Thermochromic pigment compositions

Patent metadata

Field	Value
Publication number	US-11655387-B2
Application number	US-201816608466-A
Country	US
Kind code	B2
Filing date	Apr 24, 2018
Priority date	Apr 27, 2017
Publication date	May 23, 2023
Grant date	May 23, 2023

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.

First claim

The invention claimed is:

1. A thermochromic pigment composition comprising:
(A) at least one electron-donor dye compound,
(B) at least one electron-acceptor compound, and
(C) at least one compound serving as a reaction medium capable of bringing about a reversible electron-acceptance/donation reaction attributable to compounds (A) and (B), the at least one compound corresponding to the following formula (I):

in which:
X represents O or a single bond,
Z represents COO or OCO,
R 1 represents O-alkyl or (CH 2 ) m CH 3 ,
R 2 represents OCO(CH 2 ) n CH 3 or H,
y=0-3,
m=12-18,
n=12-18,
p=8-18, and

in the condition that when X is O, y does not equal 0, wherein the at least one electron-donor dye compound is present at from 1% to 10% by weight, wherein the at least one electron-acceptor compound is present at from 1% to 10% by weight, and wherein the at least one compound corresponding to the following formula (I) is present at from 70% to 98% by weight based on the total weight of the composition.

2. The thermochromic composition according to claim 1 , wherein the at least one compound of the formula (I) corresponds to the following formula (I a ):

in which:
X represents O or a single bond,
Z represents COO or OCO,
R 1 represents O—C 1-6 alkyl or (CH 2 ) m CH 3 ,
y=0-3,
m=12-18, and
p=8-18.

3. The thermochromic composition according to claim 2 , wherein the at least one compound of the formula (I a ) is a compound in which:
X represents a single bond,
Z represents OCO,
R 1 represents (CH 2 ) m CH 3 ,
y=0,
m=12-18, and
p=8-18.

4. The thermochromic composition according to claim 1 , wherein the compound (A) is selected from the group consisting of 3-(4-diethylamino-2-ethoxyphenyl)-3-(1-ethyl-2-methylindol-3-yl)-4-azaphthalide (Blue 63), 2′-(dibenzylamino)-6′-(diethylamino)fluorane, N,N-dimethyl-4-[2-[2-(octyloxy)phenyl]-6-phenyl-4-pyridinyl]benzenamine (Yellow CK37), 7-(4-diethylamino-2-hexyloxyphenyl)-7-(1-ethyl-2-methyl-1H-indol-3-yl)-7H-furo[3,4-b]pyridine-5-one (Blue 203), 2-(2,4-dimetylphenylamino)-3-methyl-6-diethylaminofluoran (Black 15), and 3,3-bis-(1-butyl-2-methyl-indol-3-yl)-3H-isobenzofuran-1-one (Red 40).

5. The thermochromic composition according to claim 1 , wherein the compound (B) is selected from the group consisting of 2,2-bis(4-hydroxy-3-methylphenyl)propane (Bisphenol C), 4-hexyl-1,3-dihydrxybenzene (4-hexylresorcinol), 4,4′-cyclohexylidene bisphenol (BPZ), 4,4′-(1-phenylethylidene)bisphenol, 2,2′-dihydroxybiphenyl, 4,4′-(1,4-phenylenediisopropylidene)bisphenol, 1,1-bis(4-hydroxy-3-methylphenyl)cyclohexane, 9,9-bis(4-hydroxyphenyl)fluorene, 4,4′-(1,3-phenylenediisopropylidene)bisphenol, 1,1,1-tris(4-hydroxyphenyl)ethan, 4,4′-(2-ethylhexylidene)diphenol, and α,α,α′-tris(4-hydroxyphenyl)-1-ethyl-4-isopropylbenzene.

6. A thermochromic pigment microcapsule containing the thermochromic pigment composition according to claim 1 .

7. An ink composition containing a plurality of the thermochromic pigment microcapsule according to claim 6 .

8. A writing instrument containing the ink composition according to claim 7 .

9. The writing instrument according to claim 8 , wherein the writing instrument is a friction erasable ballpoint ink pen.

Assignees

• SOCIéTé BIC

Inventors

• Debrauwer Christelle
• Damiano Anne-Lise
• Bourque Alexander
• Foulonneau Francois
• Chollet Guillaume

Classifications

• C09D11/50 Primary

  Sympathetic, colour changing or similar inks · CPC title

• C09B67/0097

  Dye preparations of special physical nature; Tablets, films, extrusion, microcapsules, sheets, pads, bags with dyes · CPC title

• C09D11/18 Primary

  specially adapted for ball-point writing instruments · CPC title

• C09K9/02

  Organic tenebrescent materials · CPC title

• C09D11/17

  characterised by colouring agents · CPC title