若是橡胶和金属的连接，模具表面的保护就显得尤为重要了。橡胶和金属的粘结剂不管接触到什么物质都很有粘性，因此就可能粘附于模具表面，从而导致模具结垢。时间长了会在无防护的模具表面留下垢污。
If the connection between rubber and metal, the protection of die surface is particularly important. Rubber and metal binders are sticky no matter what they touch, so they may adhere to the surface of the die, resulting in scaling of the die. Over time, dirt will be left on the unprotected die surface.
要预防这种情况，脱模剂必须能形成一层结实的保护膜，从而延长模具在使用半永久性脱模剂时的运行时间。其材料在成品脱模后都有可能在模具表面留下多余的垢，如果长时间累积的话，脱模便捷性就会降低。
To prevent this, the release agent must be able to form a strong protective film, thus prolonging the running time of the die when using semi-permanent release agent. The material may leave excess scale on the surface of the die after the finished product is demoulded. If accumulated for a long time, the demoulding convenience will be reduced.
如果在橡胶材料开始粘附模具表面之前不阻止余垢的累积，最终导致产品品质下降，报废率增大。
If the accumulation of residual scale is not prevented before the rubber material begins to adhere to the surface of the die, the product quality will eventually decline and the scrap rate will increase.