This machine coats wax onto paper.
Generally, a gravure roll coater, reverse roll coater and so on are used.
The gravure roll coater draws the wax with a gravure roll, scrapes off the excess wax with a doctor, and coats the wax onto paper.
In the case of the reverse roll coater, the coating roll is in the reverse direction of the paper, and the amount of coating can be accurately controlled when it is descending too, so processing can be performed regardless of the amount of coating.
In another machine structure, paper is passed through a tank of melted wax to impregnate (soak) the paper, and then the wax is squeezed out in a press roller.
Paraffin wax is a petroleum-based wax that belongs to the natural wax category (animal-based wax such as beeswax, whale oil, etc., and plant-based wax such as Japan tallow, etc.).
This is manufactured through making lube-oil distillate by means of distillation under reduced pressure, and then performing dewaxing, deoiling and refinement.
Paraffin wax is a hydrocarbon compound mainly composed of straight-chain hydrocarbons (n-paraffin) with a carbon number of 20~36.
Functions and Uses of Wax Paper
Wax paper is expected to have oil-proof, waterproof, moisture-proof, and rust-proof properties.
When used in food packaging, it can preserve the freshness of bread, caramel, candy, frozen foods, meat, fish, vegetables and so on; and when used with machine components, it can prevent rusting by guarding against infiltration of moisture.
Moreover, by using wax that is blended with insect repellent and anti-microbial agents, the resulting paper can be used for bags that are placed over fruits during the growth stage. The texture of wax paper is characterized by a unique glaze and permeability that also earns it attention for use as chic wrapping paper, envelopes and other stationery with an antique feel.
Waxing in SAN-AI
Wax can be applied to the base paper in the ratio of 17g/㎡~140g/㎡, enabling the processing of various products ranging from thin to thick paper.
However, because SAN-AI adopts the method of coating wax by immersing paper, so the quality of the base paper determines the applied quantity of wax.
We can also perform single-side coating without immersing. The finished products are wound into rolls.
Since we mainly manufacture food wrapping paper, the work is conducted in an insect-repellent environment (room), while flat paper processing is also conducted in a separate room.