阅读说明：本技术 新颖式（i）化合物和其在热致变色颜料组合物中的用途 (Novel compounds of formula (I) and their use in thermochromic pigment compositions ) 是由 C·德布拉威尔 A-L·达米奥诺 A·布尔克 F·弗洛诺 G·肖莱 于 2018-04-24 设计创作，主要内容包括：本发明涉及新颖式(I)化合物：<Image he="251" wi="700" file="DDA0002245670210000011.GIF" imgContent="drawing" imgFormat="GIF" orientation="portrait" inline="no"></Image>其中：X表示CHR<Sub>2</Sub>、O、OCO或CH＝CH；Y表示O、COO或OCOO；R<Sub>1</Sub>表示H或(CH<Sub>2</Sub>)<Sub>p</Sub>CH<Sub>3</Sub>；R<Sub>2</Sub>表示苯基或H；m＝12-18；n＝0-14；p＝12-18；并且条件是,如果n＝0,则X表示CHR<Sub>2</Sub>或CH＝CH。本发明还提供了包括根据本发明的式(I)化合物的热致变色颜料组合物、包括这种热致变色颜料组合物的热致变色颜料微胶囊、包括这种热致变色颜料微胶囊的油墨组合物以及最后包括这种油墨组合物的书写工具。(The present invention relates to novel compounds of formula (I): wherein: x represents CHR 2 O, OCO or CH ═ CH; y represents O, COO or OCOO; r 1 Represents H or (CH) 2 ) p CH 3 ；R 2 Represents phenyl or H; m is 12-18; n is 0 to 14; p is 12-18; and with the proviso that if n is 0, then X represents CHR 2 Or CH ═ CH. The present invention also provides thermochromic pigment compositions comprising a compound of formula (I) according to the invention, thermochromic pigment microcapsules comprising such thermochromic pigment compositions, ink compositions comprising such thermochromic pigment microcapsules and finally writing instruments comprising such ink compositions.)

1. A compound corresponding to the following formula (I):

wherein:

-X represents CHR₂O, OCO or CH-CH,

-Y represents O or COO,

-R₁represents H or (CH)₂)_pCH₃，

-R₂Represents a phenyl group or a hydrogen group,

-m＝12-18，

-n＝0-14，

-p is 12-18, and

provided that if n is 0, X represents CHR₂Or CH ═ CH.

2. The compound of claim 1, wherein:

-X represents CHR₂O, or an OCO, or a mixture thereof,

-Y represents O or COO,

-R₁represents H or (CH)₂)_pCH₃，

-R₂Represents a phenyl group or a hydrogen group,

-m＝12-18，

-n＝0-14，

-p is 12-18, and

provided that if n is 0, X represents CHR₂。

3. The compound of claim 1, corresponding to formula (I) below_a)：

Wherein:

-m is 12 to 18, and

-n＝1-14。

4. a compound according to claim 1 or claim 2, corresponding to formula (I) below_b)：

Wherein:

-m is 12 to 18, and

-n＝0-14。

5. a compound according to claim 1 or claim 2, corresponding to formula (I) below_c)：

Wherein:

-X represents CH₂O or CH ═ CH,

-Y represents O or COO,

-m is 12 to 18, and

-n＝1-14。

6. the composition according to any one of claims 1 to 5, selected from the following compounds:

7. a thermochromic pigment composition comprising:

(A) at least one organic electron-donating dye compound,

(B) at least one electron-accepting compound, and

(C) at least one compound of formula (I) according to any one of claims 1 to 6.

8. The composition according to claim 7, 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 color 63, CAS number 69898-40-4), 2'- (dibenzylamino) -6' - (diethylamino) fluoran (CAS number 34372-72-0), N-dimethyl-4- [2- [2- (octyloxy) phenyl ] -6-phenyl-4-pyridyl ] aniline (yellow CK37, CAS number 144190-25-0), 7- (4-diethylamino-2-hexyloxyphenyl) -7- (1-ethyl-2-methyl- 1H-indol-3-yl) -7H-furo [3,4-b ] pyridin-5-one (blue 203, CAS No.: 98660-18-5), 2- (2, 4-dimethylphenylamino) -3-methyl-6-diethylaminofluoran (black 15, CAS No.: 36431-22-8) and 3, 3-bis- (1-butyl-2-methyl-indol-3-yl) -3H-isobenzofuran-1-one (red 40, CAS No.: 50292-91-6).

9. The composition according to claim 7 or claim 8, wherein compound (B) is selected from the group consisting of 2, 2-bis (4-hydroxy-3-methylphenyl) propane (bisphenol C, CAS number: 79-97-0), 4-hexyl-1, 3-dihydroxybenzene (4-hexylresorcinol, CAS number: 136-77-6), 4' -cyclohexylidenebisphenol (BPZ, CAS number: 843-55-0), 4' - (hexafluoroisopropylidene) diphenol (bisphenol AF, CAS number: 1478-61-1), 4' - (1-phenylethylidene) diphenol (CAS number: 1571-75-1), 2' -dihydroxybiphenyl (CAS number: 1806-29-7), 4' - (1, 4-phenylene diisopropylidene) bisphenol (CAS No.: 2167-51-3), 1-bis (4-hydroxy-3-methylphenyl) cyclohexane (CAS No.: 2362-14-3), 9-bis (4-hydroxyphenyl) fluorene (CAS No.: 3236-71-3), 4' - (1, 3-phenylenediisopropylidene) bisphenol (CAS No.: 13595-25-0), 1,1, 1-tris (4-hydroxyphenyl) ethane (CAS No.: 27955-94-8), 4' - (2-ethylhexyl) diphenol (CAS No.: 74462-02-5) and α, α, α' -tris (4-hydroxyphenyl) -1-ethyl-4-isopropylbenzene (CAS No.: 110726-28-8).

10. A thermochromic pigment microcapsule comprising the composition according to any one of claims 7 to 9.

11. An ink composition comprising the thermochromic pigment microcapsules according to claim 10.

12. A writing instrument comprising the ink composition according to claim 11.

13. The writing instrument of claim 12 selected from the group consisting of ball point pens with a friction erasable ink.

Background

Thermochromic pigment compositions have reversible discoloration properties associated with changes in temperature. These compositions are used when the ink marks need to be erased repeatedly.

The thermochromic effect of the ink is achieved by a combination of three compounds:

(A) at least one organic electron donor dye or leuco dye compound,

(B) at least one electron acceptor or developer compound, and

(C) at least one compound acting as a reaction medium, said compound being capable of generating a reversible electron-accepting/donating reaction attributable to the compounds (a) and (B) or to the thermochromic regulator.

The temperature change reversibly causes the ink to be colored or decolored. Thus, an increase in heat will cause ink erasure, while cooling will cause ink to appear. These variations follow the schematic diagram in fig. 1. In this schematic diagram, the temperature at which the ink starts to disappear is T3, the temperature at which the ink color completely disappears is T4, and TG is an intermediate temperature between T3 and T4. In contrast, the temperature at which the ink color starts to be reproduced is T2, the temperature at which the ink color is completely reproduced is T1, and TH is an intermediate temperature between T1 and T2. The range between (TH) and (TG) is referred to as a color change hysteresis width (Δ H).

Surprisingly, the inventors have found novel compounds capable of preparing thermochromic pigment microcapsules having optimal melting and crystallization temperature ranges corresponding to the decolorization and recolorization temperatures of the compositions, respectively. Thus, the compounds of the present invention provide a number of advantages for use as thermochromic regulators in thermochromic inks: the compounds exhibit significant hysteresis characteristics and extremely high color contrast between the colored and bleached states. The novel compounds of the present invention also have the advantage of being preparable by an ecological process, i.e. from 3-pentadecylphenol, a product derived from the recycling of cashew production waste and of biological origin.

Disclosure of Invention

According to a first aspect, the object of the present invention is a compound corresponding to formula (I) below:

wherein:

-X represents CHR₂O, OCO or CH-CH,

-Y represents O or COO,

-R₁represents H or (CH)₂)_pCH₃，

-R₂Represents a phenyl group or a hydrogen group,

-m＝12-18，

-n＝0-14，

-p is 12-18, and

provided that if n is 0, X represents CHR₂Or CH ═ CH.

In an aspect of the invention:

-if X ═ OCO: the oxygen atom is linked to the phenyl group and the carbonyl group is linked to (CH)₂)_nA chain, and

-if Y ═ COO: the carbonyl group is attached to (CH)₂)_nAnd the oxygen atoms are attached to phenyl groups.

