Abstract: Provided is a chromium-free, low-temperature curable, metal-surface treatment composition comprising 5 to 30 parts by weight of a silane compound having an epoxy group and a silane compound having an amino group or a hydrolytic condensate thereof; 0.1 to 5 parts by weight of a vanadium compound; 0.1 to 5 parts by weight of a magnesium compound; 1 to 10 parts by weight of organic/inorganic acids; 0.05 to 2 parts by weight of a crosslinking accelerating and coupling agent; 0.01 to 1 part by weight of an antifoaming agent; 1 to 2 parts by weight of a wetting agent; and the balance of water and ethanol, based on 100 parts by weight of the total solution. In addition, a steel sheet coated with the above-described metal-surface treatment composition is low-temperature curable and provides anticorrosiveness while containing no chromium components.

Abstract: A spangle-free, hot-dip galvanized steel sheet, and a method and device for manufacturing the same. The hot-dip galvanized steel sheet is characterized in that a solidified zinc crystal of hot-dip galvanized layer has an average crystalline texture particle diameter of 10 to 88 ?m and there is no solidification traces of dendrites upon observing under a microscope at a magnification of 100×. The method comprises dipping a steel sheet in a bath of a zinc-coating solution containing 0.13 to 0.3% by weight of aluminum; air-wiping the steel sheet to remove an excess of the coating solution; spraying water or an aqueous solution on the air-wiped steel sheet, using a steel sheet temperature in the range of a hot-dip galvanization temperature to 419 ° C. as a spray initiation temperature and using a steel sheet temperature in the range of 417 ° C. to 415 ° C.

Abstract: Provided is a chromium-free, low-temperature curable, metal-surface treatment composition comprising 5 to 30 parts by weight of a silane compound having an epoxy group and a silane compound having an amino group or a hydrolytic condensate thereof; 0.1 to 5 parts by weight of a vanadium compound; 0.1 to 5 parts by weight of a magnesium compound; 1 to 10 parts by weight of organic/inorganic acids; 0.05 to 2 parts by weight of a crosslinking accelerating and coupling agent; 0.01 to 1 part by weight of an antifoaming agent; 1 to 2 parts by weight of a wetting agent; and the balance of water and ethanol, based on 100 parts by weight of the total solution. In addition, a steel sheet coated with the metal-surface treatment composition of the present invention is low-temperature curable and is capable of securing anticorrosiveness even without containing chromium components.

Abstract: An aqueous silver-containing solution comprising nano-sized silver particles wherein silver (Ag) particles having a particle diameter of 1 to 20 nm have a concentration of 200 to 100,000 ppm, the pH of the solution is maintained in a range of 6 to 8.5, and based on the weight of the silver-containing solution, an amount of a stabilizer as an impurity is in a range of 0.5 to 1.5% by weight, an amount of anions of a silver salt as another impurity is 1.0% by weight or less and the total amount of the stabilizer and anions of the silver salt is 2.0% by weight or less; an antibacterial resin composition comprising 100 parts by weight of an acrylic, urethane, epoxy or ester resin, 0.

Abstract: Disclosed is a paint composition having high far-infrared emissivity, antibiotic activity and solvent resistance and a precoated metal sheet for home appliances, coated with the paint composition. The paint composition includes a thermosetting resin, 9-60 parts by weight of ceramic powder and 0.2-4.0 parts by weight of phosphoric acid, based on 100 parts by weight of the thermosetting resin, is provided, and a precoated metal sheet coated with such a paint composition is also provided. The paint composition and the precoated metal sheet coated with the paint composition manifest high far-infrared emissivity and antibiotic activity, and as well, have storage stability and solvent resistance increased by neutralizing the alkalinity of ceramic powder using phosphoric acid. Further, a silane compound and a curing catalyst are additionally used to increase gloss and processability.

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.

Abstract: A spangle-free, hot-dip galvanized steel sheet, and a method and device for manufacturing the same. The hot-dip galvanized steel sheet is characterized in that a solidified zinc crystal of hot-dip galvanized layer has an average crystalline texture particle diameter of 10 to 88 ?m and there is no solidification traces of dendrites upon observing under a microscope at a magnification of 100×. The method comprises dipping a steel sheet in a bath of a zinc-coating solution containing 0.13 to 0.3% by weight of aluminum; air-wiping the steel sheet to remove an excess of the coating solution; spraying water or an aqueous solution on the air-wiped steel sheet, using a steel sheet temperature in the range of a hot-dip galvanization temperature to 419° C. as a spray initiation temperature and using a steel sheet temperature in the range of 417° C. to 415° C.

Abstract: Disclosed herein is a weldable pre-sealed steel sheet with improved corrosion resistance and weldability. The pre-sealed steel sheet comprises (a) a metal base, (b) a chromium-free pre-treatment coating layer formed on at least one surface of the metal base, and (c) a pre-sealed resin coating layer formed on at least one surface Chromium-free pretreatment of the chromium-free pretreatment coating layer. Since the weldable pre-sealed steel sheet does not contains heavy metals (e.g., chromium) harmful to humans, it is environmentally friendly. In addition, the weldable pre-sealed steel sheet exhibits superior corrosion resistance, chemical resistance, processability, electrodeposition paintability and adhesiveness after processing, as well as improved weldability.

Abstract: Disclosed is a paint composition having high far-infrared emissivity, antibiotic activity and solvent resistance and a precoated metal sheet for home appliances, coated with the paint composition. The paint composition includes a thermosetting resin, 9-60 parts by weight of ceramic powder and 0.2-4.0 parts by weight of phosphoric acid, based on 100 parts by weight of the thermosetting resin, is provided, and a precoated metal sheet coated with such a paint composition is also provided. The paint composition and the precoated metal sheet coated with the paint composition manifest high far-infrared emissivity and antibiotic activity, and as well, have storage stability and solvent resistance increased by neutralizing the alkalinity of ceramic powder using phosphoric acid. Further, a silane compound and a curing catalyst are additionally used to increase gloss and processability.