| 摘要 |
PROBLEM TO BE SOLVED: To provide an aqueous acrylic urethane resin composition wherein a cured product obtained therefrom by being cured not only has excellent scratch resistance with high surface hardness but also has remarkable crack resistance and sweat resistance, and further the cured product is suitable as a surface protection material for a cellular phone or home electric appliances.SOLUTION: This aqueous acrylic urethane resin composition includes 2-70 mass% total solid portion containing a polyurethane resin (A) and a polyfunctional (meth)acrylate compound (B) having 4-6 acrylic groups so that the ratio of each solid portion falls 10:90 to 50:50 in terms of the mass ratio. The aqueous acrylic urethane resin composition is produced as follows. A urethane prepolymer (A') component obtained by reacting together a diol component (a) having a number-average molecular weight of 500-3,000, a polyisocyanate component (b), an anionic group-introduced compound (c) having a carboxy group, and an active hydrogen group-containing compound (d) having 3-4 active hydrogen groups which are a hydroxy group or an amino group respectively in one molecule and having a molecular weight of <500 is mixed with the compound (B), and the mixture is dispersed in water, and then a chain extender (e) is added thereto and mixed therewith, to thereby subject the urethane prepolymer (A') to chain extension. In this case, the acid value of the (A') component based on the carboxy group in the (c) component is 25-50 mgKOH/g, and the blending amount of the active hydrogen group-containing compound (d) is 0.05-0.2 in terms of the mole ratio of the active hydrogen group in (d) to 1 mole of an isocyanate group in the polyisocyanate component (b). |