In formula (I) above, X is preferably selected from CHR₂O or OCO.

In formula (I) above, m may be independently selected from the following integers: 12. 13, 14, 15, 16, 17 or 18.

In formula (I) above, n may be independently selected from the following integers: 0. 1,2, 3,4, 5, 6, 7, 8, 9, 10, 11, 12, 13, or 14.

In formula (I) above, p may be independently selected from the following integers: 12. 13, 14, 15, 16, 17 or 18.

In the above formula (I), preferably, n is 0 to 10.

In formula (I) above, preferably, p ═ 14.

Advantageously, the compound of formula (I) according to the invention is a compound wherein:

-X represents CHR₂O, or an OCO, or a mixture thereof,

-Y represents O or COO,

-R₁represents H or (CH)₂)_pCH₃，

-R₂Represents a phenyl group or a hydrogen group,

-m is 12 to 18, and

-n-0-14, preferably n-0-10;

-p-12-18, preferably p-14;

provided that if n is 0, X represents CHR₂。

According to a first preferred embodiment, the compounds of the invention correspond to the following formula (I)_a)：

Wherein:

-m is 12 to 18, and

-n-1-14, preferably n-1-10;

advantageously, in the formula (I) of the present invention_a) The method comprises the following steps: m is 14, and m is 14,

advantageously, in the formula (I) of the present invention_a) The method comprises the following steps: n is 8.

According to a second preferred embodiment, the compounds of the invention correspond to formula (I) below_b)：

Wherein:

-m is 12 to 18, and

-n-0-14, preferably n-0-10.

Advantageously, in the formula (I) of the present invention_b) The method comprises the following steps: m is 14, and m is 14,

advantageously, in the formula (I) of the present invention_b) The method comprises the following steps: n is 1.

According to a third preferred embodiment, the compounds of the invention correspond to formula (I) below_c)：

Wherein:

-X represents CH₂O or CH ═ CH,

-Y represents O or COO,

-m is 12 to 18, and

-n-1-14, preferably n-1-10, and even more preferably n-1-8.

Advantageously, in the formula (I) of the present invention_C) The method comprises the following steps: m is 14, and m is 14,

advantageously, in the formula (I) of the present invention_C) The method comprises the following steps: n is 2.

Formula (I)_a)、(I_b) And (I)_c) The compounds can be synthesized according to the first two synthetic routes described below. Formula (I)_c) The compound can be synthesized according to the third synthesis route described below.

The first synthetic pathway corresponds to the following reaction scheme:

in this first synthetic route, the alcohol acts as a solvent. The alcohol is used in excess, preferably with an alcohol to carboxylic acid ratio of 1.5:1 to 3:1, and even more preferably 2: 1. The mixture of alcohol and carboxylic acid is heated under reduced pressure (preferably between 200 mbar and 800 mbar) to a temperature in the range of 120 ℃ to 200 ℃, preferably 140 ℃ to 160 ℃, until the acid is completely consumed. The mixture was heated under reduced pressure for a period of 1 to 4 days. The obtained formula (I) is then purified by recrystallization_a)、(I_b) Or (I)_c) A compound is provided.

The second synthetic pathway corresponds to the following reaction scheme:

in the second synthetic route, phenol is dissolved together with a catalyst in an aprotic polar solvent such as Tetrahydrofuran (THF). The catalyst is preferably a volatile base such as triethylamine. The mixture is kept cooled at a temperature in the range of-20 ℃ to 30 ℃, preferably 0 ℃ to 20 ℃. Immersing the mixture in ice bath or solid CO in solvent such as acetone or ethanol₂The bath was kept cool. Advantageously, the mixture is rendered inert by the addition of nitrogen. The acid chloride was then added slowly dropwise over a period of 15 to 60 minutes. The alcohol to acid chloride ratio used is preferably from 1.1:1 to 1:1.1, and even more preferably 1:1. The temperature of the mixture is then raised to room temperature (25 ℃) and the mixture is kept at this temperature while stirring for 1 to 3 hours, preferably for 2 hours. The obtained formula (I) is then purified by recrystallization_a)、(I_b) Or (I)_c) A compound is provided.

Formula (I)_c) The compounds can also be synthesized according to the following synthetic routes:

wherein the substituent X' represents a halogen atom selected from Cl, Br, I or F, preferably a Br atom.

In this synthetic route, the formula (I) can be prepared_c) A compound:

by dissolving the reagent in a polar solvent such as tert-butanol in the presence of a strong base such as sodium hydroxide. The alcohol to halogenated compound ratio used is preferably from 1:1 to 1.4:1 and even more preferably 1.2: 1. The reagent mixture is heated at 75 to 90 ℃ for 2 to 10 hours, preferably 6 hours, under reflux. The obtained formula (I) is then purified by recrystallization_c) A compound is provided.

Or by dissolving the reagent in a polar solvent such as acetonitrile in the presence of a strong base such as potassium carbonate. The alcohol to halogenated compound ratio used is preferably from 1:1 to 1.4:1 and even more preferably 1.2: 1. The reagent mixture is heated at 75 to 90 ℃ for 5 to 10 days, preferably 7 days, under reflux. The mixture is then filtered to remove the weak base. The obtained formula (I) is then purified by recrystallization_c) A compound is provided.

The compounds of formula (I) of the present invention are preferably selected from the following compounds:

the melting temperature of the compounds of formula (I) of the present invention may vary from 20 ℃ to 80 ℃, preferably from 30 ℃ to 80 ℃, and even more preferably from 40 ℃ to 70 ℃. It is this optimum melting temperature that makes the compounds of formula (I) of the present invention ideal compounds with the desired properties for use as thermochromic modulators in thermochromic pigment compositions.

Therefore, another object of the present invention is a thermochromic pigment composition comprising:

(A) at least one organic electron donor dye or leuco dye compound,

(B) at least one electron acceptor or developer compound, and

(C) at least one compound of formula (I) as defined according to the invention.

The weight ratio of the compounds (A), (B) and (C) is influenced by the nature and concentration of each of these compounds.

The weight ratio of the organic electron donating dye compound (a) can be 1 to 10 weight%, preferably 1 to 6 weight%, and even more preferably 2 to 4 weight%, relative to the total weight of the thermochromic pigment composition.

The weight ratio of the electron accepting compound (B) may be from 1 to 20 wt%, preferably from 1 to 14 wt%, and even more preferably from 4 to 10 wt%, relative to the total weight of the thermochromic pigment composition.

The weight ratio of the compound (C) of formula (I) acting as reaction medium may be from 70 to 98% by weight, preferably from 80 to 98% by weight, and even more preferably from 86 to 94% by weight, relative to the total weight of the thermochromic pigment composition.

Thus, the thermochromic pigment compositions of the present invention may comprise:

(A) from 1 to 10% by weight, preferably from 1 to 6% by weight and even more preferably from 2 to 4% by weight, of at least one organic electron-donating dye compound,

(B) from 1 to 20% by weight, preferably from 1 to 14% by weight and even more preferably from 4 to 10% by weight, of at least one electron-accepting compound, and

(C) from 70 to 98% by weight, preferably from 80 to 98% by weight and even more preferably from 86 to 94% by weight of at least one compound of formula (I).

According to a preferred embodiment, the thermally changeable pigment composition of the present invention comprises:

(A)2 to 4% by weight of at least one organic electron-donating dye compound,

(B)4 to 10% by weight of at least one electron-accepting compound, and

(C) from 86% to 94% by weight of at least one compound of the formula (I).

Advantageously, the thermochromic pigment compositions of the present invention have a color change hysteresis width (Δ H) after encapsulation ranging from 20 ℃ to 80 ℃, preferably from 30 ℃ to 80 ℃ and even more preferably from 40 ℃ to 70 ℃.

Some of the organic electron donating dye compounds (a) of note include conventionally known compounds such as diphenylmethane phthalide, phenylindolylphthalide, indolylphthalide, diphenylmethane azaphthalide, phenylindolylazabelphthalide, fluoran, styrylquinoline, and diazahodorhodamine lactone (diazahododiamine lactone), examples of which are as follows.

