Abstract: A resin-coated steel sheet having excellent properties such as electroconductivity, electrostatic earth property, fingerprint resistance, corrosion resistance, solvent resistance, workability, press formability, workability at multi-processed part, electromagnetic shielding property, adhesion, and heat release property, a resin composition and a surface treatment composition therefore are provided. The resin-coated steel sheet comprising a base steel sheet; and a resin-coating film formed of a resin composition on the surfaces of the base steel sheet, the resin composition comprising a main resin/a melamine-based curing agent composition, a pigment, a flatting agent and at least one of a fingerprint-resistant additive and an electroconductive additive is provided.

Abstract: A Cr-free steel sheet includes a Zn-based electroplated steel sheet, a Cr-free layer which is formed by a Cr-free treatment liquid coated on the steel sheet, the Cr-free treatment liquid containing silicate of 3 to 40 parts by weight, silane of 0.5 to 10 parts by weight, titanium compound of 0.2 to 8 parts by weight, binder resin of 10 to 50 parts by weight, the binder resin being selected from the group consisting of urethane resin, epoxy resin and a combination thereof, and phosphoric ester of 1 to 5 parts by weight based on the Cr-free treatment liquid of 100 parts by weight, and a resin layer which is formed by a resin treatment liquid coated on the Cr-free layer, the resin treatment liquid containing melamine resin of 3 to 25 parts by weight, colloidal silica of 10 to 20 parts by weight, metal powder of 5 to 40 parts by weight, and phosphoric ester of 1 to 5 parts by weight based on phenoxy resin of 100 parts by weight.

Abstract: A chrome free composition for metal surface treatment and a surface-treated metal sheet can provide excellent characteristics of high conductivity, corrosion resistance, alkali resistance, and high temperature and humidity resistance. The composition includes a vinyl based binder resin, an acryl based binder resin, and a solvent. In the vinyl based binder resin, a corrosion-resistant inorganic material is combined, and an amount of the vinyl based binder resin is in a range of 10 weight % to 70 weight % with respect to a total solid content. In the acryl based binder resin, a corrosion-resistant inorganic material is combined, and an amount of the acryl based binder resin is in a range of 15 weight % to 75 weight % with respect to the total solid content. An amount of the corrosion resistance inorganic material is in a range of 3 weight % to 25 weight % with respect to a total solid content.