[0001]The present invention relates to an aqueous ink
10 composition for reversibly thermochromic writing instrument, and a refill and an aqueous ballpoint pen incorporating the aqueous ink composition for reversibly thermochromic writing instrument. More specifically, the present invention relates to an aqueous ink composition for reversibly thermochromic writing instrument
15 which exhibits reversible thermochromism between coloring and decoloring with showing a large hysteresis characteristic upon changing temperature and keeps either of the colored state and decolored state alternately and reversibly even after removal of application of the heat or cold required for the discoloration, and
20 to a refill and an aqueous ballpoint pen incorporating the aqueous ink composition for reversibly thermochromic writing instrument.
Background Art [0002]
25 An aqueous ink composition for reversibly thermochromic
writing instrument that can form a handwriting and the like that can memorize and keep alternately states before and after a color change in a certain temperature range such as an ordinary temperature region, and a writing instrument incorporating the
30 aqueous ink composition for reversibly thermochromic writing instrument have been heretofore proposed. A wide variety of such writing instruments have been proposed, such as a ballpoint pen, a marking pen, a fountain pen, and a solid writing material. In a writing instrument incorporating the aqueous ink
35 composition for reversibly thermochromic writing instrument, thermochromism is important performance; however, similarly to
2

a general writing instrument, it is desired that various
performances such as writability, handwriting density, and light
resistance are also high. However, since a colorant used in a
thermochromic composition is relatively special, it is difficult to
5 obtain excellent properties even if the same materials and
blending ratios as those of general ink compositions are employed. In particular, when a microcapsule pigment in which a reversibly thermochromic composition is encapsulated in a microcapsule is used, it may be necessary to increase the blending ratio of a
10 pigment in order to achieve a high density, and it is difficult to
apply a conventional ink composition ratio as it is. [0003]
In particular, although the aqueous ink composition for reversibly thermochromic writing instrument contains an organic
15 material as a reversibly thermochromic colorant, an interaction
with other organic materials contained in the composition may occur. For example, aggregation of organic colorant particles, an increase in viscosity of the composition, a decrease in the handwriting density, deterioration in the writability, and the like
20 may occur.
Citation List
Patent Literature
[0004]
25 Patent Literature 1: JP 2009-292878 A
Summary of Invention
Technical Problem
[0005]
30 An object of the present invention is to solve problems in
an aqueous ink composition for writing instrument containing a reversibly thermochromic colorant, and to simultaneously improve various properties.
35 Solution to Problem
[0006]
3

A reversibly thermochromic aqueous ink composition according to the present invention includes
a reversibly thermochromic microcapsule pigment in which
a reversibly thermochromic composition including (a) an
5 electron-donating color-developing organic compound, (b) an
electron-accepting compound, and (c) a reaction medium to
determine an occurrence temperature of a coloring reaction of
the component (a) and the component (b) is encapsulated in a
microcapsule comprising an organic resin,
10 an N-vinyl-2-pyrrolidone polymer having a degree of
polymerization of 2 to 20,
glycerin, and
water, and in this reversibly thermochromic aqueous ink
composition,
15 when contents (% by mass) of the reversibly
thermochromic microcapsule pigment, the N-vinyl-2-pyrrolidone polymer, and the glycerin with respect to a total mass of the ink composition are PMC, PPVP, and PG, respectively,
0.3 ≤ PMC/(PPVP + PG) ≤ 4, and
20 0.2 ≤ PPVP/PG ≤ 5.
[0007]
A refill according to the present invention is characterized
by incorporating the reversibly thermochromic ink composition.
[0008]
25 An aqueous ballpoint pen according to the present
invention is characterized by incorporating the reversibly thermochromic ink composition.
Advantageous Effects of Invention
30 [0009]
According to the present invention, there is provided a
reversibly thermochromic ink composition having writability, in
particular, less blurring at the start of writing even when a pen
tip is dried. In addition, this ink composition is also excellent in
35 an effect of suppressing aggregation of organic colorant particles,
an increase in viscosity of the composition, a decrease in
4

handwriting density, and the like.
Brief Description of Drawings
[0010]
5 FIG. 1 is a graph for explaining a hysteresis characteristic
of a thermochromic color-memory composition in a color density-temperature curve.
FIG. 2 is a graph for explaining the hysteresis
characteristic of another thermochromic color-memory
10 composition in the color density-temperature curve.
FIG. 3 is a cross-sectional view showing an example of a ballpoint pen of a first embodiment of the present invention.
FIG. 4 is a cross-sectional view showing an example of a
ballpoint pen of a second embodiment of the present invention.
15 FIG. 5 is a cross-sectional view showing an example of a
ballpoint pen refill of the present invention.
FIG. 6 is a cross-sectional view showing an example of a
pen tip (ballpoint pen tip) provided in the ballpoint pen and the
ballpoint pen refill of the present invention.
20 FIG. 7 is a cross-sectional view taken along line X-X of FIG.
6.
FIG. 8 is a handwriting after evaluation of dry-up resistance when an ink composition of Example is used.
FIG. 9 is the handwriting after evaluation of the dry-up
25 resistance when the ink composition of Comparative Example is
used.
Description of Embodiments
[0011]
30 An embodiment of the present invention will be described
in detail below.
[0012]
<>
35 An aqueous ink composition for reversibly thermochromic
writing instrument (hereinafter, may be simply referred to as an
5

“ink composition”) according to the present invention contains a
reversibly thermochromic microcapsule pigment, a polymer of N-
vinyl-2-pyrrolidone, glycerin, and water. Each of these
components will be described in detail below.
5 [0013]

In the present invention, a reversibly thermochromic
microcapsule pigment (hereinafter, may be simply referred to as
“microcapsule pigment”) includes
10 (a) an electron-donating color-developing organic
compound,
(b) an electron-accepting compound, and
(c) a reaction medium which reversibly induces an electron
transfer reaction between the component (a) and the component
15 (b) in a specific temperature range.
[0014]
As the microcapsule pigment, it is possible to use a
microcapsule pigment described in JP S51-44706 B, JP S51-
44707 B, JP H1-29398 B, etc. These microcapsule pigments
20 change color above and below a predetermined temperature
(color changing point), exhibit a decolored state in a temperature
range not lower than an upper color changing point, and exhibit
a colored state in a temperature range not higher than a lower
color changing point. The microcapsule pigments have
25 characteristics in which only one specific state, of the both states,
exists in an ordinary temperature region, and the other state is maintained while heat or cold required for the other state to be expressed is being applied, but the state in the ordinary temperature region is restored once the application of heat or
30 cold is terminated. Here, the composition contained in these
microcapsule pigments is a reversibly thermochromic
composition of heat-decoloring type (decolored when heated, and
colored when cooled) having characteristics in which a
temperature range representing a degree of hysteresis
35 (hereinafter referred to as a hysteresis width ΔH) is relatively
small (ΔH = 1 to 7°C) (see FIG. 1).
6

[0015]
Also, it is possible to use a microcapsule pigment described
in JP H4-17154 B, JP H7-179777 A, JP H7-33997 A, JP H8-39936
A, etc. These microcapsule pigments exhibit a relatively large
5 hysteresis characteristic (ΔH = 8 to 50°C). That is, the color
changes along very different paths in the curve of plots showing color development density change with temperature change between when the temperature increases from a region lower than the discoloration range and when the temperature decreases
10 from a region higher than the discoloration range (see FIG. 2).
[0016]
The hysteresis characteristics of the reversibly
thermochromic composition in a color density-temperature curve will be described in detail below with reference to the drawings.
15 [0017]
In FIG. 2, the color density is plotted on the ordinate and the temperature is plotted on the abscissa. A change in the color density due to temperature change proceeds along the arrow. Here, A is a point showing the density at a temperature t4 at
20 which a completely decolored state is achieved (hereinafter
referred to as complete decoloring temperature); B is a point showing the density at a temperature t3 at which decoloring starts (hereinafter referred to as decoloring starting temperature); C is a point showing the density at a temperature t2 at which coloring
25 starts (hereinafter referred to as coloring starting temperature);
and D is a point showing the density at a temperature t1 at which a completely colored state is achieved (hereinafter referred to as complete coloring temperature). [0018]
30 The discoloration temperature range is a temperature
range between t1 and t4 where a colored state or a decolored state can be provided, and a temperature range between t2 and t3 where difference in color density is large is an essentially two-phase retaining temperature range.
35 [0019]
A length of a line segment EF is a measure showing
7

contrast of discoloration, and a length of a line segment HG
passing through a midpoint of the line segment EF is the
hysteresis width ΔH. When this ΔH value is small, only specified
state of both states before and after discoloration can exist in the
5 ordinary temperature region. When the ΔH value is large, it is
easy to keep each state before and after discoloration. [0020]
As the reversibly thermochromic composition having a color-memory property, specifically, it can be effectively
10 functioned for the retention of color shown at an ordinary state
(daily life temperature region) by specifying the complete coloring temperature t1 to a temperature obtained only in a freezer, a cold district, and the like, i.e., a range of -50 to 0°C, preferably -40 to -5°C, more preferably -30 to -10°C and the
15 complete decoloring temperature t4 to a temperature obtained
from frictional heat generated with a frictional body or a familiar heating body such as a hair dryer, i.e., a range of 45 to 95°C, preferably 50 to 90°C, more preferably 60 to 80°C and specifying the ΔH value to 40 to 100°C.
20 [0021]
Specific compounds to be used as the respective components (a), (b), and (c) will be exemplified below. [0022]
The component (a) of the present invention, namely, an
25 electron-donating color-developing organic compound, is a color-
determining component which develops a color by donating an electron(s) to the component (b), which is a color developer. [0023]
Examples of the electron-donating color-developing
30 organic compound include phthalide compounds, fluoran
compounds, styrynoquinoline compounds, diazarhodamine
lactone compounds, pyridine compounds, quinazoline compounds,
and bisquinazoline compounds, among which phthalide
compounds and fluoran compounds are preferred.
35 [0024]
Examples of the phthalide compounds include
8

diphenylmethane phthalide compounds, phenylindolyl phthalide
compounds, indolyl phthalide compounds, diphenylmethane
azaphthalide compounds, phenylindolyl azaphthalide compounds,
and derivatives of these compounds, among which phenylindolyl
5 azaphthalide compounds and their derivatives are preferred.
Examples of the fluoran compounds include aminofluoran
compounds, alkoxyfluoran compounds, and derivatives of these
compounds.
[0025]
10 Hereinafter, compounds that can be used for the
component (a) are exemplified. 3,3-bis(p-dimethylaminophenyl)-6-dimethylaminophthalide,
3-(4-diethylaminophenyl)-3-(1-ethyl-2-methylindol-3-
yl)phthalide,
15 3,3-bis(1-n-butyl-2-methylindol-3-yl)phthalide,
3,3-bis(2-ethoxy-4-diethylaminophenyl)-4-azaphthalide, 3-(2-ethoxy-4-diethylaminophenyl)-3-(1-ethyl-2-methylindol-3-yl)-4-azaphthalide,
3-(2-hexyloxy-4-diethylaminophenyl)-3-(1-ethyl-2-
20 methylindol-3-yl)-4-azaphthalide,
3-[2-ethoxy-4-(N-ethylanilino)phenyl]-3-(1-ethyl-2-methylindol-3-yl)-4-azaphthalide,
3-(2-acetamido-4-diethylaminophenyl)-3-(1-propylindol-
3-yl)-4-azaphthalide,
25 3,6-bis(diphenylamino)fluoran,
3,6-dimethoxyfluoran, 3,6-di-n-butoxyfluoran,
2-methyl-6-(N-ethyl-N-p-tolylamino)fluoran,
3-chloro-6-cyclohexylaminofluoran,
30 2-methyl-6-cyclohexylaminofluoran,
2-(2-chloroamino)-6-dibutylaminofluoran,
2-(2-chloroanilino)-6-di-n-butylaminofluoran,
2-(3-trifluoromethylanilino)-6-diethylaminofluoran,
2-(3-trifluoromethylanilino)-6-dipentylaminofluoran,
35 2-dibenzylamino-6-diethylaminofluoran,
2-N-methylanilino-6-(N-ethyl-N-p-tolylamino)fluoran,
9

