, as raw materials. Considering the production cost, the mixing ratio of DIP and NBKP at 80:20 were selected as the pulps for wrapping tissue paper production.It was analyzed that the influence of wet strength agent PAE on slurry charge, papermaking performance of pulp and paper strength properties.The results showed that adding cationic PAE resin can rapidly reduce dissolve charge and surface charge of the slurry, and improve the slurry charge environmental effect remarkably. When the dosage of PAE is about 0.6%, the paper absorption index and breaking length growth trends have begun to slow. Paper breaking length is 4.15 km, and paper absorption index is 1.22 J·g-1. Thus, optimal dosage of PAE is 0.5%～0.6% in secondary fibers producing wrapping tissue paper. Under this condition, wet paper tensile index, stretch wet paper product and S/A (stretch wet paper product-adhesion) ratio is about to reach the highest level,0.54 N·m·g-1、0.03 N·m and 257 separately.It was studied the influence of retention and drainage aids cationic starch and their synergistic effect on slurry charge, pulp papermaking performance, and paper strength properties. The results showed that cationic starch (CS) can be added to improve the pulp charge environment. E.g. when the addition amount of CS is in 0.5%,, dissolving pulp charge CD values and the absolute value of the Zeta potential were 27.7 μeq·L-1 and 144 mV, respectively, decreasing by 26.9% and 11.1% compared with their initial values); the retention rates and pulp drainability, while the wet paper into the paper tensile strength and breaking length also has improved to some extent. The addition amount of CS is about 0.7% has the highest efficiency on improving pulp drainability, and therefore it is he optimal dosage for tissue wrapping paper production. This paper also observed the effects of adding sequence of wet strength agent and retention and drainage aid on synergistic effects of each additive. The study showed that with dual retention aid CS/APAM, APAM can significantly strengthen CS retention and drainage effect. Adding PAE before APAM can get better synergy effects and avoid invalid additives efficiency simultaneously. |
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