▎ 摘　　要

NOVELTY - Coating material comprises cement, nano-modified material and hydrophobic agent, where the cement is portland cement, and the mass ratio of nano-modified material to the hydrophobic agent is (1-3): (2-3). USE - The coating material is useful for improving water resistance and mechanical properties of cement-based materials (claimed). ADVANTAGE - The material: has improved compactness, mechanical properties and durability of cement-based coatings, and high hydrophobicity while having ideal mechanical properties. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparing coating material, comprising (i) mixing cement, auxiliary cementitious material, nanometer material, binding agent and fine aggregate to obtain mixture A, (ii) mixing water reducing agent, hydrophobic agent and part of deionized water to obtain mixture B, (iii) mixing remaining deionized water and defoamer to obtain mixture C, and (iv) firstly mixing mixture A and mixture B, and mixing mixture C.