1,3-dimethyl-6-diethylaminofluoran,
2-chloro-3-methyl-6-diethylaminofluoran,
2-anilino-3-methyl-6-diethylaminofluoran,
2-anilino-3-methoxy-6-diethylaminofluoran,
5 2-anilino-3-methyl-6-di-n-butylaminofluoran,
2-anilino-3-methoxy-6-di-n-butylaminofluoran, 2-xylidino-3-methyl-6-diethylaminofluoran,
2-anilino-3-methyl-6-(N-ethyl-N-p-tolylamino)fluoran,
1,2-benz-6-diethylaminofluoran,
10 1,2-benz-6-(N-ethyl-N-isobutylamino)fluoran,
1,2-benz-6-(N-ethyl-N-isoamylamino)fluoran,
2-(3-methoxy-4-dodecoxystyryl)quinoline,
spiro[5H-[1]benzopyrano[2,3-d]pyrimidine-
5,1'(3'H)isobenzofuran]-3'-one,
15 2-diethylamino-8-diethylamino-4-methyl,
spiro[5H-[1]benzopyrano[2,3-d]pyrimidine-5,1'(3'H)isobenzofuran]-3'-one,
2-di-n-butylamino-8-di-n-butylamino-4-methyl,
spiro[5H-[1]benzopyrano[2,3-d]pyrimidine-
20 5,1'(3'H)isobenzofuran]-3'-one,
2-di-n-butylamino-8-diethylamino-4-methyl, spiro[5H-[1]benzopyrano[2,3-d]pyrimidine-5,1'(3'H)isobenzofuran]-3'-one,
2-di-n-butylamino-8-(N-ethyl-N-i-amylamino)-4-methyl,
25 spiro[5H-[1]benzopyrano[2,3-d]pyrimidine-
5,1'(3'H)isobenzofuran]-3'-one,
2-dibutylamino-8-dipentylamino-4-methyl,
4,5,6,7-tetrachloro-3-(4-dimethylamino-2-
methoxyphenyl)-3-(1-butyl-2-methyl-1H-indol-3-yl)-1(3H)-
30 isobenzofuranone,
4,5,6,7-tetrachloro-3-(4-diethylamino-2-ethoxyphenyl)-3-(1-ethyl-2-methyl-1H-indol-3-yl)-1(3H)-isobenzofuranone,
4,5,6,7-tetrachloro-3-(4-diethylamino-2-ethoxyphenyl)-
3-(1-pentyl-2-methyl-1H-indol-3-yl)-1(3H)-isobenzofuranone,
35 4,5,6,7-tetrachloro-3-(4-diethylamino-2-methylphenyl)-
3-(1-ethyl-2-methyl-1H-indol-3-yl)-1(3H)-isobenzofuranone,
10

3',6'-bis[phenyl(2-methylphenyl)amino]-spiro[isobenzofuran-1(3H),9'-[9H]xanthen]-3-one,
3',6'-bis[phenyl(3-methylphenyl)amino]-
spiro[isobenzofuran-1(3H),9'-[9H]xanthene]-3-one,
5 3',6'-bis[phenyl(3-ethylphenyl)amino]-
spiro[isobenzofuran-1(3H),9'-[9H]xanthene]-3-one,
2,6-bis(2'-ethyloxyphenyl)-4-(4'-dimethylaminophenyl)pyridine,
2,6-bis(2',4'-diethyloxyphenyl)-4-(4'-
10 dimethylaminophenyl)pyridine,
2-(4'-dimethylaminophenyl)-4-methoxyquinazoline, and
4,4'-ethylenedioxy-bis[2-(4-
diethylaminophenyl)quinazoline]
[0026]
15 The fluorans may be compounds which contain a
substituent in a xanthene ring-forming phenyl group, and in
addition, may also be compounds which have a blue or black color
and which contain a substituent in a xanthene ring-forming
phenyl group as well as in a lactone ring-forming phenyl group
20 (these substituents may be, for example, an alkyl group such as
a methyl group or a halogen atom such as a chloro group). [0027]
The component (b), namely an electron-accepting
compound, is a compound which receives an electron(s) from the
25 component (a) and functions as a color developer of the
component (a). [0028]
Examples of the electron-accepting compound include
active proton-containing compounds; pseudo-acidic compounds
30 (compounds which are not acids but each act as an acid in a
composition to cause the component (a) to develop a color); and
compounds with electron vacancies. Among these, the
component (b) is preferably a compound selected from active
proton-containing compounds.
35 [0029]
Examples of the compounds having active protons include
11

phenolic hydroxy group-containing compounds and derivatives
thereof, carboxylic acids and derivatives thereof, preferably
aromatic carboxylic acids and derivatives thereof, aliphatic
carboxylic acids having 2 to 5 carbon atoms and derivatives
5 thereof, 2-hydroxycarboxylic acid derivatives, N-substituted
amino acid derivatives, acidic phosphoric acid esters and
derivatives thereof, acidic phosphoric esters and derivatives
thereof, azole-based compounds and derivatives thereof, 1,2,3-
triazole and derivatives thereof, cyclic carbosulfoimides,
10 halohydrins having 2 to 5 carbon atoms, sulfonic acids and
derivatives thereof, and inorganic acids.
[0030]
Examples of the pseudo-acidic compounds include metal
salts of the phenolic hydroxy group-containing compounds, metal
15 salts of the carboxylic acids, metal salts of the acidic phosphoric
esters, metal salts of the sulfonic acids, aromatic carboxylic
anhydrides, aliphatic carboxylic anhydrides, anhydrides of mixed
acids of aromatic carboxylic acids and sulfonic acids, cycloolefin
dicarboxylic anhydrides, urea and derivatives thereof, thiourea
20 and derivatives thereof, guanidine and derivatives thereof, and
halogenated alcohols. [0031]
Examples of the compounds having electron holes include
borates, borate esters, and inorganic salts.
25 [0032]
Among these compounds, the phenolic hydroxy group-
containing compound is preferable because effective
thermochromic properties can be developed.
[0033]
30 The phenolic hydroxy group-containing compounds include
a wide range of compounds, ranging from monophenol
compounds to polyphenol compounds, and bis-type tris-type
phenols, phenol-aldehyde condensation resins and the like are
also included therein. Among the phenolic hydroxy group-
35 containing compounds, those which contain at least two benzene
rings are preferred. Further, these compounds may also have a
12

substituent, examples of which include an alkyl group, an aryl
group, an acyl group, an alkoxycarbonyl group, a carboxy group
and an ester thereof, as well as an amide group and a halogen
group.
5 [0034]
Examples of the metal contained in the metal salts of the
phenolic hydroxy group-containing compound and the like include
sodium, potassium, calcium, zinc, zirconium, aluminum,
magnesium, nickel, cobalt, tin, copper, iron, vanadium, titanium,
10 lead, and molybdenum.
[0035]
Examples of the compound having one phenolic hydroxy
group include
phenol,
15 o-cresol,
m-cresol,
p-cresol,
4-ethylphenol,
4-n-propylphenol,
20 4-n-butylphenol,
2-tert-butylphenol,
3-tert-butylphenol,
4-tert-butylphenol,
4-n-pentylphenol,
25 4-tert-pentylphenol,
4-n-octylphenol,
4-tert-octylphenol,
4-n-nonylphenol,
4-n-dodecylphenol,
30 3-n-pentadecylphenol,
4-n-stearylphenol,
1-(4-hydroxyphenyl)decane-1-one,
4-chlorophenol,
4-bromophenol,
35 4-trifluoromethylphenol,
4-methylthiophenol,
13

4-nitrophenol,
2-phenylphenol,
4-phenylphenol,
2-benzylphenol,
5 2-benzyl-4-chlorophenol,
4-cumylphenol,
4-hydroxybenzophenone,
4,4'-dihydroxybenzophenone,
4-chloro-4'-hydroxybenzophenone,
10 4-fluoro-4'-hydroxybenzophenone,
4-cyclohexylphenol,
2-hydroxybenzyl alcohol,
3-hydroxybenzyl alcohol,
4-hydroxybenzyl alcohol,
15 4-(2-hydroxyethyl)phenol,
3-methoxyphenol,
4-ethoxyphenol,
4-n-propoxyphenol,
4-n-butoxyphenol,
20 4-n-heptyloxyphenol,
4-(2-methoxyethyl)phenol,
α-naphthol,
β-naphthol,
2,3-dimethylphenol,
25 2,4-dimethylphenol,
2,6-dimethylphenol,
2,6-di-tert-butylphenol,
2,4-dichlorophenol,
2,4-difluorophenol,
30 thymol,
3-methyl-4-methylthiophenol,
2-tert-butyl-5-methylphenol,
2,6-bis(hydroxymethyl)-4-methylphenol,
2,3,5-trimethylphenol,
35 2,6-bis(hydroxymethyl)-4-tert-octylphenol,
6-hydroxy-1,3-benzooxathiol-2-one,
14

2,4-bis(phenylsulfonyl)phenol,
2,4-bis(phenylsulfonyl)-5-methylphenol,
2,4-bis(4-methylphenylsulfonyl)phenol,
2-phenylphenol, 4-phenylphenol,
5 2,6-diphenylphenol,
3-benzylbiphenyl-2-ol,
3,5-dibenzylbiphenyl-4-ol,
4-cyano-4'-hydroxybiphenyl,
1-hydroxybenzotriazole,
10 1-hydroxy-5-methylbenzotriazole,
1-hydroxy-5-chlorobenzotriazole,
1-hydroxy-5-methoxybenzotriazole,
1-hydroxy-4-benzoylaminobenzotriazole,
1-hydroxy-4,5,6,7-tetrachlorobenzotriazole,
15 1,4-hydroxybenzotriazole,
1-hydroxy-5-nitrobenzotriazole,
1-hydroxy-5-phenylbenzotriazole,
1-hydroxy-5-benzylbenzotriazole,
1-hydroxy-5-ethylbenzotriazole,
20 1-hydroxy-5-n-octylbenzotriazole,
1-hydroxy-5-n-butylbenzotriazole,
n-butyl 4-hydroxybenzoate,
n-octyl 4-hydroxybenzoate,
4-hydroxybenzoate 2-heptadecafluorooctylethane,
25 benzyl 4-hydroxybenzoate,
4-hydroxybenzoate-o-methylbenzyl,
4-hydroxybenzoate-m-methylbenzyl,
4-hydroxybenzoate-p-methylbenzyl,
4-hydroxybenzoate-p-ethylbenzyl,
30 4-hydroxybenzoate-p-propylbenzyl,
4-hydroxybenzoate-p-tert-butylbenzyl,
phenylethyl 4-hydroxybenzoate,
4-hydroxybenzoate-o-methylphenylethyl,
4-hydroxybenzoate-m-methylphenylethyl,
35 4-hydroxybenzoate-p-methylphenylethyl,
4-hydroxybenzoate-p-ethylphenylethyl,
15

4-hydroxybenzoate-p-propylphenylethyl, and
4-hydroxybenzoate-p-tert-butylphenylethyl. [0036]
Examples of the compound having two phenolic hydroxy
5 groups include
resorcin,
2-methylresorcin,
4-n-hexylresorcin,
4-n-octylresorcin,
10 4-tert-octylresorcin,
4-benzoylresorcin,
4-nitroresorcin,
methyl β-resorcinol,
benzyl β-resorcinol,
15 2-chloro-4-pentanoylresorcin,
6-chloro-4-pentanoylresorcin,
2-chloro-4-hexanoyl resorcin,
6-chloro-4-hexanoylresorcin,
2-chloro-4-propanoylresorcin,
20 6-chloro-4-propanoylresorcin,
2,6-dichloro-4-propanoylresorcin,
6-fluoro-4-propanoylresorcin,
2-chloro-4-phenylacetylresorcin,
4-phenylacetyl-6-chlororesorcin,
25 2-chloro-4-β-phenylpropanoylresorcin,
6-chloro-4-β-phenylpropanoylresorcin,
2-chloro-4-phenoxyacetylresorcin,
6-chloro-4-phenoxyacetylresorcin,
4-benzoyl-2-chlororesorcin,
30 6-chloro-4-m-methylbenzoylresorcin,
4-[1',3',4',9'a-tetrahydro-6'-hydroxyspiro(cyclohexane-1,9'-[9H]-xanthene)-4'a-[2H]-yl]-1,3-benzenediol,
hydroquinone,
methyl hydroquinone,
35 trimethyl hydroquinone,
catechol,
16