Thus, the organic electron donating dye compound (A) may be selected from 3- (4-diethylamino-2-ethoxyphenyl) -3- (1-ethyl-2-methylindol-3-yl) -4-azaphthalide (blue color 63, CAS number 69898-40-4), 3-bis (p-diethylaminophenyl) -6-diethylaminophthalate (CAS number 1552-42-7), 2 '-chloro-6' - (diethylamino) -3 '-methylfluorane (CAS number 21121-62-0), 6' - (diethylamino) -1',3' -dimethylfluorane (CAS number 21934-68-9), 2-chloro-6- (diethylamino) -fluorane (CAS number: 26567-23-7), 3-diethylaminobenzofluorane (CAS number: 26628-47-7), 3',6' -bis (diethylamino) -2- (4-nitrophenyl) spiro [ isoindole-1, 9' -xanthen ] -3-one (CAS number: 29199-09-5), 2-phenylamino-3-methyl-6-diethylaminofluorane (CAS number: 29512-49-0), 2' - (dibenzylamino) -6' - (diethylamino) fluorane (CAS number: 34372-72-0), 2- (2, 4-dimethylphenylamino) -3-methyl-6-diethylaminofluorane (CAS number: 36431-22-8), 3- (1, 2-dimethyl-3-indolyl) -3- [4- (diethylamino) -2-methylphenyl ] phthalide (CAS number: 36499-49-7), 3',6' -dimethoxyfluoran (CAS number: 36886-76-7), 3-bis- (1-butyl-2-methyl-indol-3-yl) -3H-isobenzofuran-1-one (Red 40, CAS number: 50292-91-6), 3-bis- (2-methyl-1-octyl-1H-indol-3-yl) -3H-isobenzofuran-1-one (CAS number: 50292-95-0), 2 '-anilino-6' - [ ethyl (p-tolyl) amino ] -3 '-methylspiro [ isobenzofuran-1 (3H),9' - [9H ] xanthene ] -3-one (CAS No.: 59129-79-2), 3- (N-ethyl-N-isopentylamino) -6-methyl-7-anilinofluorene (CAS No.: 70516-41-5), 3- [4[ (diethylamino) phenyl ] -3- (1-ethyl-2-methyl-1H-indol-3-yl) phthalide (CAS No.: 75805-17-3), 2'- (2-chloroanilino) -6' - (dibutylamino) fluoran (CAS No.: 82137-81-3), 2-phenylamino-3-methyl-6-dibutylaminofluoran (CAS number: 89331-94-2), 3- (1-butyl-2-methyl-1H-indol-3-yl) -6- (dimethylamino) -3- [4- (dimethylamino) phenyl ] -3- (1(3H) -isobenzofuranone (CAS number: 92453-31-1), 7- (4-diethylamino-2-hexyloxyphenyl) -7- (1-ethyl-2-methyl-1H-indol-3-yl) -7H-furo [3,4-b ] pyridin-5-one (blue 203, CAS number: 98660-18-5), 7-bis [4 (diethylamino) -2-ethoxyphenyl ] furo [3,4-b ] pyridin-5-one (CAS No.: 132467-74-4), N-dimethyl-4- [2- [2 (octyloxy) phenyl ] -6-phenyl-4-pyridinyl ] aniline (yellow CK37, CAS number: 144190-25-0), 3- (2, 2-bis (1-ethyl-2-methylindol-3-yl) vinyl) -3- (4-diethylaminophenyl) -phthalide (CAS number: 148716-90-9).

Preferably, the organic electron donating dye compound (A) is selected from the group consisting of 3- (4-diethylamino-2-ethoxyphenyl) -3- (1-ethyl-2-methylindol-3-yl) -4-azaphthalide (blue color 63, CAS number: 69898-40-4), 2'- (dibenzylamino) -6' - (diethylamino) fluoran (CAS number: 34372-72-0), N-dimethyl-4- [2- [2- (octyloxy) phenyl ] -6-phenyl-4-pyridyl ] aniline (yellow CK37, CAS number: 144190-25-0), 7- (4-diethylamino-2-hexyloxyphenyl) -7- (1-ethyl-2-methyl-1H) -indol-3-yl) -7H-furo [3,4-b ] pyridin-5-one (blue 203, CAS No.: 98660-18-5), 2- (2, 4-dimethylphenylamino) -3-methyl-6-diethylaminofluoran (black 15, CAS No.: 36431-22-8) and 3, 3-bis- (1-butyl-2-methyl-indol-3-yl) -3H-isobenzofuran-1-one (red 40, CAS No.: 50292-91-6).

Some notable electron-accepting compounds (B) include, but are not limited to, compounds having an active proton, such as compounds having a phenolic hydroxyl group (monophenol or polyphenol), derivatives thereof having a substituent (such as an alkyl group, an aryl group, an acyl group, an alkoxycarbonyl group, a carboxyl group, an ester thereof, an amine group, or a halogen atom), and condensed phenol resins such as bisphenol or triphenol.

In an aspect of the invention:

- "alkyl" means in C₁-C₂₀In, preferably at C₁-C₁₂Is more preferably at C₁-C₆And even more preferably at C₁-C₄A straight-chain or branched saturated hydrocarbon aliphatic group in (1). The term "branched" means that at least one lower alkyl group (such as methyl or ethyl) is carried by a linear alkyl chain. Some notable alkyl groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, t-butyl, and n-pentyl.

- "aryl" means any functional group or substituent derived from at least one aromatic ring; an aromatic ring corresponds to any monocyclic or polycyclic radical scheme containing a delocalized pi system, wherein each atom of the ring has an orbital p, the orbitals p overlapping one another; such notable aryl groups include phenyl, biphenyl, naphthalene, and anthracene. The aryl groups of the present invention preferably comprise from 4 to 12 carbon atoms, and even more preferably from 5 to 6 carbon atoms. Even more preferably, the aryl group of the present invention is phenyl.

Thus, the electron accepting compound (B) may be selected from 2, 2-bis- (4-hydroxy-3-methylphenyl) propane (bisphenol C, CAS number: 79-97-0), 4-hexyl-1, 3-dihydroxybenzene (4-hexylresorcinol, CAS number: 136-77-6), 4' -cyclohexylidenebisphenol (BPZ, CAS number: 843-55-0), 4' - (hexafluoroisopropylidene) diphenol (bisphenol AF, CAS number: 1478-61-1), 4' - (1-phenylethylidene) bisphenol (CAS number: 1571-75-1), 2' -dihydroxybiphenyl (CAS number: 1806-29-7), 4' -ethylidenebisphenol (CAS number: 2081-08-5), 4,4'- (1, 4-phenylenediisopropylidene) bisphenol (CAS number: 2167-51-3), 1, 1-bis (4-hydroxy-3-methylphenyl) cyclohexane (CAS number: 2362-14-3), 9-bis (4-hydroxyphenyl) fluorene (CAS number: 3236-71-3), 4' - (1, 3-phenylenediisopropylidene) bisphenol (CAS number: 13595-25-0), 1,1, 1-tris (4-hydroxyphenyl) ethane (CAS number: 27955-94-8), 4'- (2-ethylhexyl) diphenol (CAS number: 74462-02-5), α, α, α' -tris (4-hydroxyphenyl) -1-ethyl-4-isopropylbenzene (CAS number: 110726-28-8), 4- (1,1,3, 3-tetramethylbutyl) phenol (CAS number: 140-66-9), 4-hydroxydiphenyl ether (CAS number: 831-82-3), bis (2-hydroxy-1-naphthyl) methane (CAS number: 1096-84-0), 4- (methylsulfonyl) phenol (CAS number: 14763-60-1), 4-hydroxy-4 '-isopropoxyphenylsulfone (CAS number: 95235-30-6), 4' -dihydroxybiphenyl (CAS number: 92-88-6), 4-hydroxybiphenyl (CAS number: 92-69-3), p-hydroxycumene (CAS number: 99-89-8), 2, 4-dihydroxybenzophenone (CAS number: 131-56-6), Hydroquinone monomethyl ether (MEHQ, CAS number: 150-76-5), 3-N-pentadecylphenol (CAS number: 501-24-6), 4- (2-phenylisopropyl) phenol (CAS number: 599-64-4), 5-chloro-2 (2, 4-dichlorophenoxy) phenol (CAS number: 3380-34-5), N- (p-toluenesulfonyl) -N ' - (3- (-p-toluenesulfonyloxy) phenyl) urea (CAS number: 232938-43-1), 2-bis (3, 5-dibromo-4-hydroxyphenyl) propane (CAS number: 79-94-7), 4' -isopropylidene (CAS number: 80-05-7) and 4,4' -sulfonyldiphenol (BPS, CAS number: 80-09-1).

