Blue and white double-sided coated cardstock is made from fully chemically bleached wood pulp, with a base weight of approximately 150 grams per square meter or more. Uncoated ones are called sika paper, and those coated on both sides are called copper sika. Main uses: Xika paper is mainly used for business cards, wedding invitations, postcards, cards and data cards. Copper sika is mainly used for paper boxes that require exquisite printing, such as book and magazine covers, postcards, cards, wedding invitations, product tags, cosmetics and medicines.