Deep Color Effect

The effect of shifting the absorption of a substance to longer wavelengths and deepening the color. Generally, when substituted with a functional group, the absorption band of an organic dye is shifted to longer wavelengths and the color deepens. Such substituents are called bathochromic groups. Auxochromic groups such as amino and hydroxyl groups generally provide a bathochromic effect, but this effect differs depending on the position of substitution. The shift of the absorption band to longer wavelengths is called a red shift. [See alternative term] Hypochromic effect

Source: Morikita Publishing "Chemical Dictionary (2nd Edition)" Information about the Chemical Dictionary 2nd Edition

物質の吸収が長波長にずれ，色が深くなる効果．有機色素の吸収帯は，一般に官能基で置換すると長波長にずれ，その色は深くなる．このような置換基は深色団といわれる．アミノ基やヒドロキシ基などの助色団は，一般に深色効果を与えるが，この効果は置換する位置によっても異なる．なお，吸収帯が長波長にずれることをレッドシフトという．[別用語参照]浅色効果

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