4-tert-butylcatechol,
1,6-dihydroxynaphthalene,
2,7-dihydroxynaphthalene,
1,5-dihydroxynaphthalene,
5 2,6-dihydroxynaphthalene,
2,4-dihydroxybenzophenone,
2,4-dihydroxy-2'-methylbenzophenone, 2,4-dihydroxy-3'-methylbenzophenone, 2,4-dihydroxy-4'-methylbenzophenone,
10 2,4-dihydroxy-4'-ethylbenzophenone,
2,4-dihydroxy-4'-n-propylbenzophenone, 2,4-dihydroxy-4'-isopropylbenzophenone, 2,4-dihydroxy-4'-n-butylbenzophenone, 2,4-dihydroxy-4'-isobutylbenzophenone,
15 2,4-dihydroxy-4'-tert-butylbenzophenone,
2,4-dihydroxy-4'-n-pentylbenzophenone, 2,4-dihydroxy-4'-n-hexylbenzophenone, 2,4-dihydroxy-4'-n-heptylbenzophenone, 2,4-dihydroxy-4'-n-octylbenzophenone,
20 2,4-dihydroxy-4'-n-decylbenzophenone,
2,4-dihydroxy-2',3'-dimethylbenzophenone, 2,4-dihydroxy-2',4'-dimethylbenzophenone, 2,4-dihydroxy-2',5'-dimethylbenzophenone, 2,4-dihydroxy-2',6'-dimethylbenzophenone,
25 2,4-dihydroxy-3',4'-dimethylbenzophenone,
2,4-dihydroxy-3',5'-dimethylbenzophenone, 2,4-dihydroxy-2',4',6'-trimethylbenzophenone, 2,4-dihydroxy-2'-methoxybenzophenone, 2,4-dihydroxy-3'-methoxybenzophenone,
30 2,4-dihydroxy-4'-methoxybenzophenone,
2,4-dihydroxy-2'-ethoxybenzophenone, 2,4-dihydroxy-4'-ethoxybenzophenone, 2,4-dihydroxy-4'-n-propoxybenzophenone, 2,4-dihydroxy-4'-isopropoxybenzophenone,
35 2,4-dihydroxy-4'-n-butoxybenzophenone,
2,4-dihydroxy-4'-isobutoxybenzophenone,
17

2,4-dihydroxy-4'-n-pentyloxybenzophenone,
2,4-dihydroxy-4'-n-hexyloxybenzophenone,
2,4-dihydroxy-4'-n-heptyloxybenzophenone,
2,4-dihydroxy-4'-n-octyloxybenzophenone,
5 2,4-dihydroxy-4'-n-nonyloxybenzophenone,
2,4-dihydroxy-2',3'-dimethoxybenzophenone, 2,4-dihydroxy-2',4'-dimethoxybenzophenone, 2,4-dihydroxy-2',5'-dimethoxybenzophenone, 2,4-dihydroxy-2',6'-dimethoxybenzophenone,
10 2,4-dihydroxy-3',4'-dimethoxybenzophenone,
2,4-dihydroxy-3',5'-dimethoxybenzophenone, 2,4-dihydroxy-3',4'-diethoxybenzophenone, 2,4-dihydroxy-2',3',4'-trimethoxybenzophenone, 2,4-dihydroxy-2',3',6'-trimethoxybenzophenone,
15 2,4-dihydroxy-3',4',5'-trimethoxybenzophenone, and
2,4-dihydroxy-3',4',5'-triethoxybenzophenone. [0037]
In addition, examples of a bis-type phenol compound include
20 1,1-bis(4-hydroxyphenyl)ethane,
1,1-bis(4-hydroxyphenyl)propane, 1,1-bis(4-hydroxyphenyl)n-butane, 1,1-bis(4-hydroxyphenyl)n-pentane, 1,1-bis(4-hydroxyphenyl)n-hexane,
25 1,1-bis(4-hydroxyphenyl)n-heptane,
1,1-bis(4-hydroxyphenyl)n-octane, 1,1-bis(4-hydroxyphenyl)n-nonane, 1,1-bis(4-hydroxyphenyl)n-decane, 1,1-bis(4-hydroxy-3-methylphenyl)decane,
30 1,1-bis(4-hydroxyphenyl)n-dodecane,
1,1-bis(4-hydroxyphenyl)-2-methylpropane, 1,1-bis(4-hydroxyphenyl)-3-methylbutane, 1,1-bis(4-hydroxyphenyl)-3-methylpentane, 1,1-bis(4-hydroxyphenyl)-2,3-dimethylpentane,
35 1,1-bis(4-hydroxyphenyl)-2-ethylbutane,
1,1-bis(4-hydroxyphenyl)-2-ethylhexane,
18

1,1-bis(4-hydroxyphenyl)-3,7-dimethyloctane, 1,1-bis(4-hydroxyphenyl)cyclohexane,
1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane,
1,1-bis(4-hydroxy-3-methyl)cyclohexane,
5 diphenolic acid,
1-phenyl-1,1-bis(4-hydroxyphenyl)methane, 2,2-bis(4-hydroxyphenyl)propane, 2,2-bis(4-hydroxyphenyl)n-butane, 2,2-bis(4-hydroxyphenyl)n-pentane,
10 2,2-bis(4-hydroxyphenyl)n-hexane,
2,2-bis(4-hydroxyphenyl)n-heptane, 2,2-bis(4-hydroxyphenyl)n-octane, 2,2-bis(4-hydroxyphenyl)n-nonane, 2,2-bis(4-hydroxyphenyl)n-decane,
15 2,2-bis(4-hydroxyphenyl)n-dodecane,
2,2-bis(4-hydroxyphenyl)-6,10,14-trimethylpentadecane, 1-phenyl-1,1-bis(4-hydroxyphenyl)ethane, 2,2-bis(4-hydroxyphenyl)methylpropionate, 2,2-bis(4-hydroxyphenyl)butyl propionate,
20 2,2-bis(4-hydroxy-3-methylphenyl)methylpropionate,
2,2-bis(4-hydroxyphenyl)ethylpropionate, 2,2-bis(4-hydroxyphenyl)-4-methylpentane, 2,2-bis(4-hydroxyphenyl)-4-methylhexane, 2,2-bis(4-hydroxyphenyl)hexafluoropropane,
25 2,2-bis(3,5-dihydroxymethyl-4-
hydroxyphenyl)hexafluoropropane,
2,2-bis(4-hydroxy-3-methylphenyl)propane,
2,2-bis(4-hydroxy-3-methylphenyl)butane,
2,2-bis(4-hydroxy-3-isopropylphenyl)propane,
30 2,2-bis(3-sec-butylphenyl-4-hydroxy)propane,
2,2-bis(4-hydroxy-3-phenylphenyl)propane, 2,2-bis(3-tert-butyl-4-hydroxyphenyl)propane, 2,2-bis(3-fluoro-4-hydroxyphenyl)propane, 2,2-bis(3,5-dihydroxymethyl-4-hydroxyphenyl)propane,
35 9,9-bis(4-hydroxy-3-methylphenyl)fluorene,
1,3-bis[2-(4-hydroxyphenyl)-2-propyl]benzene,
19

1,4-bis[2-(4-hydroxyphenyl)-2-propyl]benzene,
3,3-bis(4-hydroxyphenyl)oxindole,
3,3-bis(4-hydroxy-3-methylphenyl)oxindole,
bis(2-hydroxyphenyl)methane,
5 bis(2-hydroxy-5-methylphenyl)methane,
bis(2-hydroxy-3-hydroxymethyl-5-methyl)methane, 4,4'-[1,4-phenylene bis(1-methylethylidene)]bis(2-methylphenol),
1,1-bis(4-hydroxy-3-phenylphenyl)cyclohexane,
10 3,3-ethyleneoxydiphenol,
1,4-bis(4-hydroxybenzoart)-3-methylbenzene, 4,4"-dihydroxy-3"-methyl-p-terphenyl, 4,4"-dihydroxy-3"-isopropyl-p-terphenyl, 2,2-dimethyl-1,3-bis(4-hydroxybenzoyloxy)propane,
15 2,2'-biphenol,
4,4'"-dihydroxy-p-quaterphenyl, 4,4-dihydroxydiphenyl ether, bis(4-hydroxyphenylthioethyl)ether
bis(4-hydroxyphenyl)sulfone,
20 4-benzyloxy-4'-hydroxydiphenylsulfone,
4-(4-methylbenzyloxy)-4'-hydroxydiphenylsulfone, 4-(4-ethylbenzyloxy)-4'-hydroxydiphenylsulfone, 4-(4-n-propylbenzyloxy)-4'-hydroxydiphenylsulfone, 4-(4-isopropylbenzyloxy)-4'-hydroxydiphenylsulfone,
25 4-(4-n-butylbenzyloxy)-4'-hydroxydiphenylsulfone,
4-(4-isobutylbenzyloxy)-4'-hydroxydiphenylsulfone, 4-(4-sec-butylbenzyloxy)-4'-hydroxydiphenylsulfone, 4-(4-tert-butylbenzyloxy)-4'-hydroxydiphenylsulfone, 4-(3-methylbenzyloxy)-4'-hydroxydiphenylsulfone,
30 4-(3-ethylbenzyloxy)-4'-hydroxydiphenylsulfone,
4-(3-n-propylbenzyloxy)-4'-hydroxydiphenylsulfone, 4-(3-isopropylbenzyloxy)-4'-dihydroxyphenyl sulfone, 4-(3-n-butylbenzyloxy)-4'-hydroxydiphenylsulfone, 4-(3-isobutylbenzyloxy)-4'-hydroxydiphenylsulfone,
35 4-(3-sec-butylbenzyloxy)-4'-hydroxydiphenylsulfone,
4-(3-tert-butylbenzyloxy)-4'-hydroxydiphenylsulfone,
20

4-(2-methylbenzyloxy)-4'-hydroxydiphenylsulfone,
4-(2-ethylbenzyloxy)-4'-hydroxydiphenylsulfone,
4-(2-n-propylbenzyloxy)-4'-hydroxydiphenylsulfone,
4-(2-isopropylbenzyloxy)-4'-hydroxydiphenylsulfone,
5 4-(2-n-butylbenzyloxy)-4'-hydroxydiphenylsulfone,
4-(2-isobutylbenzyloxy)-4'-hydroxydiphenylsulfone, 4-(2-sec-butylbenzyloxy)-4'-hydroxydiphenylsulfone, 4-(2-tert-butylbenzyloxy)-4'-hydroxydiphenylsulfone, 2,4'-dihydroxydiphenylsulfone,
10 3,4'-dihydroxydiphenyl sulfone,
4-hydroxydiphenyl sulfone, 4-methyl-4'-hydroxidiphenyl sulfone, 4-ethyl-4'-hydroxydiphenyl sulfone, 4-n-propyl-4'-hydroxydiphenyl sulfone,
15 4-isopropyl-4'-hydroxydiphenyl sulfone,
4-chloro-4'-hydroxydiphenyl sulfone, 4-fluoro-4'-hydroxydiphenyl sulfone,
4-chloro-2-methyl-4'-hydroxydiphenyl sulfone, 4-methoxy-4'-hydroxydiphenyl sulfone,
20 4-ethoxy-4'-hydroxydiphenyl sulfone,
4-n-propoxy-4'-hydroxydiphenyl sulfone, 4-isopropoxy-4'-hydroxydiphenyl sulfone, 4-n-butyloxy-4'-hydroxydiphenyl sulfone, 4-isobutoxy-4'-hydroxydiphenyl sulfone,
25 4-sec-butoxy-4'-hydroxydiphenyl sulfone,
4-tert-butoxy-4'-hydroxydiphenyl sulfone, 4-n-pentyloxy-4'-hydroxydiphenylsulfone, 4-isopentyloxy-4'-hydroxydiphenyl sulfone, 4-(1-propenyloxy)-4'-hydroxydiphenyl sulfone,
30 4-(2-propenyloxy)-4'-hydroxydiphenyl sulfone,
4-benzyloxy-4'-hydroxydiphenyl sulfone, 4-(β-phenoxyethoxy)-4'-hydroxydiphenyl sulfone, 4-(β-phenoxypropoxyl)-4'-hydroxydiphenyl sulfone, bis(2-allyl-4-hydroxydiphenyl)sulfone,
35 bis[4-hydroxy-3-(2-propenyl)phenyl]sulfone,
bis(3,5-dibromo-4-hydroxyphenyl)sulfone,
21

