The reason why the welded Himei waterproof tile can achieve the anti-penetration effect is that the hot air welding re-melts the molecular structure at the seams of the coiled material through high temperature to form a continuous, seamless overall layer. This process eliminates the gaps and weaknesses at the seams, making the welded coiled material extremely tight and consistent, thereby effectively preventing moisture penetration and ensuring the reliability of waterproof performance.