Preferably, the electron accepting compound (B) is selected from the group consisting of 2, 2-bis (4-hydroxy-3-methylphenyl) propane (bisphenol C, CAS number: 79-97-0), 4-hexyl-1, 3-dihydroxybenzene (4-hexylresorcinol, CAS number: 136-77-6), 4' -cyclohexylidenebisphenol (BPZ, CAS number: 843-55-0), 4' - (hexafluoroisopropylidene) diphenol (bisphenol AF, CAS number: 1478-61-1), 4' - (1-phenylethylidene) bisphenol (CAS number: 1571-75-1), 2' -dihydroxybiphenyl (CAS number: 1806-29-7), 4' - (1, 4-phenylenediisopropylidene) bisphenol (CAS number: 2167-51-3), 1, 1-bis (4-hydroxy-3-methylphenyl) cyclohexane (CAS number: 2362-14-3), 9-bis (4-hydroxyphenyl) fluorene (CAS number: 3236-71-3), 4' - (1, 3-phenylenediisopropylidene) bisphenol (CAS number: 13595-25-0), 1,1, 1-tris (4-hydroxyphenyl) ethane (CAS number: 27955-94-8), 4' - (2-ethylhexylidene) diphenol (CAS number: 74462-02-5), and α, α, α ' -tris (4-hydroxyphenyl) -1-ethyl-4-isopropylbenzene (CAS number: 110726-28-8).

The thermochromic pigment compositions of the present invention are prepared by: dissolving a compound (A) and a compound (B) in a compound (C) of formula (I) of the present invention; the compound is then agitated using an agitator such as a homogenizer or disperser until a homogeneous mixture is obtained.

Combining compound (A) and compound (B) with the compound of formula (I) of the present invention in this manner can be made into microcapsules. Thus, the thermochromic pigment compositions of the present invention are encapsulated in microcapsules to form thermochromic pigment microcapsules. Such thermochromic pigment microcapsules constitute a further object of the present invention. These thermochromic pigment microcapsules have advantageous properties in that they are resistant to mechanical stress, they are insoluble in water and therefore dispersible in water, and their rate of agglomeration is slow.

The melting temperature (or decolorization temperature T4) of the thermochromic pigment microcapsules of the present invention can vary from 20 ℃ to 80 ℃, preferably from 30 ℃ to 80 ℃ and even more preferably from 40 ℃ to 70 ℃.

The crystallization temperature (or re-coloration temperature T1) of the thermochromic pigment microcapsules of the present invention may vary from-40 ℃ to 20 ℃, preferably from-30 ℃ to 10 ℃ and even more preferably from-20 ℃ to 0 ℃.

The thermochromic pigment microcapsules of the present invention have an average diameter in the range of 0.5 to 30 μm, preferably 1 to 10 μm, and even more preferably 3 to 5 μm. This average diameter corresponds to d90 in volume and means that 90% of the volume of the microcapsules consists of microcapsules having a size in the indicated range. This average diameter can be determined by laser granulometry using a Zetasizer Nano ZS device from Malvern Instruments.

Microencapsulation methods used include, but are not limited to, conventional methods such as:

chemical processes based on the in situ formation of encapsulated microcapsules, for example by interfacial polymerization or polycondensation, these processes being preferred;

physicochemical processes, e.g. by phase separation or coacervation, solvent evaporation-extraction or thermal gelation (thermofusion) of emulsions, or

Mechanical processes, for example by atomization/drying (spray drying), droplet gelation or freezing or by coating on a fluidized bed (spraying).

The thermochromic pigment microcapsules of the present invention are advantageously based on aminoplast resins, and preferably on melamine resins, urea resins or benzoguanamine resins.

The thermochromic pigment microcapsules of the present invention are preferably prepared from melamine resins by in-situ polymerization.

Another object of the present invention is an ink composition comprising thermochromic pigment microcapsules according to the present invention.

The thermochromic pigment microcapsules of the present invention present in the ink composition comprise 5 to 50% by weight of the total weight of the ink composition.

Further, the ink composition of the present invention is mainly composed of water. Advantageously, the water represents from 40% to 80% by weight of the total weight of the ink composition.

The ink compositions of the present invention may also contain one or more water-miscible co-solvents. For example, the ink composition of the present invention may contain an organic or aqueous solvent, preferably an aqueous solvent.

Some notable solvents that may be added to the ink compositions of the present invention include water and water-miscible polar solvents, such as:

-an alcohol: c₁-C₁₅Straight or branched chain alcohols of (1), such as isopropanol, butanol, isobutanol, pentanol or benzyl alcohol; glycerol; diglycerin; a polyglycerol;

esters, such as ethyl acetate or propyl acetate;

carbonates, such as propylene carbonate or ethylene carbonate;

ketones, such as methyl isobutyl ketone (MIBC), acetone or cyclohexanone;

diols, such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, polyethylene glycol, ethylene glycol monomethyl ether, 3-butanediol and thiodiethylene glycol;

amides, such as dimethylacetamide or dimethylformamide; and

-mixtures thereof.

The solvent or solvents comprise 5 wt% to 20 wt% of the total weight of the ink composition.

The ink composition of the present invention may also contain one or more specific adjuvants, which may function differently depending on the final intended use. These applications may include inks for screen printing, offset printing, gravure printing, powder spraying, electrostatic coating, electroplating, roll coating, ink jet printing, and inks for writing instruments such as ball point pens, ink pens, markers, and colored pencils. The ink composition of the present invention may also be added to a thermoplastic resin composition or a thermosetting composition to form a mold member.

Some of the above noted adjuvants comprise:

rheology modifiers (shear diluents) capable of generating a gel effect, such as xanthan gum or arabic gum;

defoamers, such as modified aqueous silicone dispersions (from Synthron, Inc.))；

pH regulators, such as sodium hydroxide, triethanolamine;

surfactants, such as polyether polyols (TERGITOL from the Dow chemical company (DOW))^TM)；

Biocides, e.g. isothiazolinones (from Thor corporation))；

Preservatives, such as benzotriazole;

-a lubricant;

-a dispersant;

-a film-forming aid;

-a cross-linking agent;

-a wetting agent;

-a plasticizer;

-an antioxidant;

-a UV stabilizer.

The invention further relates to a writing instrument comprising the ink composition according to the invention. These means are generally constituted by a body containing the ink composition of the invention and possibly a friction element. The writing instrument according to the invention is advantageously selected from ballpoint pens, pencils, chalks and even more advantageously ballpoint pens with a friction-erasable ink. The friction element of the writing instrument is preferably an eraser.

Substrates to which the ink composition of the present invention can be applied are paper, fiber, leather, plastic, glass, metal, wood and concrete.

In addition to the above clauses, the present invention also includes other clauses which will become apparent from the following description relating to the synthesis of the compounds of formula (I) according to the present invention, the characterization of the compounds, and the use of the compounds as thermochromic modulators in thermochromic pigment compositions.

Examples of the invention

Example 1:

compounds (6), (7), (8), (9), (10) and (11) of the following formulae were prepared by:

by dissolving the reagents in acetonitrile at reflux (85 ℃) in the presence of potassium carbonate, according to the following synthesis scheme, for 7 days:

then, potassium carbonate was removed by filtration.

Or by dissolving the reagents in tert-butanol in the presence of sodium hydroxide at reflux (85 ℃) for 6 hours according to the following synthesis scheme:

the compounds (6), (7), (8), (9), (10) and (11) synthesized in this way were purified by successive recrystallization.

Synthesis of Compound (6):

20g of 3-n-pentadecylphenol (CAS number: 501-24-6), 16g of 1-bromo-3-phenylpropane (CAS number: 637-59-2) and 11g of calcium carbonate K₂CO₃(CAS number 584-08-7) was mixed in 100ml of acetonitrile and then heated at 85 ℃ for 7 days under reflux.

Removal of potassium carbonate K by filtration₂CO₃. The acetonitrile was then evaporated, and the resulting solid was recrystallized from 150ml of ethanol (purity: 95%). The reaction medium is heated at reflux until dissolution is complete and then cooled to room temperature until the product precipitates. The obtained solid was washed three times with 50ml of ethanol (purity: 95%).

Using PerkinElmer680/600S analysis of the product by gas chromatography (GPC) showed the product to be 96% pure.

