Abstract: A chromene compound having a short fading half period, especially, a short fading half period even at a low temperature in a general-purpose polymer solid matrix. The chromene compound is represented by the following formula (1). wherein R1 is a hydroxyl group or the like, R2 and R3 are each an aryl group or the like, C* is a spiro carbon atom, a spiro ring A represented by the following formula is a saturated hydrocarbon ring having 4 to 12 ring member carbon atoms or the like, and at least one ring member carbon atom constituting the ring A is a group represented by the following formula (4), and X is a divalent group such as arylene group, wherein R7 and R8 are each a cycloalkyl group or the like.

Abstract: A chromene compound having a short fading half period, especially, a short fading half period even at a low temperature in a general-purpose polymer solid matrix. The chromene compound is represented by the following formula (1). wherein R1 is a hydroxyl group or the like, R2 and R3 are each an aryl group or the like, C* is a spiro carbon atom, a spiro ring A represented by the following formula is a saturated hydrocarbon ring having 4 to 12 ring member carbon atoms or the like, and at least one ring member carbon atom constituting the ring A is a group represented by the following formula (4), and X is a divalent group such as arylene group, wherein R7 and R8 are each a cycloalkyl group or the like.

Abstract: Disclosed is an anion-exchange membrane which does not easily deteriorate even when used at high temperatures in a strong alkaline atmosphere. Also disclosed is a method for producing the anion-exchange membrane. The anion-exchange membrane is a microporous membrane which is composed of a water-insoluble resin and an anion-exchange resin filling the pores of the microporous membrane. The anion-exchange resin is composed of an anion-exchange resin wherein a quaternary ammonium salt group serving as an anion-exchange group is directly bonded to an aliphatic hydrocarbon chain, said anion-exchange resin being obtained by polymerizing and crosslinking a monomer composition which contains a crosslinking agent and a monomer component including a diallyl ammonium salt.