bis(3,5-dichloro-4-hydroxyphenyl)sulfone,
bis(3-phenyl-4-hydroxyphenyl)sulfone,
bis(4-hydroxy-3-n-propylphenyl)sulfone,
bis(4-hydroxy-3-methylphenyl)sulfone,
5 3,4-dihydroxydiphenyl sulfone,
3',4'-dihydroxy-4-methyldiphenylsulfone,
3,4,4'-trihydroxydiphenyl sulfone,
bis(3,4-dihydroxyphenyl)sulfone,
2,3,4-trihydroxydiphenyl sulfone,
10 4-isopropoxy-4'-hydroxydiphenyl sulfone,
4-n-propoxy-4'-hydroxydiphenyl sulfone,
4-allyloxy-4'-hydroxydiphenyl sulfone,
4-benzyloxy-4'-hydroxydiphenyl sulfone,
4-(2-propenyloxy)-4'-hydroxydiphenyl sulfone,
15 3-benzyl-4-benzyloxy-4'-hydroxydiphenyl sulfone,
3-phenethyl-4-phenethyloxy-4'-hydroxydiphenyl sulfone,
3-methylbenzyl-4-methylbenzyloxy-4'-hydroxydiphenylsulfone,
4-benzyloxy-3'-benzyl-4'-hydroxydiphenylsulfone,
20 4-phenethyloxy-3'-phenethyl-4'-hydroxydiphenylsulfone,
4-methylbenzyloxy-3'-methylbenzyl-4'-hydroxydiphenylsulfone,
α,α'-bis{4-(p-hydroxyphenyl sulfone)phenoxy}-p-xylene,
4,4'-{oxybis(ethylene oxide-p-phenylene
25 sulfonyl)}diphenol
bis(4-hydroxyphenyl)sulfide,
bis(4-hydroxy-3-methylphenyl)sulfide,
bis(3,5-dimethyl-4-hydroxyphenyl)sulfide,
bis(3-ethyl-4-hydroxyphenyl)sulfide,
30 bis(3,5-diethyl-4-hydroxyphenyl)sulfide,
bis(4-hydroxy-3-n-propylphenyl)sulfide,
bis(3,5-di-n-propyl-4-hydroxyphenyl)sulfide,
bis(3-tert-butyl-4-hydroxyphenyl)sulfide,
bis(3,5-di-tert-butyl-4-hydroxyphenyl)sulfide,
35 bis(4-hydroxy-3-n-pentylphenyl)sulfide,
bis(3-n-hexyl-4-hydroxyphenyl)sulfide,
22

bis(3-n-heptyl-4-hydroxyphenyl)sulfide,
bis(5-tert-octyl-2-hydroxyphenyl)sulfide,
bis(2-hydroxy-3-tert-octylphenyl)sulfide,
bis(2-hydroxy-5-n-octyl-phenyl)sulfide,
5 bis(5-chloro-2-hydroxyphenyl)sulfide,
bis(3-cyclohexyl-4-hydroxyphenyl)sulfide,
bis(4-hydroxyphenylthioethoxy)methane,
1,5-(4-hydroxyphenylthio)-3-oxypentane, and
1,8-bis(4-hydroxyphenylthio)-3,6-dioxaoctane.
10 [0038]
Examples of the compound having three phenolic hydroxy groups include pyrogallol, phloroglucinol,
phloroglucinolcarboxylic acid, gallic acid, octyl gallate, and
dodecyl gallate.
15 [0039]
In addition, examples of a tris-type phenol compound include
4,4',4"-methylidine trisphenol,
4,4',4"-methylidine tris(2-methylphenol),
20 4,4'-[(2-hydroxyphenyl)methylene]bis(2,3,5-
trimethylphenol),
4,4'-[(4-hydroxyphenyl)methylene]bis(2-methylphenol),
4,4'-[(4-hydroxyphenyl)methylene]bis(2,6-
dimethylphenol),
25 4,4'-[(4-hydroxy-3-methoxyphenyl)methylene]bisphenol,
4,4'-[(4-hydroxyphenyl)methylene]bis(2-cyclohexyl-5-methylphenol),
4,4',4"-ethylidine trisphenol,
4,4',4"-ethyridinetris(2-methylphenol),
30 4,4'-[(2-hydroxyphenyl)methylene]bis(2-cyclohexyl-5-
methylphenol),
2,6-bis[(2-hydroxy-5-methylphenyl)methyl]-4-methylphenol,
2,4-bis[(2-hydroxy-5-methylphenyl)methyl]-6-
35 cyclohexylphenol,
4,4'-[1-{4-[1-(4-hydroxyphenyl)-1-23

methylethyl]phenyl}methylidene]bisphenol,
4,4'-[1-{4-[1-(4-hydroxyphenyl)-1-
methylethyl]phenyl}ethylidene]bisphenol,
4,4'-[1-{4-[1-(4-hydroxyphenyl)-1-
5 methylethyl]phenyl}propylidene]bisphenol,
4,4'-[1-{4-[1-(4-hydroxyphenyl)-1-
methylethyl]phenyl}butylidene]bisphenol,
4,4'-[1-{4-[1-(4-hydroxyphenyl)-1-
methylethyl]phenyl}pentylidene]bisphenol,
10 4,4'-[1-{4-[1-(4-hydroxyphenyl)-1-
methylethyl]phenyl}hexylidene]bisphenol, 4,4'-[1-{4-[1-(4-hydroxyphenyl)-1-methylethyl]phenyl}heptylidene]bisphenol, 4,4'-[1-{4-[1-(4-hydroxyphenyl)-1-15 methylethyl]phenyl}isobutylidene]bisphenol, 4,4'-[1-{4-[1-(4-hydroxyphenyl)-1-methylethyl]phenyl}neopentylidene]bisphenol,
2,2'-[1-{4-[1-(2-hydroxyphenyl)-1-
methylethyl]phenyl}ethylidene]bisphenol,
20 3,3'-[1-{4-[1-(3-hydroxyphenyl)-1-
methylethyl]phenyl}ethylidene]bisphenol,
4,4'-[1-{4-[1-(3-fluoro-4-hydroxyphenyl)-1-
methylethyl]phenyl}ethylidene]bis(2-fluorophenol),
4,4'-[1-{4-[1-(3-chloro-4-hydroxyphenyl)-1-
25 methylethyl]phenyl}ethylidene]bis(2-chlorophenol),
4,4'-[1-{4-[1-(3-bromo-4-hydroxyphenyl)-1-
methylethyl]phenyl}ethylidene]bis(2-bromophenol),
4,4'-[1-{4-[1-(4-hydroxy-3-methylphenyl)-1-
methylethyl]phenyl}ethylidene]bis(2-methylphenol),
30 4,4'-[1-{4-[1-(3-ethyl-4-hydroxyphenyl)-1-
methylethyl]phenyl}ethylidene]bis(2-ethylphenol),
4,4'-[1-{4-[1-(3-tert-butyl-4-hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bis(2-tert-butylphenol),
4,4'-[1-{4-[1-(4-hydroxy-3-trifluoromethylphenyl)-1-35 methylethyl]phenyl}etylidene]bis(2-trifluoromethylphenol), 1,1-bis(4-hydroxyphenyl)-4-(4-hydroxy-α-
24

ethyl)benzylcyclohexane,
4,4'-[(3-ethoxy-4-hydroxycyphenyl)methylene]bisphenol,
4,4'-[(3-hydroxyphenyl)methylene]bis(2,6-
dimethylphenol),
5 2,2'-[(4-hydroxyphenyl)methylene]bis(3,5-
dimethylphenol),
4,4'-[(4-hydroxy-3-methoxyphenyl)methylene]bis(2,6-dimethylphenol),
2,2'-[(2-hydroxyphenyl)methylene]bis(3,5,6-10 trimethylphenol),
4,4'-[(3-hydroxyphenyl)methylene]bis(2,3,6-trimethylphenol),
4,4'-[(4-hydroxyphenyl)methylene]bis(2,3,6-
trimethylphenol),
15 4,4'-[(3-hydroxyphenyl)methylene]bis(2-cyclohexyl-5-
methylphenol),
4,4'-[(4-hydroxyphenyl-3-methoxy)methylene]bis(2-cyclohexyl-5-methylphenol),
1,1-bis(4-hydroxyphenyl)-4-hydroxyphenylcyclohexane,
20 4,4'-[3-(5-cyclohexyl-4-hydroxy-2-methylphenyl)-3-
phenyl)propylidene]bis(2-cyclohexyl-5-methylphenol),
4,4'-[(2-hydroxyphenyl)methylene]bis(2-methylphenol),
2,4',4"-methylidine trisphenol,
4,4'-[(2-hydroxyphenyl)methylene]bis(3-methylphenol),
25 4,4'-[4-(4-hydroxyphenyl)-sec-butylidene]bis(4-
hydroxyphenol),
2,2'-[(3-hydroxyphenyl)methylene]bis(3,5-dimethylphenol),
4,4'-[(2-hydroxy-3-methoxyphenyl)methylene]bis(2,5-30 dimethylphenol),
4,4'-[(2-hydroxy-3-methoxyphenyl)methylene]bis(2,6-dimethylphenol),
2,2'-[(2-hydroxy-3-methoxyphenyl)methylene]bis(3,5-
dimethylphenol),
35 2,2'-[(3-hydroxy-4-methoxyphenyl)methylene]bis(3,5-
dimethylphenol),
25

2,2'-[(4-hydroxy-3-methoxyphenyl)methylene]bis(3,5-dimethylphenol),
4,4'-[(2-hydroxyphenyl)methylene]bis(2-
isopropylphenol),
5 4,4'-[(3-hydroxyphenyl)methylene]bis(2-
isopropylphenol),
4,4'-[(4-hydroxyphenyl)methylene]bis(2-isopropylphenol),
2,2'-[(3-hydroxyphenyl)methylene]bis(3,5,6-10 trimethylphenol),
2,2'-[(4-hydroxyphenyl)methylene]bis(3,5,6-trimethylphenol),
2,2'-[(4-3-ethoxy-4-hydroxyphenyl)methylene]bis(3,5-
dimethylphenol),
15 1,1-bis(4-hydroxy-3-methylphenyl)-4-(4-
hydroxyphenyl)cyclohexane,
4,4'-[(2-hydroxy-3-methoxyphenyl)methylene]bis(2-isopropylphenol),
4,4'-[(3-hydroxy-4-methoxyphenyl)methylene]bis(2-20 isopropylphenol),
4,4'-[(4-hydroxy-3-methoxyphenyl)methylene]bis(2-isopropylphenol),
2,2'-[(2-hydroxy-3-methoxyphenyl)methylene]bis(3,5,6-
trimethylphenol,
25 2,2'-[(3-hydroxy-4-methoxyphenyl)methylene]bis(3,5,6-
trimethylphenol),
2,2'-[(4-hydroxy-3-methoxyphenyl)methylene]bis(3,5,6-trimethylphenol),
4,4'-[(3-ethoxy-4-hydroxyphenyl)methylene]bis(2-30 isopropylphenol),
2,2'-[(3-ethoxy-4-hydroxyphenyl)methylene]bis(3,5,6-trimethylphenol),
4,4'-[(3-ethoxy-4-hydroxyphenyl)methylene]bis(2,3,6-
trimethylphenol),
35 1,1-bis(3,5-dimethyl-4-hydroxyphenyl)-4-(4-
hydroxyphenyl)cyclohexane,
26

