Coating lubricant application

The application of paper coating lubricants dates back to the beginning of this century. At that time, the adhesive for paper pigment coating was mainly animal glue or casein, and the solid content of the coating was very low. Although these adhesives have good adhesion and excellent water retention performance, the film formed by them is very brittle, so it is necessary to add an additive that can improve the folding and bending resistance of coated paper and board. These additives also improve the fluidity and equalization of wet coatings. This additive became the paper lubricant.

Coating lubricant function

The function of the lubricant varies with the different paper types and the differences in the production habits of the paper mill. Sometimes the fluidity of the coating and some properties of the coated paper (such as gloss, smoothness, oil absorption, surface strength, etc.) are used to evaluate the performance of the lubricant. Some categories of lubricants have special functional characteristics, such as "viscosity adjustment characteristics", "improved dry friction resistance", "improved wet adhesion", "improved wet friction resistance", "ink gloss and impermeability", "plastic", "folding resistance" and "improved gloss", etc.

The ideal lubricant should show the following properties

(1) lubricate the paint and improve its flow characteristics;

(2) Ensure a smoother coating;

(3) Improve the gloss of the coated product;

(4) Improve the printability of paper;

(5) Reduce the cracks and peeling of the coating when the paper is folded;

(6) Reduce or remove powder in super calender.