Laminate, optical member, and optical device

A laminate, comprising:

• a void-containing layer, and
• a pressure-sensitive adhesive/adhesive layer, wherein
• the pressure-sensitive adhesive/adhesive layer is directly laminated on one surface or both surfaces of the void-containing layer,
• the pressure-sensitive adhesive/adhesive layer comprises:
• a pressure-sensitive adhesive/adhesive including:
• a (meth)acrylic polymer, and
• an organic silyl group-containing compound, and
• an increase rate of a refractive index of the void-containing layer before and after a heat durability test of holding the laminate at a temperature of 65° C. and a relative humidity of 95% for 500 hours satisfies the following formula (1):
• (
• ❘
• "\[LeftBracketingBar]"
• n
• -
• n
• 0
• ❘
• "\[RightBracketingBar]"
• /
• n
• 0
• )
• ×
• 100
• <
• 3.
• (
• 1
• )
• where, in the formula (1),
• n represents the refractive index of the void-containing layer after the heat durability test, and no represents the refractive index of the void-containing layer before the heat durability test.