4,4'-[(4-hydroxy-3-methoxyphenyl)methylene]bis(2-tert-butyl-5-methylphenol),
4,4'-[(2-hydroxyphenyl)methylene]bis(2-
cyclohexylphenol),
5 4,4'-[(3-hydroxyphenyl)methylene]bis(2-
cyclohexylphenol),
4,4'-[(3-ethoxy-4-hydroxyphenyl)methylene]bis(2-tert-butyl-6-methylphenol),
4,4'-[(3-methoxy-2-hydroxyphenyl)methylene]bis(2-10 cyclohexylphenol),
4,4'-[(3-hydroxy-4-methoxyphenyl)methylene]bis(2-cyclohexylphenol),
4,4'-[1-{4-[1-(3-fluoro-4-hydroxylophenyl)-1-
methylethyl]phenyl}ethylidene]bis(2-tert-butylphenol),
15 4,4'-[1-{4-[1-(3,5-dimethyl-4-hydroxyphenyl)-1-
methylethyl]phenyl}ethylidene]bis(2,6-dimethylphenol),
4,4'-[(3-ethoxy-4-hydroxyphenyl)methylene]bis(2-cyclohexyl-5-methylphenol),
4,4'-[(3-cyclohexyl-4-hydroxyphenyl)ethylidene]bis(2-20 cyclohexylphenol),
4,4'-[(5-cyclohexyl-4-hydroxy-2-methoxyphenyl)ethylidene]bis(2-cyclohexyl-5-methylphenol),
4,4'-[1-{4-[1-(3-cyclohexyl-4-hydroxyphenyl)-1-
methylethyl]phenyl}ethylidene]bis(2-cyclohexylphenol),
25 4,4'-[1-{4-[1-(3-fluoro-4-hydroxyphenyl)-1-
methylethyl]phenyl}ethylidene]bisphenol,
4,4'-[1-{4-[1-(3-fluoro-4-hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bis(2-methylphenol),
4,4'-[1-{4-[1-(3-fluoro-4-hydroxyphenyl)-1-30 methylethyl]phenyl}ethylidene]bis(2,6-dimethylphenol),
2,6-bis[(5-fluoro-2-hydroxyphenyl)methyl]-4-methylphenol,
2,6-bis[(3,5-dimethyl-4-hydroxyphenyl)methyl]-4-
methylphenol,
35 2,6-bis[(4-hydroxyphenyl)methyl]-4-methylphenol,
2,6-bis[(4-hydroxyphenyl)methyl]-4-ethylphenol,
27

2,4-bis[(4-hydroxy-3-methylphenyl)methyl]-6-methylphenol,
2,6-bis[(4-hydroxy-3-methylphenyl)methyl]-4-
methylphenol,
5 2,6-bis[(4-hydroxy-3-methylphenyl)methyl]-4-
ethylphenol,
2,6-bis[(2-hydroxy-5-methylphenyl)methyl]-4-ethylphenol,
2,6-bis[(3,5-dimethyl-2-hydroxyphenyl)methyl]-4-10 methylphenol,
2,6-bis[(2,4-dimethyl-6-hydroxyphenyl)methyl]-4-methylphenol,
2,4-bis[(4-hydroxyphenyl)methyl]-6-cyclohexylphenol,
2,6-bis[(2,5-dimethyl-4-hydroxyphenyl)methyl]-3,4-15 dimethylphenol,
2,6-bis[(2,5-dimethyl-4-hydroxyphenyl)methyl]-4-ethylphenol,
2,6-bis[(4-hydroxy-2,3,6-trimethylphenyl)methyl]-4-
methylphenol,
20 2,4-bis[(4-hydroxy-3-methylphenyl)methyl]-6-
cyclohexylphenol,
2,6-bis[(4-hydroxy-3-methylphenyl)methyl]-4-cyclohexylphenol,
2,6-bis[(2-hydroxy-5-methylphenyl)methyl]-4-25 cyclohexylphenol,
2,6-bis[(4-hydroxy-2,3,5-trimethylphenyl)methyl]-4-ethylphenol,
2,4-bis[(2,5-dimethyl-4-hydroxyphenyl)methyl]-6-
cyclohexylphenol,
30 4,4',4"-methylidine tris(2,6-dimethylphenol),
α-(4-hydroxy-3-methylphenyl)-α,α'-bis(4-hydroxyphenyl)-1-ethyl-4-isopropylbenzene,
-(4-hydroxy-3-methylphenyl)-α,α-bis(4-hydroxyphenyl)-
1-ethyl-4α'-isopropylbenzene,
35 α,α-bis(4-hydroxy-3-methylphenyl)-α'-(4-
hydroxyphenyl)-1-ethyl-4-isopropylbenzene,
28

α,α'-bis(4-hydroxy-3-methylphenyl)-α-(4-hydroxyphenyl)-1-ethyl-4-isopropylbenzene,
1,1-bis(4-hydroxyphenyl)-4-[1-(4-hydroxyphenyl)-1-
methylpropyl]cyclohexane,
5 2,6-bis[(3,5-dimethyl-4-hydroxyphenyl)methyl]-4-
ethylphenol,
1,1'-bis(4-hydroxyphenyl)-4-[1-(4-hydroxyphenyl)propyl]cyclohexane,
1,1'-bis(4-hydroxy-3-methylphenyl)-4-[1-(4-10 hydroxyphenyl)propyl]cyclohexane,
1,1'-bis(3,5-dimethyl-4-hydroxyphenyl)-4-[1-(4-hydroxyphenyl)propyl]cyclohexane,
1-(4-hydroxyphenyl)-1-[4,4-bis(4-
hydroxyphenyl)cyclohexyl]-4-isopropylcyclohexane,
15 4,4'-[3-(2,5-dimethyl-4-hydroxyphenyl)butylene]bis(2,5-
dimethylphenol),
1,3,5-tri(4-hydroxy-3-phenylphenyl)adamantane,
1,3,5-tri(3-cyclohexyl-4-hydroxyphenyl)adamantane,
2,4-bis[(3,5-dimethyl-4-hydroxyphenyl)methyl]-6-20 cyclohexylphenol,
2,6-bis[(2,5-dimethyl-4-hydroxyphenyl)methyl]-4-cyclohexylphenol,
2,4-bis[(3-cyclohexyl-4-hydroxyphenyl)methyl]-6-
methylphenol,
25 2,4-bis[(4-hydroxy-2,3,5-trimethylphenyl)methyl]-6-
cyclohexylphenol,
2,6-bis[(5-fluoro-2-hydroxyphenyl)methyl]-4-fluorophenol,
2,6-bis[(3-fluoro-4-hydroxyphenyl)methyl]-4-30 fluorophenol,
2,4-bis[(3-fluoro-4-hydroxyphenyl)methyl]-6-methylphenol,
4,4'-[3-(5-cyclohexyl-4-hydroxy-2-methylphenyl)-3-
biphenylpropylidene]bis(5-cyclohexyl-2-methylphenol),
35 4,4'-[3-(2,5-dimethyl-4-hydroxyphenyl)-3-
phenylpropylidene]bis(2,5-dimethylphenol),
29

2,4-bis[(2,5-dimethyl-4-hydroxyphenyl)methyl]-6-methylphenol,
1,1,2-tris(4-hydroxyphenyl)ethane,
1,1,3-tris(4-hydroxyphenyl)propane,
5 1,1,4-tris(4-hydroxyphenyl)butane,
1,2,2-tris(4-hydroxyphenyl)propane,
1,2,2-tris(4-hydroxyphenyl)butane,
1,2,2-tris(4-hydroxyphenyl)pentane,
1,2,2-tris(4-hydroxyphenyl)hexane,
10 1,2,2-tris(4-hydroxyphenyl)heptane,
1,2,2-tris(4-hydroxyphenyl)octane,
1,2,2-tris(4-hydroxyphenyl)-3-methylbutane 1,2,2-tris(4-hydroxyphenyl)-3,3-dimethylbutane,
1,2,2-tris(4-hydroxyphenyl)-4,4-dimethylpentane,
15 1,3,3-tris(4-hydroxyphenyl)butane,
1,3,3-tris(4-hydroxyphenyl)pentane,
1,3,3-tris(4-hydroxyphenyl)hexane,
1,3,3-tris(4-hydroxyphenyl)heptane,
1,3,3-tris(4-hydroxyphenyl)octane,
20 1,3,3-tris(4-hydroxyphenyl)nonane,
1,4,4-tris(4-hydroxyphenyl)pentane,
1,4,4-tris(4-hydroxyphenyl)hexane,
1,4,4-tris(4-hydroxyphenyl)heptane,
1,4,4-tris(4-hydroxyphenyl)octane,
25 1,4,4-tris(4-hydroxyphenyl)nonane,
1,4,4-tris(4-hydroxyphenyl)decane,
1,2,2-tis(2-hydroxyphenyl)propane,
1,1,2-tris(3-hydroxyphenyl)propane,
1-(4-hdroxyphenyl)-2,2-bis(2-hydroxyphenyl)propane,
30 1,2,2-tris(3-fluoro-4-hydroxyphenyl)propane,
1,2,2-tris(3-chloro-4-hydroxyphenyl)propane,
1,2,2-tris(3-bromo-4-hydroxyphenyl)propane,
2,2-bis(3-ethyl-4-hydroxyphenyl)-1-(4-
hydroxyphenyl)propane,
35 2,2-bis(3-tert-butyl-4-hydroxyphenyl)-1-(4-
hydroxyphenyl)propane,
30

2,2-bis(2-hydroxy-3-biphenylyl)-1-(4-hydroxyphenyl)propane,
2,2-bis(3-trifluoromethyl-4-hydroxyphenyl)-1-(4-
hydroxyphenyl)propane,
5 2-(3-methyl-4-hydroxyphenyl)-1,2-bis(4-
hydroxyphenyl)propane,
1-(3-methyl-4-hydroxyphenyl)-2,2-bis(4-hydroxyphenyl)propane,
3-(3-methyl-4-hydroxyphenyl)-1,3-bis(4-
10 hydroxyphenyl)butane,
1-(3-methyl-4-hydroxyphenyl)-3,3-bis(4-hydroxyphenyl)butane,
4-(3-methyl-4-hydroxyphenyl)-1,4-bis(4-
hydroxyphenyl)pentane,
15 1-(3-methyl-4-hydroxyphenyl)-4,4-bis(4-
hydroxyphenyl)pentane,
1,2-bis(3-methyl-4-hydroxyphenyl)-2-(4-hydroxyphenyl)propane,
3,3-bis(3-methyl-4-hydroxyphenyl)-1-(4-
20 hydroxyphenyl)butane,
1,3-bis(3-methyl-4-hydroxyphenyl)-3-(4-hydroxyphenyl)butane,
4,4-bis(3-methyl-4-hydroxyphenyl)-1-(4-
hydroxyphenyl)pentane,
25 1,4-bis(3-methyl-4-hydroxyphenyl)-4-(4-
hydroxyphenyl)pentane,
1,1,2-tris(3-methyl-4-hydroxyphenyl)ethane,
1,2,2-tris(3-methyl-4-hydroxyphenyl)propane,
1,1,3-tris(3-methyl-4-hydroxyphenyl)propane,
30 1,3,3-tris(3-methyl-4-hydroxyphenyl)butane,
1,1,4-tris(3-methyl-4-hydroxyphenyl)butane,
1,4,4-tris(3-methyl-4-hydroxyphenyl)pentane, and
4,4'-[4-(4-hydroxyphenyl)-sec-butylidene]bis(2-
methylphenol).
35 [0040]
Examples of the compound having four or more phenolic
31

hydroxy groups include
phenolic hydroxy groups,
bis[2-hydroxy-3-(2-hydroxy-5-methylbenzyl)-5-
methylphenyl]methane,
5 4,6-bis[(4-hydroxyphenyl)methyl)-1,3-benzenediol,
4,4'-[(3,4-dihydroxyphenyl)methylene]bis(2,6-dimethylphenol),
4,4'-[(3,4-dihydroxyphenyl)methylene]bis(2-cyclohexyl-
5-methylphenol),
10 4,4'-[(3,4-dihydroxyphenyl)methylene]bis(2-
methylphenol),
4,4'-[(3,4-dihydroxyphenyl)methylene]bis(2,3,6-trimethylphenol),
1,1,2,2-tetrakis(4-hydroxyphenyl)ethane,
15 1,1,2,2-tetrakis(4-hydroxy-3-methylphenyl)ethane,
1,1,2,2-tetrakis(3,5-dimethyl-4-hydroxyphenyl)ethane,
1,1,4,4-tetrakis(3,5-dimethyl-4-hydroxyphenyl)benzene,
2,2'-bis[4,4-(4-hydroxy-3-
methylphenyl)cyclohexyl]propane,
20 2,2'-[(3,4-dihydroxyphenyl)methylene]bis(3,5-
dimethylphenol),
3,6-bis[(3,5-dimethyl-4-hydroxyphenyl)methyl)catechol,
4,6-bis[(3,5-dimethyl-4-hydroxyphenyl)methyl)-1,3-
benzenediol,
25 2,2'-[(3,4-dihydroxyphenyl)methylene]bis(3,5,6-
trimethylphenol),
4,4'-[(3,4-dihydroxyphenyl)methylene]bis(2-cyclohexylphenol),
bis[3-(2-hydroxybenzyl)-4-hydroxy-5-
30 methylphenyl]methane,
bis[3-(3-hydroxybenzyl)-4-hydroxy-5-methylphenyl]methane,
bis[3-(4-hydroxybenzyl)-4-hydroxy-5-
methylphenyl]methane,
35 bis[3-(2-hydroxybenzyl)-2-hydroxy-5-
methylphenyl]methane,
32

