Paper-making reconstituted tobacco preparation method and method for improving coating liquid absorbability of paper-making reconstituted tobacco substrate

The invention provides a paper-making reconstituted tobacco preparation method and a method for improving coating liquid absorbability of a paper-making reconstituted tobacco substrate. The paper-making reconstituted tobacco preparation method includes steps: 1) after extracting with an extracting agent, performing solid-liquid separation to obtain tobacco insoluble matters and tobacco extract liquid; 2) subjecting the tobacco insoluble matters to pulping, and performing net forming and pressing to obtain a wet substrate; 3) subjecting the wet substrate to drying, coating of bicarbonate and drying to obtain a substrate; 4) subjecting the tobacco extract liquid to refining concentration to obtain coating liquid; or adding organic acid after refining concentration to obtain the coating liquid; 5) coating the substrate with the coating liquid, and drying and slitting to obtain reconstituted tobacco. Liquid absorbability of the substrate is improved by thermal decomposition action of bicarbonate; preferably, coat