Aqueous polyurethane resin dispersion, process for preparing the same and use thereof

An aqueous polyurethane resin dispersion comprising a polyurethane resin obtained by reacting (a) a polyol compound, (b) a polyisocyanate compound, (c) an acidic group-containing polyol compound and (d) a chain-elongating agent being dispersed in an aqueous medium, wherein

• (a) the polyol compound comprises a polycarbonate polyol compound represented by the formula (1):
• wherein
• R1 and R2 each independently represent a direct bond or an aliphatic hydrocarbon group having 1 to 10 carbon atoms which may have a substituent(s),
• n is 0 or 1,
• m is a number which makes a number average molecular weight of the formula (1) 400 to 2000,
• a hydroxyl equivalent of (a) the polyol compound and (c) the acidic group-containing polyol compound is 180 to 400, and
• a total acid value of (a) the polyol compound, (b) the polyisocyanate compound and (c) the acidic group-containing polyol compound is 22 to 40 mg KOH/g.