Synthesis of Compound (7):

19.7g of 3-n-pentadecylphenol (CAS number: 501-24-6) was dissolved in 20ml of t-butanol, and then heated to 40 ℃ to produce a homogeneous mixture. 3.4g of sodium hydroxide (CAS number 1310-73-2) was diluted in 10ml of distilled water and then added to the reaction medium. After stirring for 15 minutes, 10g of (2-bromoethyl) benzene (CAS number: 103-63-9) are added to the mixture and the reaction medium is heated at 80 ℃ for 6 hours.

The solid product was recovered by recrystallization and filtration, and then purified by three successive recrystallizations in 200ml of ethanol.

Using PerkinElmer680/600S analysis of the product by gas chromatography (GPC) showed the product to be 96% pure.

Synthesis of Compound (8):

20g of 3-n-pentadecylphenol (CAS number: 501-24-6), 16g of beta-bromophenetole (CAS number: 637-59-2) and 11g of calcium carbonate K₂CO₃(CAS number 584-08-7) was mixed in 100ml of acetonitrile and then heated at 85 ℃ for 7 days under reflux.

Removal of potassium carbonate K by filtration₂CO₃. The acetonitrile was then evaporated, and the resulting solid was recrystallized from 150ml of ethanol (purity: 95%). The reaction medium is heated at reflux until dissolution is complete and then cooled to room temperature until the product precipitates. The obtained solid was washed three times with 50ml of ethanol (purity: 95%).

Using PerkinElmer680/600S analysis of the product by gas chromatography (GPC) showed the product to be 99% pure.

Synthesis of Compound (9):

17g of 3-n-pentadecylphenol (CAS number: 501-24-6) was dissolved in 100ml of t-butanol, and then heated to 40 ℃ to produce a homogeneous mixture. 2.9g of sodium hydroxide (CAS number 1310-73-2) are diluted in 10ml of distilled water and then added to the reaction medium. After stirring for 15 minutes, 10g of 3-phenoxypropane (CAS number: 588-63-6) are added to the mixture and the reaction medium is heated at 80 ℃ for 6 hours.

The solid product was recovered by recrystallization and filtration, and then purified by three successive recrystallizations in 150ml of ethanol.

Using PerkinElmer680/600S analysis of the product by gas chromatography (GPC) showed the product to beThe purity of (2) was 99%.

Synthesis of Compound (10):

15.8g of 3-n-pentadecylphenol (CAS number: 501-24-6) was dissolved in 100ml of t-butanol, and then heated to 40 ℃ to produce a homogeneous mixture. 2.8g of sodium hydroxide (CAS number 1310-73-2) are diluted in 10ml of distilled water and then added to the reaction medium. After stirring for 15 minutes, 10g of 4-bromobutyl phenyl ether (CAS number: 1200-03-9) are added to the mixture and the reaction medium is heated at 80 ℃ for 6 hours.

The solid product was recovered by recrystallization and filtration, and then purified by three successive recrystallizations in 150ml of ethanol.

Using PerkinElmer680/600S analysis of the product by gas chromatography (GPC) showed the product to be 98% pure.

Synthesis of Compound (11):

14g of 3-n-pentadecylphenol (CAS number: 501-24-6) was dissolved in 20ml of t-butanol, and then heated to 40 ℃ to produce a homogeneous mixture. 2.5g of sodium hydroxide (CAS number 1310-73-2) are diluted in 10ml of distilled water and then added to the reaction medium. After stirring for 15 minutes, 10g of 6-phenoxypropane (CAS number: 57795-97-2) are added to the mixture and the reaction medium is heated at 80 ℃ for 8 hours.

The solid product was recovered by recrystallization and filtration, and then purified by three successive recrystallizations in 150ml of ethanol.

Using PerkinElmer680/600S analysis of the product by gas chromatography (GPC) showed the product to be 96% pure.

Measured by Differential Scanning Calorimetry (DSC) using a TA Instruments Q20 instrument at a heating/cooling rate of +/-20 deg.C/min over a temperature range of-50 deg.C to 100 deg.CThe melting temperatures T of the resulting compounds (6), (7), (8), (9), (10) and (11)_FUS. The measured temperatures are shown in table 1 below.

Table 1:

example 2:

compounds (1), (2), (3), (4), (5), (12), (13), (14), (15) and (16) of the following formula were prepared by:

-from carboxylic acids using alcohols with melting point below 60 ℃ as solvent and p-toluenesulfonic acid as reaction catalyst. The mixture is heated under slight vacuum to a temperature between 120 ℃ and 150 ℃ in order to be able to remove the water and thus shift the equilibrium to the synthesis of the compound of formula (I).

The resulting compound of formula (I) is purified by recrystallization using a single alcohol.

-prepared from an alcohol by dissolving it in Tetrahydrofuran (THF) at a temperature between 0 ℃ and 20 ℃ with triethylamine as catalyst. The acid chloride was then added slowly dropwise over 30 minutes. The mixture was then heated to room temperature (25 ℃) with stirring for 2 hours.

The resulting compounds (1), (2), (3), (4), (5) (12), (13), (14), (15) and (16) were purified by recrystallization.

Synthesis of Compound (1):

17.8g of 3-pentadecylphenol (CAS number: 501-24-6) and 5.8g of triethylamine (CAS number: 121-44-8) were dissolved in 250ml of tetrahydrofuran (CAS number: 109-99-9). The reaction medium is kept at room temperature and then rendered inert by the addition of nitrogen. 10g of phenoxyacetic acid chloride (CAS number: 701-99-5) was added dropwise over a period of 15 minutes. After the addition is complete, the reaction medium is stirred at room temperature for 30 minutes.

The reaction medium is then extracted with 100ml of ethyl acetate. The organic phase is recovered and washed three times with 100ml of water. The organic phase was then dried over sodium sulfate and the solvent was evaporated.

The product was recrystallized twice from isopropanol.

Using PerkinElmer680/600S analysis of the product by gas chromatography (GPC) showed the product to be 95% pure.

Synthesis of Compound (2):

18g of 3-pentadecylphenol (CAS number: 501-24-6) and 6.5g of triethylamine (CAS number: 121-44-8) were dissolved in 250ml of tetrahydrofuran (CAS number: 109-99-9). The reaction medium is kept at room temperature and then rendered inert by the addition of nitrogen. 10g of trans-3-phenylpropionyl chloride (CAS number: 102-92-1) diluted in 10ml of tetrahydrofuran was added dropwise over 15 minutes. After the addition is complete, the reaction medium is stirred at room temperature for 30 minutes.

The reaction medium is then extracted with 150ml of ethyl acetate. The organic phase is recovered and washed three times with 150ml of water. The organic phase was then dried over sodium sulfate and the solvent was evaporated.

The product was recrystallized twice from ethanol.

Using PerkinElmer680/600S analysis of the product by gas chromatography (GPC) showed the product to be 90% pure.

Synthesis of Compound (3):

under reduced pressure (400 mbar), 20g of 3-pentadecylphenol (CAS number: 501-24-6), 19.7g of 3-phenylpropionic acid (CAS number: 501-52-0) and 200mg of p-toluenesulfonic acid monohydrate (APTS) (CAS number: 6192-52-5) were mixed and heated at 140 ℃ for 3 days.

The reaction medium was purified by adding 50ml of ethanol (purity: 95%) and then heated under reflux until dissolution was complete. The reaction medium is then cooled to room temperature until the product precipitates. The obtained solid was washed three times with 30ml of ethanol (purity: 95%).

The product was recrystallized twice from isopropanol.

Using PerkinElmer680/600S analysis of the product by gas chromatography (GPC) showed the product to be 83% pure.

Synthesis of Compound (4):

under reduced pressure (600 mbar), 20g of 3-pentadecylphenol (CAS number: 501-24-6), 30g of 3, 3-phenylpropionic acid (CAS number: 606-83-7) and 200mg of p-toluenesulfonic acid monohydrate (APTS) (CAS number: 6192-52-5) were mixed and heated at 160 ℃ for 3 days.

The reaction medium is purified by addition of 150ml of ethanol (purity: 95%) and then heated under reflux until dissolution is complete. The reaction medium is then cooled to room temperature until the product precipitates. The obtained solid was washed three times with 30ml of ethanol (purity: 95%).

Using PerkinElmer680/600S analysis of the product by gas chromatography (GPC) showed the product to be 95% pure.

