To provide a pressure sensitive recording material for performing color developing color tone near a pure black with scarce effect of adverse influence of light and nitrogen oxide by using mixed dye containing green developing fluoran compound and red developing fluoran compound as main component.
As leuco dye, fluoran compound represented by a formula I and fluoran compound represented by a formula II are combined to occupy 50wt.% or more of the total leuco dye, where R1, R2, R3, R4 indicate 2-5C alkyl group. The fluoran compound of the formula I is green developable leuco dye, and the fluoran compound of the formula II is red developable leuco dye. Since the compound of the formula I has a slight difficulty of manufacturing yield, black developable fluoran represented by a formula III can be combined with the compounds of the formulae I and II to occupy 90wt.% or more of the leuco dye, where R5, R6 indicate 2-5C alkyl group.
UMEHARA JUNKO
IWAMOTO YOSHIORI
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