Crêpe paper

Crêpe paper is tissue paper that has been coated with sizing (a glue-like substance) and then creped (creased in a way similar to party streamers) to create gathers.

Paper that is creped is produced on a paper machine that has a single large steam-heated drying cylinder (yankee) fitted with a hot-air hood. The raw material is paper pulp. The Yankee cylinder is sprayed with adhesives to make the paper stick. Crêping is done by the Yankee's doctor blade that is scraping the dry paper off the cylinder surface. The crinkle (crêping) is controlled by the strength of the adhesive, geometry of the doctor blade, speed difference between the yankee and final section of the paper machine and paper pulp characteristics.

Crêpe paper and tissue are among the lightest papers and are normally below 35 g/m².

The crêpe ratio reflects how much the paper has shortened during crêping. The figure is normally between 10 - 30%. Crêping is used to adjust the paper's stretch and thickness, both of which have a marked effect on softness and absorbency.

Crêping can also be applied to specialty papers, such as microcrêping in sack paper.

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