Synthesis of Compound (5):

13.8g of 3-pentadecylphenol (CAS number: 501-24-6) and 5.0g of triethylamine (CAS number: 121-44-8) were dissolved in 150ml of tetrahydrofuran (CAS number: 109-99-9). The reaction medium is kept at room temperature and made inert by addition of nitrogen. 10.4g of diphenylphenylacetyl chloride (CAS number: 1871-76-7) diluted in 15ml of tetrahydrofuran was added dropwise over 15 minutes. After the addition is complete, the reaction medium is stirred at room temperature for 30 minutes.

The reaction medium is then extracted with 100ml of ethyl acetate. The organic phase is recovered and washed three times with 150ml of water. The organic phase was then dried over sodium sulfate and the solvent was evaporated.

The product was recrystallized twice using ethanol cooled to-20 ℃.

Using PerkinElmer680/600S analysis of the product by gas chromatography (GPC) showed the product to be 86% pure.

Synthesis of Compound (12):

38.9g of 3-pentadecylphenol (CAS number: 501-24-6) and 6.8g of triethylamine (CAS number: 121-44-8) were dissolved in 250ml of tetrahydrofuran (CAS number: 109-99-9). The reaction medium is kept at room temperature and made inert by addition of nitrogen. 10g of succinic acid chloride (CAS number: 543-20-4) was added dropwise over a period of 15 minutes. After the addition is complete, the reaction medium is stirred at room temperature for 30 minutes.

Then, the resulting product was extracted with 100ml of ethyl acetate. The organic phase is recovered and washed three times with 150ml of water. The organic phase was then dried over sodium sulfate and the solvent was evaporated.

The product was recrystallized twice from isopropanol.

Using PerkinElmer680/600S analysis of the product by gas chromatography (GPC) showed the product to be 94% pure.

Synthesis of Compound (13):

33.1g of 3-pentadecylphenol (CAS number: 501-24-6) and 8.1g of triethylamine (CAS number: 121-44-8) were dissolved in 250ml of tetrahydrofuran (CAS number: 109-99-9). The reaction medium is kept at room temperature and made inert by addition of nitrogen. 10g of adipic acid chloride (CAS number: 111-50-2) was added dropwise over 15 minutes. After the addition is complete, the reaction medium is stirred at room temperature for 30 minutes.

Then, the resulting product was extracted with 100ml of ethyl acetate. The organic phase is recovered and washed three times with 150ml of water. The organic phase was then dried over sodium sulfate and the solvent was evaporated.

The product was recrystallized twice from isopropanol.

Using PerkinElmer680/600S analysis of the product by gas chromatography (GPC) showed the product to be 87% pure.

Synthesis of Compound (14):

15.9g of 3-pentadecylphenol (CAS number: 501-24-6) and 5.8g of triethylamine (CAS number: 121-44-8) were dissolved in 250ml of tetrahydrofuran (CAS number: 109-99-9). The reaction medium is kept at room temperature and made inert by addition of nitrogen. 10g of suberic acid chloride (CAS number: 10027-07-3) was added dropwise over a period of 15 minutes. After the addition is complete, the reaction medium is stirred at room temperature for 30 minutes.

Then, the resulting product was extracted with 100ml of ethyl acetate. The organic phase is recovered and washed three times with 150ml of water. The organic phase was then dried over sodium sulfate and the solvent was evaporated.

The product was recrystallized twice from isopropanol.

Using PerkinElmer680/600S analysis of the product by gas chromatography (GPC) showed the product to be 96% pure.

Synthesis of Compound (15):

20g of 3-pentadecylphenol (CAS number: 501-24-6) and 7.2g of triethylamine (CAS number: 121-44-8) were dissolved in 250ml of tetrahydrofuran (CAS number: 109-99-9). The reaction medium is cooled to 5 ℃ and maintained at this temperature in an ice bath. The reaction medium is rendered inert by the addition of nitrogen. 7.9g of sebacoyl chloride (CAS number: 111-19-3) was added dropwise over 15 minutes. The reaction medium is then stirred at room temperature for 2 hours.

Then, the resulting product was extracted with 200ml of ethyl acetate. The organic phase is recovered and washed three times with 100ml of water. The organic phase was then dried over sodium sulfate and the solvent was evaporated.

Using PerkinElmer680/600S analysis of the product by gas chromatography (GPC) showed the product to be 90% pure.

Synthesis of Compound (16):

22.7g of 3-pentadecylphenol (CAS number: 501-24-6) and 8.3g of triethylamine (CAS number: 121-44-8) were dissolved in 250ml of tetrahydrofuran (CAS number: 109-99-9). The reaction medium is kept at room temperature and made inert by addition of nitrogen. 10g of lauric acid chloride (CAS number: 4834-98-4) was added dropwise over a period of 15 minutes. After the addition is complete, the reaction medium is stirred at room temperature for 30 minutes.

Then, the resulting product was extracted with 100ml of ethyl acetate. The organic phase is recovered and washed three times with 150ml of water. The organic phase was then dried over sodium sulfate and the solvent was evaporated.

The product was recrystallized twice from isopropanol.

Using PerkinElmer680/600S analysis of the product by gas chromatography (GPC) showed the product to be 94% pure.

The melting temperatures of the obtained compounds (1), (2), (3), (4) (5), (12), (13), (14), (15) and (16) were measured by Differential Scanning Calorimetry (DSC) using a TA Instruments Q20 apparatus at a heating/cooling rate of +/-20 ℃/min in the temperature range of-50 ℃ to 100 ℃. The measured temperatures are shown in table 2 below.

Table 2:

example 3:

preparation of thermochromic pigment compositions:

a thermochromic pigment composition was prepared by mixing 2.2 parts by weight of 3- (4-diethylamino-2-ethoxyphenyl) -3- (1-ethyl-2-methylindol-3-yl) -4-azaphthalide (compound (A), CAS No.: 69898-40-4), 2.2 parts by weight of 4,4' - (hexafluoroisopropylidene) diphenol (compound (B1), CAS No.: 1478-61-1), 2.2 parts by weight of 2, 2-bis (4-hydroxy-3-methylphenyl) propane (compound (B2), CAS No.: 79-97-0), and 93.4 parts by weight of previously prepared compound (4) (compound (C)). The resulting mixture was heated at a temperature of 110 ℃ for 45 minutes with stirring until the compounds (A), (B1) and (B2) had completely dissolved in the compound (C).

Preparation of thermochromic pigment microcapsules:

at pH 4, 7.5 parts by weight of an aqueous solution of maleic anhydride copolymer and methyl vinyl ether (copolymer in 33% by weight solution) was neutralized with 9.2 parts by weight of an aqueous solution of sodium hydroxide (1.0M solution). Diluting the solution with 41.0 parts by weight of water and homogenizing at least 15m.s^-1The speed of (a) emulsify the mixture. 25.6 parts by weight of the previously prepared thermochromic pigment composition was added and the resulting emulsion was kept at a temperature of 85 ℃ for 30 minutes. Then, 16.7 parts by weight of melamine-formaldehyde prepolymer (prepolymer in 50% by weight aqueous solution) was added dropwise to the mixture. The reaction medium is then heated to a temperature of 90 ℃ and at least 15m.s^-1Mixed for 4 hours.

A slurry consisting of thermochromic pigment microcapsules dispersed in an aqueous solvent was obtained, the diameter d90 of the microcapsules being 4.2 μm, the diameter being determined with the Zetasizer Nano ZS system from marvens instruments under 632nm irradiation.

The obtained thermochromic pigment microcapsule has the color change characteristic of changing from blue to colorless at a temperature of above 58 ℃, and has a color hysteresis effect.

Example 4:

preparation of thermochromic pigment compositions:

a thermochromic pigment composition was prepared by mixing 3 parts by weight of 3- (4-diethylamino-2-ethoxyphenyl) -3- (1-ethyl-2-methylindol-3-yl) -4-azaphthalide (compound (A), CAS No.: 69898-40-4), 2.5 parts by weight of 4,4' - (hexafluoroisopropylidene) diphenol (compound (B1), CAS No.: 1478-61-1), 2.5 parts by weight of 2, 2-bis (4-hydroxy-3-methylphenyl) propane (compound (B2), CAS No.: 79-97-0), and 92 parts by weight of the previously synthesized compound (8) (compound (C)).

The resulting mixture was heated at a temperature of 110 ℃ for 1 hour with stirring until the compounds (A), (B1) and (B2) had completely dissolved in the compound (C).