bis[3-(2-hydroxybenzyl)-3-hydroxy-5-methylphenyl]methane,
bis[3-(2-hydroxybenzyl)-4-hydroxy-5-
methylphenyl]methane,
5 bis[3-(3-hydroxy-2-methylbenzyl)-2-hydroxy-5-
methylphenyl]methane,
bis[3-(4-hydroxy-3-methylbenzyl)-2-hydroxy-5-methylphenyl]methane,
bis[3-(3-hydroxy-4-methylbenzyl)-2-hydroxy-5-10 methylphenyl]methane,
bis[3-(2-hydroxy-3-methylbenzyl)-2-hydroxy-5-methylphenyl]methane,
α,α',α",α'"-tetraxis(4-hydroxyphenyl)benzene,
bis[3-(3,6-dimethyl-2-hydroxybenzyl)-2-hydroxy-5-15 methylphenyl]methane,
[3-(3,6-dimethyl-2-hydroxybenzyl)-2-hydroxy-5-
methylphenyl][3-(2,5-dimethyl-4-hydroxybenzyl)-2-hydroxy-5-
methylphenyl]methane,
bis[3-(2,5-dimethyl-4-hydroxybenzyl)-2-hydroxy-5-20 methylphenyl]methane,
bis[3-(3,5-dimethyl-4-hydroxybenzyl)-2-hydroxy-5-methylphenyl]methane,
bis[3-(2-hydroxy-3,4,6-trimethylbenzyl)-2-hydroxy-5-
methylphenyl]methane,
25 bis[2-hydroxy-3-(4-hydroxy-2,3,5-trimethylbenzyl)-5-
methylphenyl]methane,
4,4',4",4'"-tetrakis(4-hydroxyphenyl)-1,1'-bicyclohexyl,
2,2'-bis[4,4-bis(4-hydroxyphenyl)cyclohexyl]propane,
4,4',4",4'"-tetrakis(4-hydroxy-3-methylphenyl)-1,1'-30 bicyclohexyl,
bis[3-(5-cyclohexyl-4-hydroxy-2-methylbenzyl)-4-hydroxy-5-methylphenyl]methane,
4,4',4",4'"-tetrakis(3,5-dimethyl-4-hydroxyphenyl)-1,1'-
bicyclohexyl,
35 1,1-bis[3-(2-hydroxy-5-methylbenzyl)-5-cyclohexyl-4-
hydroxyphenyl]cyclohexane,
33

1,1-bis[3-(3,5-dimethyl-4-hydroxybenzyl)-5-cyclohexyl-4-hydroxyphenyl]cyclohexane,
1,1-bis[3-(5-cyclohexyl-4-hydroxy-2-methylbenzyl)-5-
cyclohexyl-4-hydroxyphenyl]cyclohexane,
5 4,6-bis[α-methyl-(4-hydroxyphenyl)benzyl-1,3-
benzenediol,
2,2-bis[3-(4-hydroxy-3-methylbenzyl)-4-hydroxy-5-methylphenyl]propane,
2,6-bis[(3,5-dimethyl-4-hydroxyphenyl)benzyl]-4- α-
10 methyl-(3,5-dimethyl-4-hydroxyphenyl)benzyl]phenol,
4,4',4",4'"-tetrakis(4-hydroxy-3-isopropylphenyl)-1,1'-bicyclohexyl,
4,4'-bis[(3,4-dihydroxyphenyl)methylene]bis(2-
isopropylphenol)
15 2,4,6-tris(4-hydroxybenzyl)-1,3-benzenediol,
4,6-bis(3,5-dimethyl-4-hydroxybenzyl)pyrogallol,
3,3'-[(2-hydroxyphenyl)methylene]bis(5-methylcatechol),
2,6-bis(2,4-dihydroxybenzyl)-4-ethylphenol,
2,4-bis(2,4-dihydroxybenzyl)-6-cyclohexylphenol,
20 2,6-bis(5-tert-butyl-2,3-dihydroxybenzyl)-4-
methylphenol,
2,4,6-tris(3,5-dimethyl-4-hydroxybenzyl)resorcin,
2,4,6-tris(3,5-dimethyl-2-hydroxybenzyl)resorcin,
2,6-bis(2,4-dihydroxybenzyl)-3,4-dimethylphenol,
25 2,6-bis[3-(2-hydroxy-5-methylbenzyl)-2,5-dimethyl-4-
hydroxybenzyl]-3,4-dimethylphenol,
4,6-bis(α-methyl-4-hydroxybenzyl)pyrogallol,
4,4'-[1-{4-[1-(3,5-bis(4-hydroxybenzyl)-4-
hydroxyphenyl)-1-methylethyl]phenyl}etylidene]bis[2,6-bis(4-
30 hydroxybenzyl)phenol],
4,4'-[1-{4-[1-(3,5-bis(4-hydroxy-3-methylbenzyl)-4-hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bis[2,6-bis(4-hydroxy-3-methylbenzyl)phenol],
4,4'-[1-{4-[1-(3,5-bis(3,5-dimethyl-4-hydroxybenzyl)-4-
35 hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bis[2,6-
bis(3,5-dimethyl-4-hydroxybenzyl)phenol],
34

4,4'-[1-{4-[1-(3,5-bis(4-hydroxy-2,3,6-trimethylbenzyl)-4-hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bis[2,6-bis(4-hydroxy-2,3,6-trimethylbenzyl)phenol],
bis[5-(2,4-dihydroxybenzyl)-4-hydroxy-3-5 methylphenyl]methane,
bis[3-(2,4-dihydroxybenzyl)-2,5-dimethyl-4-hydroxyphenyl]methane,
bis[3-(2,4-dihydroxy-3-methylbenzyl)-2,5-dimethyl-4-
hydroxyphenyl]methane,
10 bis[5-(4-hydroxybenzyl)-2,3,4-
trihydroxyphenyl]methane,
1,1-bis[5-(4-hydroxybenzoyl)-2,3,4-trihydroxyphenyl]ethane,
3,3',5,5'-tetrakis(4-hydroxybenzyl)-4,4'-15 dihydroxybiphenyl,
3,3',5,5'-tetrakis(4-hydroxy-3-methylbenzyl)-4,4'-dihydroxybiphenyl,
3,3',5,5'-tetrakis(2-hydroxy-5-methylbenzyl)-4,4'-
dihydroxybiphenyl,
20 3,3',5,5'-tetrakis(3,5-dimethyl-4-hydroxybenzyl)-4,4'-
dihydroxybiphenyl,
bis[3-(α,α-bis(4-hydroxy-3-methylphenyl)methyl-4-hydroxyphenyl]methane,
bis[3,5-bis(2-hydroxy-5-methylbenzyl)-4-25 hydroxyphenyl]methane,
4,4',4"-ethyridinetris{[2-(2-hydroxy-5-methyl)benzyl]-6-methylphenol},
2,2-bis[3,5-bis(2-hydroxy-5-
methylphenylmethyl)phenyl]propane,
30 bis[3-(α,α-bis(2,5-dimethyl-4-hydroxyphenyl)methyl-4-
hydroxyphenyl]methane,
bis[5-(3,5-dimethyl-4-hydroxybenzyl)-2,3,4-trihydroxyphenyl]methane,
bis[3-(2,3,4-trihydroxybenzyl)-2,5-dimethyl-4-35 hydroxyphenyl]methane,
1,1-bis[3-(2,3,4-trihydroxybenzyl)-5-cyclohexyl-4-
35

hydroxyphenyl]cyclohexane,
1,8,15,22-tetranonyl-3,5,10,12,17,19,24,26-octahydroxy[1,1,1,1]-metacyclophane,
4,4'-[1-{4-[1-(3,5-bis(4-hydroxy-2-methylbenzyl)-4-5 hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bis[2,6-bis(4-hydroxy-2-methylbenzyl)phenol],
4,4'-[1-{4-[1-(3,5-bis(2-hydroxy-5-methylbenzyl)-4-
hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bis[2,6-bis(2-
hydroxy-5-methylbenzyl)phenol],
10 4,4'-[1-{4-[1-(3,5-bis(3-ethyl-4-hydroxybenzyl)-4-
hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bis[2,6-bis(3-ethyl-4-hydroxybenzyl)phenol],
4,4'-[1-{4-[1-(3,5-bis(3,5-dimethyl-2-hydroxyphenyl)-4-hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bis[2,6-15 bis(3,5-dimethyl-2-hydroxyphenyl)phenol],
4,4'-[1-{4-[1-(3,5-bis(4-hydroxy-3-isopropylphenyl)-4-hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bis[2,6-bis(4-hydroxy-3-isopropylphenyl)phenol],
bis[3-(α,α-bis(3,5-dimethyl-4-hydroxyphenyl)methyl-4-20 hydroxyphenyl]methane,
bis[3-(α,α-bis(5-cyclohexyl-4-hydroxy-2-methylphenyl)methyl-4-hydroxyphenyl]methane,
4,4'-[4-hydroxy-3,5-bis(2-
hydroxybenzyl)methylene]bis[2,6-bis(2-hydroxybenzyl)]phenol,
25 4,4'-[4-hydroxy-3,5-bis(4-
hydroxybenzyl)methylene]bis[2,6-bis(4-hydroxybenzyl)]phenol, 4,4',4"-ethylidinetris[2,6-bis(2-hydroxybenzyl)phenol], 4,4',4"-ethylidinetris[2,6-bis(4-hydroxybenzyl)phenol], 2,2-bis[3,5-bis(4-hydroxy-3-methylbenzyl)-4-30 hydroxyphenyl]propane,
1,8,15,22-tetraethyl-3,5,10,12,17,19,24,26-octahydroxy[1,1,1,1]-metacyclophane,
α,α',α",α'"-tetrakis(3,5-dimethyl-4-hydroxyphenyl)-1,4-
dimethylbenzene,
35 4,4'-[1-{4-[1-(3,5-bis(2-hydroxy-5-isopropylphenyl)-4-
hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bis[2,6-bis(2-
36

hydroxy-5-isopropylphenyl)phenol],
4,4'-[1-{4-[1-(3,5-bis(4-hydroxy-2,3,5-trimethylphenyl)-
4-hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bis[2,6-
bis(4-hydroxy-2,3,5-trimethylphenyl)phenol],
5 4,4'-[1-{4-[1-(3,5-bis(3-sec-butyl-4-hydroxyphenyl)-4-
hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bis[2,6-bis(3-sec-butyl-4-hydroxyphenyl)phenol],
4,4'-[1-{4-[1-(3,5-bis(3-tert-butyl-4-hydroxyphenyl)-4-
hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bis[2,6-bis(3-
10 tert-butyl-4-hydroxyphenyl)phenol],
2,6-bis{[3-(2,4-dihydroxybenzyl)-2,5-dimethyl-4-hydroxy]benzyl}-4-methylphenol,
1,1-bis[5-(2,4-dihydroxybenzyl)-3-cyclohexyl-4-
hydroxyphenyl]cyclohexane,
15 1,1-bis[5-(2,3,4-trihydroxybenzyl)-3-cyclohexyl-4-
hydroxyphenyl]cyclohexane, and
2,2-bis[4,4',4",4'"-tetrakis(3,5-dihydroxymethyl-4-
hydroxyphenyl)cyclohexyl]propane.
[0041]
20 Examples of the carboxylic acid and the derivative
thereof include
3,5-di(α-methylbenzyl)salicylic acid,
4-(2-p-methoxyphenyloxyethoxy)salicylic acid,
4-hydroxyphenylbenzoic acid,
25 p-chlorobenzoic acid,
4-[2-(p-methoxyphenoxy)ethyloxy]salicylic acid, 4-[3-(p-tolylsulfonyl)propyloxy]salicylic acid,
5-[p-(2-p-methoxyphenoxyethoxy)cumyl]salicylic acid,
4-octyloxycarbonylaminosalicylic acid,
30 3,5-distyrene salicylic acid,
N-(p-toluenesulfonyl)-glycine,
N-(p-toluenesulfonyl)-alanine,
N-(p-toluenesulfonyl)-β-alanine,
N-phenylaminocarbonyl-glycine,
35 N-phenylaminocarbonyl-valine,
N-(m-tolylaminocarbonyl)-phenylalanine,
37

