Abstract: A laminate includes a void-containing layer, and a pressure-sensitive adhesive/adhesive layer directly laminated on one surface or both surfaces of the void-containing layer. The pressure-sensitive adhesive/adhesive layer includes a pressure-sensitive adhesive/adhesive including a (meth)acrylic polymer and an organic silyl group-containing compound. 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): (|n?n0|/n0)×100<3.0 (1). In the formula (1), n represents the refractive index of the void-containing layer after the heat durability test, and n0 represents the refractive index of the void-containing layer before the heat durability test.

Abstract: A bonding method for providing an adhesive layer and a curing agent layer between a first adherend and a second adherend to bond the first adherend and the second adherend in which: the adhesive layer contains an epoxy resin as a main component and is cured by an effect of the curing agent layer; a curing agent contained in the curing agent layer is a polymerization catalyst type curing agent; and a thickness A (m) of the adhesive layer before curing and the application amount B (kg/m2) of the curing agent contained in the curing agent layer satisfy 5<B/A<900.

Abstract: A sensor package attached to an object contains a first base material; and an optical fiber having an FBG sensor portion disposed on the first base material. The sensor package includes a resin portion located on the first base material, a first adhesive layer located on the first base material to attach the first base material to the object, and a bonding adhesive layer located on a surface of the resin portion on a side opposite to the first base material, and the FBG sensor portion of the optical fiber is in contact with the resin portion and held by the bonding adhesive layer.

Abstract: A laminate includes: a void-containing layer and a pressure-sensitive adhesive/adhesive layer. 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 contains a (meth)acrylic polymer, and nanoindentation hardness of the pressure-sensitive adhesive/adhesive layer is 0.1 MPa or more and 1.0 MPa or less.

Abstract: A bonding method for providing an adhesive layer and a curing agent layer between a first adherend and a second adherend to bond the first adherend and the second adherend in which: the adhesive layer contains an epoxy resin as a main component and is cured by an effect of the curing agent layer; a curing agent contained in the curing agent layer is a polymerization catalyst type curing agent; and a thickness A (m) of the adhesive layer before curing and the application amount B (kg/m2) of the curing agent contained in the curing agent layer satisfy 5<B/A<900.

Abstract: An optical-fiber-embedding sheet which is a strip-shaped sheet material containing an optical fiber to be used as a sensor and is configured of a base material and an adhesive layer formed thereover which is to be bonded to a placement object where the optical fiber is to be placed, the optical fiber having been embedded in the adhesive layer. The optical fiber is placed by applying a primer, which is for curing the adhesive layer by a chemical reaction with the adhesive layer, to a placement object for the optical fiber and thereafter applying the optical-fiber-embedding sheet to the portion of the placement object to which the primer has been applied.