Preparation of thermochromic pigment microcapsules:

at pH 4, 7.5 parts by weight of an aqueous solution of maleic anhydride copolymer and methyl vinyl ether (copolymer in 33% by weight solution) was neutralized with 8.7 parts by weight of an aqueous solution of sodium hydroxide (1.0M solution). Diluting the solution with 42.6 parts by weight of water and homogenizing at least 15m.s^-1The speed of (a) emulsify the mixture. 25.2 parts by weight of the previously prepared thermochromic pigment composition is added and the resulting emulsion is kept at a temperature of 90 ℃ for 30 minutes. Then, 16.0 parts by weight of melamine-formaldehyde prepolymer (aqueous solution of prepolymer at 50% by weight) was added dropwise to the mixture. The reaction medium is then heated to a temperature of 90 ℃ and at least 15m.s^-1Mixed for 4 hours.

A slurry consisting of thermochromic pigment microcapsules dispersed in an aqueous solvent was obtained, the diameter d90 of the microcapsules being 4.6 μm, the diameter being determined with the Zetasizer Nano ZS system from marvens instruments under 632nm irradiation.

The obtained thermochromic pigment microcapsule has a color change characteristic of changing from blue to colorless at 71 ℃ or higher, and has a color hysteresis effect.

Example 5:

preparation of thermochromic pigment compositions:

a thermochromic pigment composition was prepared by mixing 2.2 parts by weight of 3- (4-diethylamino-2-ethoxyphenyl) -3- (1-ethyl-2-methylindol-3-yl) -4-azaphthalide (compound (A), CAS No.: 69898-40-4), 2.2 parts by weight of 4,4' - (hexafluoroisopropylidene) diphenol (compound (B1), CAS No.: 1478-61-1), 2.2 parts by weight of 2, 2-bis (4-hydroxy-3-methylphenyl) propane (compound (B2), CAS No.: 79-97-0), and 93.4 parts by weight of the previously synthesized dense compound (15) (compound (C)).

The resulting mixture was heated at a temperature of 110 ℃ for 30 minutes with stirring until the compounds (A), (B1) and (B2) had completely dissolved in the compound (C).

Preparation of microencapsulated thermochromic pigments:

at pH 4, 9.4 parts by weight of an aqueous solution of maleic anhydride copolymer and methyl vinyl ether (copolymer-33% by weight solution) was neutralized with 7.6 parts by weight of an aqueous solution of sodium hydroxide (1.0M solution). Diluting the solution with 39.6 parts by weight of water and homogenizing at least 15m.s^-1The speed of (a) emulsify the mixture. 26.7 parts by weight of the previously prepared thermochromic pigment composition is added and the resulting emulsion is kept at a temperature of 80 ℃ for 30 minutes. Then, 16.7 parts by weight of melamine-formaldehyde prepolymer (prepolymer in 50% by weight aqueous solution) was added dropwise to the mixture. The reaction medium is then heated to a temperature of 90 ℃ and at least 15m.s^-1Mixed for 4 hours.

A slurry consisting of thermochromic pigment microcapsules dispersed in an aqueous solvent was obtained, the diameter d90 of the microcapsules being 3.7 μm, the diameter being determined with the Zetasizer Nano ZS system from marvens instruments under 632nm irradiation.

The obtained thermochromic pigment microcapsule has a color change characteristic of changing from blue to colorless at 55 ℃ or higher, and has a color hysteresis effect.

Preparation of ink composition:

10.8 parts by weight of glycerol (co-solvent) are heated to a temperature of 30 ℃ with stirring by a blade. Then 0.2 parts by weight of benzotriazole (preservative) and 0.2 parts by weight of an aqueous solution comprising 2.5% by weight of 1, 2-benzisothiazolin-3-one and 2.5% by weight of 2-methyl-4-isothiazolin-3-one (biocide), 0.5 parts by weight of an aqueous dispersion of a polysiloxane copolymer (aqueous dispersion with 50% by weight of polymer) (defoamer) and 0.5 parts by weight of a polyether polyol (surfactant) are added. The mixture was stirred until the additives were completely dissolved. 0.5 parts by weight of xanthan gum (rheology modifier) was slowly added for 15 minutes. After the rheology modifier was dispersed, 26.8 parts by weight of distilled water was added. The resulting ink composition was stirred for 3 hours, and then 60 parts by weight of the aqueous dispersion of the thermochromic pigment microcapsules prepared above (30% by weight of the aqueous dispersion of thermochromic pigment microcapsules) was added. The pH of the ink composition was adjusted to pH 8 with 0.5 parts by weight of triethanolamine. The blue ink is then dispensed at a dispenser of at least 15m.s^-1The speed of (2) was dispersed for 30 minutes. The ink composition was degassed under reduced pressure before being injected into the cartridge.

Example 6:

preparation of thermochromic pigment compositions:

a thermochromic pigment composition was prepared by mixing 2.3 parts by weight of 3- (4-diethylamino-2-ethoxyphenyl) -3- (1-ethyl-2-methylindol-3-yl) -4-azaphthalide (compound (A), CAS No.: 69898-40-4), 1.9 parts by weight of 4,4' - (hexafluoroisopropylidene) diphenol (compound (B1), CAS No.: 1478-61-1), 1.9 parts by weight of 2, 2-bis (4-hydroxy-3-methylphenyl) propane (compound (B2), CAS No.: 79-97-0), and 93.9 parts by weight of the previously synthesized compound (2) (compound (C)). The resulting mixture was heated at a temperature of 110 ℃ for 45 minutes with stirring until the compounds (A), (B1) and (B2) had completely dissolved in the compound (C).

Preparation of thermochromic pigment microcapsules:

at pH 4.5, 9.3 parts by weight of an aqueous solution of maleic anhydride copolymer and methyl vinyl ether (copolymer-27% by weight solution) was neutralized with 16.3 parts by weight of an aqueous solution of sodium hydroxide (1.0M solution). Diluting the solution with 27.6 parts by weight of water and homogenizing at least 15m.s^-1The speed of (a) emulsify the mixture. 27.0 parts by weight of the previously prepared thermochromic pigment composition were added and the resulting emulsion was kept at a temperature of 85 ℃ for 30 minutes. Then, 19.8 parts by weight of melamine-formaldehyde prepolymer (prepolymer in 50% by weight aqueous solution) was added dropwise to the mixture. The reaction medium is then heated to a temperature of 90 ℃ and at least 15m.s^-1Mixed for 4 hours.

A slurry consisting of thermochromic pigment microcapsules dispersed in an aqueous solvent was obtained, the diameter d90 of the microcapsules being 2.8 μm, the diameter being determined with the Zetasizer Nano ZS system from marvens instruments under 632nm irradiation.

The obtained thermochromic pigment microcapsule has a color change characteristic of changing from blue to colorless at 54 ℃ or higher, and has a color hysteresis effect.

Preparation of ink composition:

10.5 parts by weight of glycerol (co-solvent) are heated to a temperature of 30 ℃ with stirring by a blade. Then 0.2 parts by weight of benzotriazole (preservative) and 0.2 parts by weight of an aqueous solution comprising 2.5% by weight of 1, 2-benzisothiazolin-3-one and 2.5% by weight of 2-methyl-4-isothiazolin-3-one (biocide), 0.5 parts by weight of an aqueous dispersion of a polysiloxane copolymer (aqueous dispersion with 50% by weight of polymer) (defoamer) and 0.8 parts by weight of a polyether polyol (surfactant) were added. The mixture was stirred until the additives were completely dissolved. 0.5 parts by weight of xanthan gum (rheology modifier) was slowly added for 15 minutes. After the rheology modifier was dispersed, 26.8 parts by weight of distilled water was added. The resulting ink composition was stirred for 3 hours, and then 60 parts by weight of the aqueous dispersion of the thermochromic pigment microcapsules prepared above (30% by weight of the aqueous dispersion of thermochromic pigment microcapsules) was added. Ink composition with 0.5 weight part of triethanolamineThe pH of (a) was adjusted to pH 8. The blue ink is then dispensed at a dispenser of at least 15m.s^-1The speed of (2) was dispersed for 30 minutes. The ink composition was degassed under reduced pressure prior to injection into the cartridge.

