Abstract: The present invention relates to a press-heating gas grafting hydrophobization apparatus, and a hot water-resistant paper and an oil-absorbing paper manufactured using the press-heating gas grafting hydrophobization apparatus. In the press-heating gas grafting hydrophobization apparatus according to the present invention, since a non-air-permeable dryer belt is provided surrounding and pressing a drying roller to prevent dissipation from a base material of a fatty acid chloride vaporized by the drying roller, the press-heating gas grafting hydrophobization apparatus has an advantage of improving efficiency of a gas grafting reaction. Therefore, by using the press-heating gas grafting hydrophobization apparatus according to the present invention, the reaction amount of fatty acid chloride per unit area can be remarkably improved.

Abstract: Using the sympathetic printed-matter according to the present invention, a hidden content can be visualized just by wetting. Therefore, it is possible to remove necessities of the sympathetic ink and a special material such as reagent or equipment for visualizing hidden contents. In addition, since the hidden contents disappear by removing water from the sympathetic printed-matter, the sympathetic printed-matter can be used repeatedly. Using the reading confirmation portion, whether or not the sympathetic printed-matter has been read by any other person can be easily determined. In the sympathetic printing method according to the present invention, a hydrophobic substrate can be formed using an existing gas grafting facility, and an ester hydrolase composition and the reading confirmation portion can be formed using an existing printing method. Therefore, a large amount of sympathetic printed-matters can be produced inexpensively and efficiently.