Polyvinyl alcohol (PVA) is a water-soluble synthetic polymer that is widely used as a surface sizing agent in the paper and paperboard industry.
In different paper and paperboard, PVA for surface sizing has different advantages.
1. Kraft paper liner paperboard
To improve the abrasion resistance, surface gloss and printing gloss.
2. Jute liner paperboard
The main raw material of jute liner is waste paper. After sizing with polyvinyl alcohol, the strength of paper can be improved. The concentration of polyvinyl alcohol should be properly increased for inferior waste paper.
3. White newspaper
For the purpose of improving the printing gloss, color generation of ink and IGT surface strength.
4. Oil resistant paperboard
In order to make the cardboard used for the thick paper box of fatty food oil resistant.
5. High quality paper
To improve IGT surface strength and printing adaptability.
6. Back Sizing of Single sided Coated Paper
The coated paper with only one side coating is very easy to curl. In order to prevent this kind of curl, glue should be applied on the back.
7. Paper for banknotes
Money paper is easy to be damaged in circulation, so it is required to have folding strength and high water resistance. At the same time, in order to install the automatic counter, it is also necessary to have proper rigidity.
8. Undercoating of coated base paper
In order to make the coated color dissolve evenly on the paper, the coated surface is smooth, and the strength of pigment adhesive on the paper is restrained.
9. Oil resistant paper
Give play to the oil resistance of polyvinyl alcohol. It can be used for the surface of waterproof paper and paper for packaging fatty food.
10. Cellophane
Good transparency and oil resistance after coating.
11. Carbon base paper for carbon
When the organic solvent dispersion of carbon black is coated on the paper, polyvinyl alcohol can be primed on the base paper to prevent the solvent from saturating the paper and obtain a uniform coating layer of carbon black.
12. Stripped paper
There are two situations. One is to apply polyvinyl alcohol in a single coat, making use of the peeling property of polyvinyl alcohol itself. The other is to use silicon (oxygen) resin manufacturing materials to peel the paper. In order to prevent the penetration of expensive silicon (oxygen) resin and reduce cost, polyvinyl alcohol can be coated at the bottom.