(1) Warning function: it is announced to the public that the products it sells have obtained patent rights and are protected by national laws, and no one may copy and sell them without permission;
(2) Differentiating function: Differentiating one's own products from similar products of other enterprises to avoid confusion among consumers;
(3) advertising function: by marking the patent mark or patent number, consumers can know that the product is superior to similar traditional products in terms of technical performance and use function, so as to improve consumers' trust in product quality and expand the market share of the product.