Which paper is used as a reference for cationic size?

zed, uncoated paper. The white, uncoated paper was u ed as the reference. Each size type was applied in the pH range, that i best for that type. Over the whole concentration range better sizing values were obtained wi h the cationic size.The cationic sizes contain protonated or quaternized amino group

Why is cationic surface size preferred?

Often a cationic surface size is preferred because of its higher sizing efficiency, but with recirculation of the size-press solution and contamination from the wet end the efficiency can be decreased. An anionic trash catcher such as polyaluminium chloride

What is a Typical sizing specification for a fine paper?

A typical sizing specification for a plain fine paper is a Cobb(60 s) value of 20-25 g m-2 or a HST value (80% reflectance, 1 % formic acid, naphthol green ink) of 200-300 s, although examples can be found of harder and softer sized sheets. The HST value is more sensitive to the effects of the surface treatment.

What are cationic sizing agents?

olymer sizing agentsThe cationic sizes are generally stabilized with protonated or quat rnized amino groups. Their high affinity for anionic substrates means that their effectivity is assured, even in papers with high concentrations of anionic interfering substances, e.g. in the case of recycling and wo

What is the charge equivalent weight of a paper additive?

all paper additives. It has a charge equivalent weight of 1500 g/ eq for anionic and 1800 g/ eq for cationic groups, which is a factor of 5 and3 respectively higher than so that the amphoteric character is appr

How do cationic surface sizing agents work?

ion of acid or base.Usually, surface sizing agents are designed in the way, that they set up their o timal pH themselves.Thus, for example, cationic surface sizes are generally adjusted to an acidic pH range, so that, on their addition, the pH of the starch liquor is automatically shifted in