N-(m-tolylaminocarbonyl)-cysteine-S-benzyl,
N-(m-tolylaminocarbonyl)-methionine,
N-(m-tolylaminocarbonyl)-tyrosine,
N-(p-tolylaminocarbonyl)-phenylalanine,
5 N-(p-tolylaminocarbonyl)-cysteine-S-benzyl,
N-(p-tolylaminocarbonyl)-methionine,
N-(p-tolylaminocarbonyl)-methionine,
N-(phenylaminocarbonyl)-methionine,
N-(p-tolylaminocarbonyl)-tyrosine,
10 N-(m-tolylaminocarbonyl)-methionine,
N-(p-tolylaminocarbonyl)-methionine,
N-(phenylaminocarbonyl)-methionine,
N-(m-tolylaminocarbonyl)-valine,
N-(m-tolylaminocarbonyl)-phenylglycine,
15 N-(m-tolylaminocarbonyl)-tyrosine,
2-O-(phenylaminocarbonyl)-mandelic acid,
2-O-(p-tolylaminocarbonyl)-mandelic acid,
2-O-(m-tolylaminocarbonyl)-mandelic acid,
2-O-(o-tolylaminocarbonyl)-mandelic acid,
20 2-O-(1-naphthylaminocarbonyl)-mandelic acid,
2-O-(3-isopropenyl-α,α-dimethylbenzylaminocarbonyl)-mandelic acid,
2-O-(benzylaminocarbonyl)-mandelic acid,
2-O-(phenethylaminocarbonyl)-mandelic acid,
25 2-O-(phenylaminocarbonyl)-lactic acid,
2-O-(p-tolylaminocarbonyl)-lactic acid,
2-O-(m-tolylaminocarbonyl)-lactic acid,
2-O-(o-tolylaminocarbonyl)-lactic acid,
2-O-(1-naphthylaminocarbonyl)-lactic acid,
30 2-O-(3-isopropenyl-α,α-dimethylbenzylaminocarbonyl)-
lactic acid,
2-O-(benzylaminocarbonyl)-lactic acid, and
2-O-(phenethylaminocarbonyl)-lactic acid.
[0042]
35 Examples of the acidic phosphate ester compound include
methyl acid phosphate, ethyl acid phosphate, butyl acid
38

phosphate, butoxyethyl acid phosphate, 2-ethylhexyl acid
phosphate, isodecyl acid phosphate, isotridecyl acid phosphate,
oleyl acid phosphate, tetracosyl acid phosphate, monobutyl
phosphate, dibutyl phosphate, monoisodecyl phosphate, and
5 bis(2-ethylhexyl)phosphate.
[0043]
Although the compounds having phenolic hydroxy groups
can develop the thermochromic properties most effectively, it is
also possible to use compounds selected from the group
10 consisting of aromatic carboxylic acids, aliphatic carboxylic acids
having 2 to 5 carbon atoms, metal salts of carboxylic acids, acidic
phosphoric esters and metal salts thereof, and 1,2,3-triazole and
derivatives thereof.
[0044]
15 The component (c) of the reaction medium which
reversibly induces an electron transfer reaction between the
component (a) and the component (b) in a specific temperature
range will be described. Examples of the component (c) include
esters, ketones, ethers, alcohols, and acid amides.
20 [0045]
As the component (c), there may be used a carboxylic acid
ester compound which discolors with showing a large hysteresis
characteristic with regard to a color density-temperature curve (a
curve plotting a change in color density with a temperature
25 change is different between the case where the temperature is
changed from a low temperature side to a high temperature side
and the case where the temperature is changed from a high
temperature side to a low temperature side), is capable of
forming a reversibly thermochromic composition having a color-
30 memory property, and shows a ΔT value (melting point-cloud
point) ranging from 5°C to less than 50°C, for example, a
carboxylic acid ester containing a substituted aromatic ring in the
molecule, an ester of a carboxylic acid containing an
unsubstituted aromatic ring with an aliphatic alcohol having 10 or
35 more carbon atoms, a carboxylic acid ester containing a
cyclohexyl group in the molecule, an ester of a fatty acid having
39

6 or more carbon atoms with an unsubstituted aromatic alcohol
or phenol, an ester of a fatty acid having 8 or more carbon atoms
with a branched aliphatic alcohol, an ester of a dicarboxylic acid
with an aromatic alcohol or a branched aliphatic alcohol, dibenzyl
5 cinnamate, heptyl stearate, didecyl adipate, dilauryl adipate,
dimyristyl adipate, dicetyl adipate, distearyl adipate, trilaurin, trimyristin, tristearin, dimyristin, or distearin. [0046]
A fatty acid ester compound obtained from an aliphatic
10 monohydric alcohol having an odd number not less than 9 of
carbon atoms, and an aliphatic carboxylic acid having an even number of carbon atoms, and a fatty acid ester compound with a total carbon number of 17 to 23 to be obtained from n-pentyl alcohol or n-heptyl alcohol and an aliphatic carboxylic acid having
15 an even number from 10 to 16 of carbon atoms, are also effective.
[0047]
Specific examples thereof include n-pentadecyl acetate, n-tridecyl butyrate, n-pentadecyl butyrate, n-undecyl caproate, n-tridecyl caproate, n-pentadecyl caproate, n-nonyl caprylate,
20 n-undecyl caprylate, n-tridecyl caprylate, n-pentadecyl
caprylate, n-heptyl caprate, n-nonyl caprate, n-undecyl caprate, n-tridecyl caprate, n-pentadecyl caprate, n-pentyl laurate, n-heptyl laurate, n-nonyl laurate, n-undecyl laurate, n-tridecyl laurate, n-pentadecyl laurate, n-pentyl myristate, n-heptyl
25 myristate, n-nonyl myristate, n-undecyl myristate, n-tridecyl
myristate, n-pentadecyl myristate, n-pentyl palmitate, n-heptyl palmitate, n-nonyl palmitate, n-undecyl palmitate, n-tridecyl palmitate, n-pentadecyl palmitate, n-nonyl stearate, n-undecyl stearate, n-tridecyl stearate, n-pentadecyl stearate, n-nonyl
30 eicosanoate, n-undecyl eicosanoate, n-tridecyl eicosanoate, n-
pentadecyl eicosanoate, n-nonyl behenate, n-undecyl behenate, n-tridecyl behenate, and n-pentadecyl behenate. [0048]
As the ketones, aliphatic ketones with a total carbon
35 number of 10 or more are effectively employed. Examples
thereof include 2-decanone, 3-decanone, 4-decanone, 2-40

undecanone, 3-undecanone, 4-undecanone, 5-undecanone, 2-
dodecanone, 3-dodecanone, 4-dodecanone, 5-dodecanone, 2-
tridecanone, 3-tridecanone, 2-tetradecanone, 2-pentadecanone,
8-pentadecanone, 2-hexadecanone, 3-hexadecanone, 9-
5 heptadecanone, 2-pentadecanone, 2-octadecanone, 2-
nonadecanone, 10-nonadecanone, 2-eicosanone, 11-
eicosanone, 2-heneicosanone, 2-docosanone, laurone, and
stearone.
[0049]
10 Furthermore, examples thereof include aryl alkyl ketones
with a total carbon number of 12 to 24 such as n-
octadecanophenone, n-heptadecanophenone, n-
hexadecanophenone, n-pentadecanophenone, n-
tetradecanophenone, 4-n-dodecaacetophenone, n-
15 tridecanophenone, 4-n-undecanoacetophenone, n-
laurophenone, 4-n-decanoacetophenone, n-undecanophenone,
4-n-nonylacetophenone, n-decanophenone, 4-n-
octylacetophenone, n-nonanophenone, 4-n-heptylacetophenone,
n-octanophenone, 4-n-hexylacetophenone, 4-n-
20 cyclohexylacetophenone, 4-tert-butylpropiophenone, n-
heptaphenone, 4-n-pentylacetophenone, cyclohexyl phenyl
ketone, benzyl n-butyl ketone, 4-n-butylacetophenone, n-
hexanophenone, 4-isobutylacetophenone, 1-acetonaphthone, 2-
acetonaphthone, and cyclopentyl phenyl ketone.
25 [0050]
As the ethers, aliphatic ethers with a total carbon number
of 10 or more are effectively employed. Examples thereof
include dipentyl ether, dihexyl ether, diheptyl ether, dioctyl
ether, dinonyl ether, didecyl ether, diundecyl ether, didodecyl
30 ether, ditridecyl ether, ditetradecyl ether, dipentadecyl ether,
dihexadecyl ether, dioctadecyl ether, decanediol dimethyl ether,
undecanediol dimethyl ether, dodecanediol dimethyl ether,
tridecanediol dimethyl ether, decanediol diethyl ether, and
undecanediol diethyl ether.
35 [0051]
As the alcohols, an aliphatic monohydric saturated alcohol
41

having 10 or more carbon atoms is effectively employed. Examples thereof include decyl alcohol, undecyl alcohol, dodecyl alcohol, tridecyl alcohol, tetradecyl alcohol, pentadecyl alcohol, hexadecyl alcohol, heptadecyl alcohol, octadecyl alcohol, eicosyl 5 alcohol, and dococyl alcohol. [0052]
As the acid amides, there may be mentioned hexanamide, heptanamide, octanamide, nonanamide, decanamide, undecanamide, laurylamide, tridecanamide, 10 myristamide, palmitamide, stearamide, and docosanamide. [0053]
As the component (c), a compound expressed by the following Formula (1) may be used: [Chem. 1]
XNP^ R1 /r^X1
C )/^CH2^CH~O~C j) (1)
15 (Y1 p1 q ^(Y1 p1
(wherein R1 represents a hydrogen atom or a methyl group, q1 represents an integer of 0 to 2, one of X1 represents -(CH2)kOCOR' or -(CH2)kCOOR', the other represents a hydrogen atom; k represents an integer of 0 to 2; R' represents an alkyl or
20 alkenyl group having 4 or more carbon atoms, each Y1 independently represents an alkyl group having 1 to 4 carbon atoms, a methoxy group, or a halogen, and each p1 independently represents an integer of 0 to 3.) [0054]
25 Among compounds represented by the Formula (1), those
in which R1 is a hydrogen atom are suitable, because a reversibly thermochromic composition with a wider hysteresis width is obtainable, and those in which R1 is a hydrogen atom and m is 0 are more suitable.
30 [0055]
Among the compounds represented by the Formula (1),
compounds represented by the following Formula (1a) are used
more preferably:
42

[Chem. 1a]
O CH2-O—(i J)—CH2-CH2—O-C-R1a (1a)
(wherein R1a represents an alkyl or alkenyl group having 8 or more carbon atoms, preferably an alkyl group having 10 to 24 5 carbon atoms, and more preferably an alkyl group having 12 to 22 carbon atoms.) [0056]
Specific examples of the compound include 4-benzyloxyphenylethyl octanoate, 4-benzyloxyphenylethyl 10 nonanoate, 4-benzyloxyphenylethyl decanoate, 4-
benzyloxyphenylethyl undecanoate, 4-benzyloxyphenylethyl dodecanoate, 4-benzyloxyphenylethyl tridecanoate, 4-benzyloxyphenylethyl tetradecanoate, 4-benzyloxyphenylethyl pentadecanoate, 4-benzyloxyphenylethyl hexadecanoate, 4-15 benzyloxyphenylethyl heptadecanoate, and 4-benzyloxyphenylethyl octadecanoate. [0057]
Further, as the component (c), a compound represented by the following Formula (2) may be used: 20 [Chem. 2]
O^ .R2 ^C I O
C—(( J> (2)
(wherein R2 represents an alkyl or alkenyl group having 8 or more carbon atoms, each p2 independently represents an integer of 0 to 3, and each X2 independently represents an alkyl 25 group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or a halogen.) [0058]
Specific examples of the compound include 1,1-diphenylmethyl octanoate, 1,1-diphenylmethyl nonanoate, 1,1-
43

