Most banknote papers are made from cotton fibers. Generally, banknote papers are much more durable than commercial printing papers.
In the production of paper, various polymeric additives are used in the wet-end of paper machines in order to improve the retention of pigments and fine materials, the formation and drainage properties of the paper web etc.
Guar gum is added to the pulp suspension at the suction side of the fan pump just before the sheet is formed on either a fourdrinier or cylinder machine. Along with the lignin removed in the pulping process, much of the natural hemicelluloses are removed. Guar gum replaced and supplements these hemicelluloses in paper bonding with many advantages, which include improved sheet formation with a more random distribution of pulp fibers.
The flocculation of negatively charged fine particles by cationic PAM(C-PAM) occurs by the adsorption of the PAM chains onto the particle surface. Thus, charge neutralization becomes a major mechanism, where the C-PAM will locally reverse the particle surface charge. Also, C-PAM is known to neutralize the charge on fibrous substrates through a patching mechanism, which is established in papermaking and in sludge dewatering.
Anionic PAM(A-PAM) is widely used as retention aids and dry strength resins. The most basic rule is that the furnish must have a suitable cationic source to serve as anchoring points for the anionic retention aid. Such materials as PAE, poly-DADMAC and cationic wet strength resins are especially effective in this role as promoters of the retention aid.
Carboxymethyl cellulose(CMC) has been used as a dispersing or deflocculating agent in the paper industry. It has been shown that CMC has the ability to disperse the pulp fibers and promote inter-fiber bonding.
In this study, various properties of cotton handsheet were measured to solve the problem of deformation while storing guar gum(natural polymer) and to improve strength and retention by synthetic polymers(A-PAM, C-PAM, CMC).

The results of this study were summarized as follow :

1. As the results of mechanical properties, cotton handsheet with A-PAM 0.2% was the best tensile index and folding endurance.

2. Retention of fines and fillers in pulp slurry with A-PAM 0.2% and 0.3% were more excellent than those with guar gum.

3. After thermal treatment, cotton handsheet with A-PAM 0.2% and 0.3% had good mechanical properties and bursting index and folding endurance of cotton handsheet with A-PAM 0.3% was similar to those of guar gum.

4. After thermal treatment, yellowness loss of cotton handsheet with synthetic polymers(A-PAM, C-PAM, CMC) was lower than those of guar gum.

5. The oxidation index of cotton handsheet with A-PAM 0.3% was lowest. Therefore, its durability was higher than other additives.