提高证券纸耐折度的研究

Study on Improving Folding Endurance of Security Paper

关键词:  证券纸  棉浆  打浆度  聚乙烯醇纤维  聚丙烯酰胺  耐折度

Key Words:security paper  cotton pulp  beating degree  PVA fiber  polyacrylamide  folding endurance

摘要:研究了棉浆打浆方式、棉浆与聚乙烯醇（PVA）纤维配比以及聚丙烯酰胺种类和用量对证券纸耐折性能的影响。结果表明，Valley打浆机和PFI磨两种方式混合打浆所抄证券纸的耐折度好于单独使用Valley打浆机时的，Valley打浆机打浆至34°SR后再进行PFI磨打浆，证券纸的耐折度分别在打浆度49°SR 和67°SR时出现峰值，为8794次和10981次。棉浆与70℃开始熔化的PVA纤维配抄，当PVA纤维用量为30%时，与未添加PVA纤维相比，证券纸的耐折度提高了约7%。添加不同种类聚丙烯酰胺，发现阴离子聚丙烯酰胺（APAM）在提高耐折性能方面效果显著，在其用量为0.4%时，与未添加APAM的相比，纸张的耐折度提高了28%。

Abstract:The effect of beating degree of cotton pulp, the mixing ratio of cotton pulp and synthetic fiber, the kind and dosage of reinforcing agents on the properties of the security paper were studied. It was found that there was great influence of beating on the fiber length and fibrillation of cotton pulp, they could influence the paper’s folding endurance. Combining the application of Valley beater with PFI refiner, the cotton pulp was beaten to 34°SR by Valley beater then furthen refined with PFI refiner, the best folding endurance were 8794 and 10981 times when the beating degree were 49°SR and 67°SR. Using 30% PVA fiber which begins to melt at 70℃ and 70% cotton pulp to produce the paper, the folding endurance of the paper only increased by about 7%. However, in comparision adding 0.4% APAM to the paper produced with 100% cotton fiber, the folding endurance of the paper increased by 28%.