| 摘要 |
PURPOSE: A coating liquid for the office work and its preparation method are provided, wherein the coating liquid is used to coat the surface of letters or numbers written on a document for preventing the forgery or alteration of the document. CONSTITUTION: The coating liquid is prepared by mixing a vinyl acetate resin powder and methyl alcohol in the ratio of 1:20 to prepare a vinyl acetate resin solution; mixing ammonium chloride and water in the ratio of 1:5 and heating the mixture to prepare an ammonium chloride aqueous solution; mixing the vinyl acetate resin solution, the ammonium chloride aqueous solution, a water-soluble melamine resin, glycerin and sodium silicate in the ratio of 30 : 1 : 30 : 9 : 30, pouring the mixture a rotation pulverizer and mixing and pulverizing the mixture for 24 hours to prepare a mixture solution; filtering the obtained mixture solution; and transferring the filtered mixture solution to a charge tank and charging a coating liquid container with the mixture solution. |
