Antireflection substrate

1 . An antireflection substrate which has a predetermined elongation percentage of 120% to 160%, comprising:

a resin substrate; and

an underlying layer, a hard coat layer, an antireflection layer, and a cover layer which are provided on the resin substrate in this order,

wherein the underlying layer is formed of a cured material of a hexafunctional or higher functional urethane (meth)acrylate compound (A1),

the hard coat layer contains a cured material of a urethane (meth)acrylate compound (A) containing 60% by mass or more of a trifunctional or less functional urethane (meth)acrylate compound (A2),

the antireflection layer includes an intermediate refractive index layer having a refractive index of 1.50 to 1.75, a high refractive index layer having a refractive index of 1.60 to 2.00, and a low refractive index layer having a refractive index of 1.25 to 1.40 in this order from the hard coat layer side, the refractive index of the high refractive index layer being higher than that of the intermediate refractive index layer, and the intermediate refractive index layer, the high refractive index layer, and the low refractive index layer all contain a cured material of an organic/inorganic composite compound (B),

the cover layer includes a cured material of the organic/inorganic composite compound (B), and

the organic/inorganic composite compound (B) is a composite compound having a structure in which an alkoxysilyl group is bonded to any of a bisphenol A-type epoxy resin, a novolac phenol resin, and a polyamic acid.

2 . The antireflection substrate according to claim 1 , wherein the hard coat layer is formed of a cured material of a composition containing 30 to 80 parts by mass of spherical silica particles (C-1), 5 to 15 parts by mass of a silane coupling agent (D), and 0.1 to 1.5 parts by mass of a metal chelate compound (E) with respect to 100 parts by mass of the urethane (meth)acrylate compound (A) containing 60% by mass or more of a trifunctional or less functional urethane (meth)acrylate compound (A2),

the intermediate refractive index layer is formed of a cured material of a composition containing 50 to 170 parts by mass of metal oxide particles (F), 50 to 100 parts by mass of a silane coupling agent (D), and 1 to 10 parts by mass of a metal chelate compound (E) with respect to 100 parts by mass of the organic/inorganic composite compound (B),

the high refractive index layer is formed of a cured material of a composition containing 500 to 1500 parts by mass of metal oxide particles (F), 100 to 300 parts by mass of a silane coupling agent (D), and 10 to 30 parts by mass of a metal chelate compound (E) with respect to 100 parts by mass of the organic/inorganic composite compound (B),

the low refractive index layer is formed of a cured material of a composition containing 100 to 300 parts by mass of hollow silica particles (C-2), 20 to 150 parts by mass of a silane coupling agent (D), and 1 to 10 parts by mass of a metal chelate compound (E) with respect to 100 parts by mass of the organic/inorganic composite compound (B), and

the cover layer is formed of a cured material of a composition containing 10 to 80 parts by mass of a silane coupling agent (D) and 1 to 10 parts by mass of a metal chelate compound (E) with respect to 100 parts by mass of the organic/inorganic composite compound (B).

3 . The antireflection substrate according to claim 1 , wherein the underlying layer has a thickness of 20 nm to 150 nm, the hard coat layer has a thickness of 1 μm to 5 μm, the intermediate refractive index layer has a thickness of 50 nm to 200 nm, the high refractive index layer has a thickness of 50 nm to 200 nm, the low refractive index layer has a thickness of 50 nm to 200 nm, and the cover layer has a thickness of 10 nm to 20 nm.

4 . An antireflection film for film insert molding comprising the antireflection substrate according to claim 1 .