Our notebooks are made of 80gsm thickened double-gummed paper, the paper is smooth, highly impermeable, and will not bleed ink, such as ballpoint pens, pens, pencils, highlighters and so on can be assured that you can write on the paper. The work notebook's cover is thickened, and we have made it waterproof and anti-scratch treatment to protect the inner paper from curling and flattening, making it more wear-resistant and durable.