Example 7:

preparation of thermochromic pigment compositions:

a thermochromic pigment composition was prepared by mixing 2.2 parts by weight of 3- (4-diethylamino-2-ethoxyphenyl) -3- (1-ethyl-2-methylindol-3-yl) -4-azaphthalide (compound (A), CAS No.: 69898-40-4), 2.0 parts by weight of 4,4' - (hexafluoroisopropylidene) diphenol (compound (B1), CAS No.: 1478-61-1), 2.0 parts by weight of 2, 2-bis (4-hydroxy-3-methylphenyl) propane (compound (B2), CAS No.: 79-97-0), and 93.8 parts by weight of the previously synthesized compound (9) (compound (C)). The resulting mixture was heated at a temperature of 110 ℃ for 45 minutes with stirring until the compounds (A), (B1) and (B2) had completely dissolved in the compound (C).

Preparation of thermochromic pigment microcapsules:

at pH 4.5, 9.0 parts by weight of an aqueous solution of maleic anhydride copolymer and methyl vinyl ether (copolymer-27% by weight solution) was neutralized with 15.7 parts by weight of an aqueous solution of sodium hydroxide (1.0M solution). Diluting the solution with 28.1 parts by weight of water and homogenizing at least 15m.s^-1The speed of (a) emulsify the mixture. 28.1 parts by weight of the previously prepared thermochromic pigment composition were added and the resulting emulsion was kept at a temperature of 85 ℃ for 30 minutes. Then, 19.1 parts by weight of melamine-formaldehyde prepolymer (prepolymer in 50% by weight aqueous solution) was added dropwise to the mixture. The reaction medium is then heated to a temperature of 90 ℃ and at least 15m.s^-1Mixed for 4 hours.

A slurry consisting of thermochromic pigment microcapsules dispersed in an aqueous solvent was obtained, the diameter d90 of the microcapsules being 4.2 μm, the diameter being determined with the Zetasizer Nano ZS system from marvens instruments under 632nm irradiation.

The obtained thermochromic pigment microcapsule has the color change characteristic of changing from blue to colorless at the temperature of above 56 ℃, and has a color hysteresis effect.

Example 8:

preparation of thermochromic pigment compositions:

a thermochromic pigment composition was prepared by mixing 2.2 parts by weight of 3- (4-diethylamino-2-ethoxyphenyl) -3- (1-ethyl-2-methylindol-3-yl) -4-azaphthalide (compound (A), CAS No.: 69898-40-4), 2.0 parts by weight of 4,4' - (hexafluoroisopropylidene) diphenol (compound (B1), CAS No.: 1478-61-1), 2.0 parts by weight of 2, 2-bis (4-hydroxy-3-methylphenyl) propane (compound (B2), CAS No.: 79-97-0), and 93.8 parts by weight of the previously synthesized compound (14) (compound (C)). The resulting mixture was heated at a temperature of 110 ℃ for 45 minutes with stirring until the compounds (A), (B1) and (B2) had completely dissolved in the compound (C).

Preparation of thermochromic pigment microcapsules:

at pH 4.5, 9.4 parts by weight of an aqueous solution of maleic anhydride copolymer and methyl vinyl ether (copolymer-27% by weight solution) was neutralized with 16.2 parts by weight of an aqueous solution of sodium hydroxide (1.0M solution). Diluting the solution with 27.5 parts by weight of water and homogenizing at least 15m.s^-1The speed of (a) emulsify the mixture. 27.3 parts by weight of the previously prepared thermochromic pigment composition were added and the resulting emulsion was kept at a temperature of 85 ℃ for 30 minutes. Then, 19.6 parts by weight of melamine-formaldehyde prepolymer (aqueous solution of prepolymer at 50% by weight) was added dropwise to the mixture. The reaction medium is then heated to a temperature of 90 ℃ and at least 15m.s^-1Mixed for 4 hours.

A slurry consisting of thermochromic pigment microcapsules dispersed in an aqueous solvent was obtained, the diameter d90 of the microcapsules being 3.2 μm, the diameter being determined with the Zetasizer Nano ZS system from marvens instruments under 632nm irradiation.

The obtained thermochromic pigment microcapsule has a color change characteristic of changing from blue to colorless at 55 ℃ or higher, and has a color hysteresis effect.

Preparation of ink composition:

in-use paddle10.3 parts by weight of glycerol (co-solvent) were heated to a temperature of 30 ℃ with stirring. Then 0.2 parts by weight of benzotriazole (preservative) and 0.2 parts by weight of an aqueous solution comprising 2.5% by weight of 1, 2-benzisothiazolin-3-one and 2.5% by weight of 2-methyl-4-isothiazolin-3-one (biocide), 0.5 parts by weight of an aqueous dispersion of a polysiloxane copolymer (aqueous dispersion with 50% by weight of polymer) (defoamer) and 0.5 parts by weight of a polyether polyol (surfactant) are added. The mixture was stirred until the additives were completely dissolved. 0.5 parts by weight of xanthan gum (rheology modifier) was slowly added for 15 minutes. After the rheology modifier was dispersed, 26.8 parts by weight of distilled water was added. The resulting ink composition was stirred for 3 hours, and then 60 parts by weight of the aqueous dispersion of the thermochromic pigment microcapsules prepared above (30% by weight of the aqueous dispersion of thermochromic pigment microcapsules) was added. The pH of the ink composition was adjusted to pH 8 with 1 part by weight of NaOH. The blue ink is then dispensed at a dispenser of at least 15m.s^-1The speed of (2) was dispersed for 30 minutes. The ink composition was degassed under reduced pressure before being injected into the cartridge.

Example 9:

preparation of thermochromic pigment compositions:

a thermochromic pigment composition was prepared by mixing 2.2 parts by weight of 3- (4-diethylamino-2-ethoxyphenyl) -3- (1-ethyl-2-methylindol-3-yl) -4-azaphthalide (compound (A), CAS No.: 69898-40-4), 2.0 parts by weight of 4,4' - (hexafluoroisopropylidene) diphenol (compound (B1), CAS No.: 1478-61-1), 2.0 parts by weight of 2, 2-bis (4-hydroxy-3-methylphenyl) propane (compound (B2), CAS No.: 79-97-0), and 93.8 parts by weight of the previously synthesized compound (16) (compound (C)). The resulting mixture was heated at a temperature of 110 ℃ for 45 minutes with stirring until the compounds (A), (B1) and (B2) had completely dissolved in the compound (C).

Preparation of thermochromic pigment microcapsules:

at pH 4.5, 9.3 parts by weight of an aqueous solution of maleic anhydride copolymer and methyl vinyl ether (copolymer-27% by weight solution) was neutralized with 16.0 parts by weight of an aqueous solution of sodium hydroxide (1.0M solution). By using27.7 parts by weight of water and using a homogenizer at least 15m.s^-1The speed of (a) emulsify the mixture. 27.1 parts by weight of the previously prepared thermochromic pigment composition were added and the resulting emulsion was kept at a temperature of 85 ℃ for 30 minutes. Then, 19.9 parts by weight of melamine-formaldehyde prepolymer (aqueous solution of prepolymer at 50% by weight) was added dropwise to the mixture. The reaction medium is then heated to a temperature of 90 ℃ and at least 15m.s^-1Mixed for 4 hours.

A slurry consisting of thermochromic pigment microcapsules dispersed in an aqueous solvent was obtained, the diameter d90 of the microcapsules being 3.1 μm, the diameter being determined with the Zetasizer Nano ZS system from marvens instruments under 632nm irradiation.

The obtained thermochromic pigment microcapsule has the color change characteristic of changing from blue to colorless at a temperature of above 58 ℃, and has a color hysteresis effect.

Determination of the decolorization and recoloring temperatures of the thermochromic pigment microcapsules prepared in examples 3,4, 5, 6, 7, 8 and 9:

the transition temperature of the thermochromic pigment microcapsules obtained was measured by Differential Scanning Calorimetry (DSC) using a TA Instruments Q20 in the temperature range-50 ℃ to 100 ℃ with a heating/cooling rate of +/-20 ℃/min. The measured temperatures are shown in table 3 below.

Table 3: transition temperatures of the thermochromic pigment microcapsules prepared in examples 3,4, 5, 6, 7, 8 and 9:

the measured transition temperatures were as follows:

t1: the temperature of the complete re-coloration is,

t2: the temperature of the part to be re-colored,

t3: the temperature of the partial decolorization is controlled,

t4: the temperature of the complete decolorization is controlled,

Δ H hysteresis range T_G-T_H。