Elastomer reinforcement cord

An elastomer reinforcement cord, comprising metal filaments and a polymer material,

• wherein
• the elastomer reinforcement cord has a multi-strand structure including:
• at least one core strand formed by twisting plural metal filaments together;
• and two or more sheath strands each formed by twisting plural metal filaments together, the sheath strands being twisted together around the core strand,
• when, at a cross-section taken in a direction orthogonal to an axial direction after vulcanization, a region that is surrounded by a line connecting the centers of outermost-layer metal filaments of the respective sheath strands and occupied by other than the metal filaments is defined as an intra-sheath-strand gap region A, an intra-sheath-strand filling rate a, which is a ratio of the area of the polymer material with respect to the intra-sheath-strand gap region A, is 52% or higher, and
• when, at a cross-section taken in a direction orthogonal to the axial direction after vulcanization, a region between outermost-layer metal filaments of the core strand and the outermost-layer metal filaments of the sheath strands facing the outermost-layer metal filaments of the core strand is defined as an inter-strand gap region B, an inter-strand filling rate b, which is a ratio of the area of the polymer material with respect to the inter-strand gap region B, is 75% or higher, and
• wherein a distance between the outermost-layer metal filaments of the sheath strands is 20 μm or less.