This polyurethane urea resin (U) has as essential constituent monomers thereof polyol (A), polyisocyanate (B), and a chain extender (C) having a number average molecular weight or chemical formula weight of less than 500. The polyol (A) includes a polyfarnesene polyol (A1) and/or a hydrogenated product (A2) of the polyfarnesene polyol (A1). The chain extender (C) contains at least one type of compound selected from the group consisting of: a diamine (C11) that has a cyclic skeleton other than an aromatic ring; a diamine (C12) that does not have a ring skeleton and does have a chain hydrocarbon group including a heteroatom other than a nitrogen atom in the chain; a diamine (C13) other than the diamines (C11) and (C12), that has a hydroxy group; a triamine (C14) that has a cyclic skeleton other than an aromatic ring; and a triamine (C15) that has a chain hydrocarbon group and does not have a cyclic skeleton; and water. The urea group concentration in the polyurethane urea resin (U) is 0.05–1.5 mmol/g.
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