Abstract: A thermochromic pigment composition including: (A) at least one electron-donor organic dye compound, (B) at least one electron-acceptor compound, and (C) at least one compound corresponding to the following formula (I): in which: X is 0 or a single bond, Z is COO or OCO, R1 is O-alkyl or (CH2)mCH3—R2 is OCO(CH2)nCH3 or H, —y=0-3, —m=12-18; —p=8-18, and on the condition that, when X is 0, y is other than 0. The thermochromic pigment composition are also useable in thermochromic pigment microcapsules ink compositions including the thermochromic pigment microcapsules, and writing instruments including the ink compositions.

Abstract: A thermochromic pigment composition including: (A) at least one electron-donor organic dye compound, (B) at least one electron-acceptor compound, and (C) at least one compound corresponding to the following formula (I): in which: X is 0 or a single bond, Z is COO or OCO, R1 is O-alkyl or (CH2)mCH3—R2 is OCO(CH2)nCH3 or H, —y=0-3, —m=12-18; —p=8-18, and on the condition that, when X is 0, y is other than 0. The thermochromic pigment composition are also useable in thermochromic pigment microcapsules ink compositions including the thermochromic pigment microcapsules, and writing instruments including the ink compositions.

Abstract: A thermochromic pigment composition including: (A) at least one electron-donor organic dye compound, (B) at least one electron-acceptor compound, and (C) at least one compound responding to the following formula (I), in which: R1 is H or a phenyl group, —R2 is H or a phenyl group, and -n=1-8. The thermochromic pigment composition includes thermochromic pigment microcapsules ink compositions including such thermochromic pigment microcapsules, and writing instruments including such ink compositions.

Abstract: A thermochromic pigment composition including compounds of formula (I): in which: X represents CHR2, O, OCO or CH?CH; Y represents O, COO, or OCOO; R1 represents H or (CH2)pCH3; R2 represents phenyl or H; m=12-18; n=0-14; p=12-18; and on the condition that, if n=0, X represents CHR2 or CH?CH. The thermochromic pigment compositions having compounds of formula (I), include thermochromic pigment microcapsules. The thermochromic pigment capsules are useable for thermochromic pigment compositions in ink which may be used writing instruments.