5
10

diphenylmethyl decanoate, 1,1-diphenylmethyl undecanoate, 1,1-diphenylmethyl dodecanoate, 1,1-diphenylmethyl tridecanoate, 1,1-diphenylmethyl tetradecanoate, 1,1-diphenylmethyl pentadecanoate, 1,1-diphenylmethyl hexadecanoate, 1,1-diphenylmethyl heptadecanoate, or 1,1-diphenylmethyl octadecanoate. [0059]
Furthermore, as the component (c), a compound
represented by the following Formula (3) may be used: [Chem. 3]

O
O CH2
X3)
C OCH2 CH2
p3
(3)
q3

(CH2)
O CH2
CH2 CH2
'X3
p3
CO O

15
20
25
30

(wherein each X3 independently represents an alkyl group having 1 to 4 carbon atoms, a methoxy group, or a halogen atom, each p3 independently represents an integer of 0 to 3, and q3 represents an integer of 1 to 20.) [0060]
Examples of the compound include diester of malonic acid with 2-[4-(4-chlorobenzyloxy)phenyl)]ethanol, diester of succinic acid with 2-(4-benzyloxyphenyl)ethanol, diester of succinic acid with 2-[4-(3-methylbenzyloxy)phenyl)]ethanol, diester of glutaric acid with 2-(4-benzyloxyphenyl)ethanol, diester of glutaric acid with 2-[4-(4-chlorobenzyloxy)phenyl)]ethanol, diester of adipic acid with 2-(4-benzyloxyphenyl)ethanol, diester of pimelic acid with 2-(4-benzyloxyphenyl)ethanol, diester of suberic acid with 2-(4-benzyloxyphenyl)ethanol, diester of suberic acid with 2-[4-(3-methylbenzyloxy)phenyl)]ethanol, diester of suberic acid with 2-[4-(4-chlorobenzyloxy)phenyl)]ethanol, diester of suberic acid with 2-[4-(2,4-dichlorobenzyloxy)phenyl)]ethanol, diester of azelaic acid with 2-(4-benzyloxyphenyl)ethanol, diester of
44

sebacic acid with 2-(4-benzyloxyphenyl)ethanol, diester of 1,10-
decanedicarboxylic acid with 2-(4-benzyloxyphenyl)ethanol,
diester of 1,18-octadecanedicarboxylic acid with 2-(4-
benzyloxyphenyl)ethanol, and diester of 1,18-octadecane-
5 dicarboxylic acid with 2-[4-(2-methylbenzyloxy)phenyl)]ethanol.
[0061]
Furthermore, as the component (c), a compound represented by the following Formula (4) may be used: [Chem. 4]

O
R4-C-O-fCH2]-O
V 7p4
O (4)
O-fCH2^-O-C-R4
V 'p4
10
(wherein each R4 independently represents an alkyl group having 1 to 21 carbon atoms or an alkenyl group, and each p4 independently represents an integer of 1 to 3.) [0062]
15 Examples of the compound include diester of capric acid
with 1,3-bis(2-hydroxyethoxy)benzene, diester of undecanoic acid with 1,3-bis(2-hydroxyethoxy)benzene, diester of lauric acid with 1,3-bis(2-hydroxyethoxy)benzene, diester of myristic acid with 1,3-bis(2-hydroxyethoxy)benzene, diester of palmitic
20 acid with 1,3-bis(2-hydroxyethoxy)benzene, diester of
cyclohexanecarboxylic acid with 1,3-bis(2-hydroxyethoxy)benzene, diester of cyclohexanepropionic acid with 1,3-bis(2-hydroxyethoxy)benzene, diester of butyric acid with 1,4-bis(hydroxymethoxy)benzene, diester of isovaleric acid
25 with 1,4-bis(hydroxymethoxy)benzene, diester of acetic acid
with 1,4-bis(2-hydroxyethoxy)benzene, diester of propionic acid with 1,4-bis(2-hydroxyethoxy)benzene, diester of valeric acid with 1,4-bis(2-hydroxyethoxy)benzene, diester of caproic acid with 1,4-bis(2-hydroxyethoxy)benzene, diester of carpylic acid
30 with 1,4-bis(2-hydroxyethoxy)benzene, diester of capric acid
with 1,4-bis(2-hydroxyethoxy)benzene, diester of lauric acid with 1,4-bis(2-hydroxyethoxy)benzene, diester of myristic acid with 1,4-bis(2-hydroxyethoxy)benzene, and diester of
45

cyclohexanepropionic acid with 1,4-bis(2-
hydroxyethoxy)benzene.
[0063]
Furthermore, as the component (c), a compound 5 represented by the following Formula (5) may be used: [Chem. 5]
O II C-O-CH2-CH2-O
CH2q5 X5 p5 (5)
C-O-CH2-CH2-O—0^ j)
O ^X5p5
(wherein each X5 independently represents an alkyl group
having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon 10 atoms, or a halogen atom, each p5 independently represents an
integer of 0 to 3, and q5 represents an integer of 1 to 20.)
[0064]
Examples of the compound include diester of succinic acid
with 2-phenoxyethanol, diester of suberic acid with 2-15 phenoxyethanol, diester of sebacic acid with 2-phenoxyethanol,
diester of 1,10-decanedicarboxylic acid with 2-phenoxyethanol,
or diester of 1,18-octadecanedicarboxylic acid with 2-
phenoxyethanol.
[0065]
20 Furthermore, as the component (c), a compound
represented by the following Formula (6) may be used:
[Chem. 6]
v i/ w it i vCH2-q C-O-R6 (6)
O X6
(wherein R6 represents an alkyl group having 4 to 22
25 carbon atoms, a cycloalkyl alkyl group, a cycloalkyl group, or an
alkenyl group having 4 to 22 carbon atoms, X6 represents a
hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an
46

alkoxy group having 1 to 4 carbon atoms, or a halogen atom, and
q6 represents 0 or 1.)
[0066]
Examples of the compound include decyl 4-
5 phenylbenzoate, lauryl 4-phenylbenzoate, myristyl 4-
phenylbenzoate, cyclohexylethyl 4-phenylbenzoate, octyl 4-
biphenylacetate, nonyl 4-biphenylacetate, decyl 4-
biphenylacetate, lauryl 4-biphenylacetate, myristyl 4-
biphenylacetate, tridecyl 4-biphenylacetate, pentadecyl 4-
10 biphenylacetate, cetyl 4-biphenylacetate, cyclopentyl 4-
biphenylacetate, cyclohexylmethyl 4-biphenylacetate, hexyl 4-
biphenylacetate, and cyclohexylmethyl 4-biphenylacetate.
[0067]
Furthermore, as the component (c), a compound
15 represented by the following Formula (7) may be used:
[Chem. 7]
OY7
R7O—(L ))—C-O-CH-CH2-O—(l J) (7)
(wherein R7 represents an alkyl group having 3 to 18 carbon atoms or an aliphatic acyl group having 3 to 18 carbon
20 atoms, X7 represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 or 2 carbon atoms, or a halogen atom, Y7 represents a hydrogen atom or a methyl group, and Z7 represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 or 2 carbon atoms,
25 or a halogen atom). [0068]
Examples of the compound include phenoxyethyl 4-butoxybenzoate, phenoxyethyl 4-pentyloxybenzoate, phenoxyethyl 4-tetradecyloxybenzoate, an ester of
30 phenoxyethyl 4-hydroxybenzoate and dodecanoic acid, and a dodecyl ether of phenoxyethyl vanilliate. [0069]
Furthermore, as the component (c), a compound
represented by the following Formula (8) may be used:
47

[Chem. 8]

O > v O
C-O—(M)- C-O-R8 (9)
QVfCH2^—C-O—(T j)— p9 / sC$>~s/
(X8 q8 p9 (X8';r8
(wherein R8 represents an alkyl group having 4 to 22
carbon atoms, an alkenyl group having 4 to 22 carbon atoms, a
5 cycloalkylalkyl group, or a cycloalkyl group, each X8
independently represents an alkyl group, an alkoxy group, or a
halogen atom, p8 represents 0 or 1, q8 represents 0 to 5, and r8
represents 0 to 4.)
[0070]
10 Examples of the compound include a benzoic acid ester of
octyl p-hydroxybenzoate, a benzoic acid ester of decyl p-hydroxybenzoate, a p-methoxybenzoic acid ester of heptyl p-hydroxybenzoate, an o-methoxybenzoic acid ester of dodecyl p-hydroxybenzoate, and a benzoic ester of cyclohexylmethyl p-15 hydroxybenzoate. [0071]
Furthermore, as the component (c), a compound represented by the following Formula (9) may be used: [Chem. 9] O
R9-C-O(CH2CH2O} (( )) (C ))—X9 (10)
20
p9 \^^7 \^^7
(wherein R9 represents an alkyl group having 3 to 17
carbon atoms, a cycloalkyl group having 3 to 8 carbon atoms, or
a cycloalkyl alkyl group having 5 to 8 carbon atoms, X9 represents
a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, a
25 methoxy group, an ethoxy group, or a halogen atom, and p9
represents an integer of 1 to 3.) [0072]
Examples of the compound include diester of 4-
phenylphenol ethylene glycol ether and cyclohexanecarboxylic
30 acid, diester of 4-phenylphenol diethylene glycol ether and lauric
acid, diester of 4-phenylphenol triethylene glycol ether and
48

cyclohexanecarboxylic acid, diester of 4-phenylphenol ethylene
glycol ether and octanoic acid, diester of 4-phenylphenol ethylene
glycol ether and nonanoic acid, diester of 4-phenylphenol
ethylene glycol ether and decanoic acid, and diester of 4-
5 phenylphenol ethylene glycol ether and myristic acid.
[0073]
As an electron-accepting compound, a microcapsule pigment encapsulating a reversibly thermochromic composition of heat color-developing type (a color is developed by heating
10 and lost by cooling) using a specific alkoxyphenol compound
having straight chain or side chain alkyl group having 3 to 18 carbon atoms (JP H11-129623A, JP H11-5973 A), a specific hydroxybenzoic ester (JP 2001-105732 A), a gallic ester (JP S51-44706B, JP 2003-253149 A) or the like may be applied.
15 [0074]
Though the ratio of the components (a), (b) and (c) to be mixed depends on the concentration, discoloration temperature, discoloration mode and kind of each component, the component ratio at which desired discoloration characteristics can be
20 generally obtained is within the range of 0.1 to 50 parts by mass,
preferably 0.5 to 20 parts by mass of the component (b), and within the range of 1 to 800 parts by mass, preferably from 5 to 200 parts by mass of the component (c), based on 1 part by mass of the component (a).
25 [0075]
In this regard, it is also possible to cause interchangeable color change from a color (1) to a color (2) by incorporating a coloring agent such as a non-thermochromic dyestuff or pigment into the microcapsule pigment or ink.
30 [0076]
Although a method of encapsulating the reversibly
thermochromic composition in a microcapsule is not particularly
limited, examples of the method include interfacial
polymerization, interfacial polycondensation, in situ
35 polymerization, submerged coat hardening, phase separation
from an aqueous solution, phase separation from an organic
49

solvent, melt dispersion cooling, aerial suspension coating and
spray drying. The method is selected as needed, depending on
the use purpose
[0077]
5 Examples of the material of the capsule include organic
resins such as epoxy resins, urea resins, urethane resins, and
isocyanate resins. In the present invention, since a surface of
pigment particles is composed of an organic material, excellent
properties are exhibited by three interactions with a polymer of
10 N-vinyl-2-pyrrolidone described later and glycerin. Therefore,
the material of the capsule needs to be an organic material.
[0078]
Further, the microcapsule can be put into practical use
after forming a secondary resin coating film on the surface
15 thereof in accordance with the intended use, so as to impart the
microcapsule with durability or to modify the surface properties.
[0079]
The microcapsule pigment preferably has an average
particle diameter of 0.1 to 5.0 μm, more preferably 0.1 to 4.0 μm,
20 and still more preferably 0.5 to 3.0 μm.
[0080]
The microcapsule pigment preferably satisfies the
requirement that a mass ratio between the reversibly
thermochromic composition and the wall membrane of the
25 microcapsule falls within the range of 7 : 1 to 1 : 1 (ratio by
mass), preferably 6 : 1 to 1 : 1.
[0081]
When the average particle diameter of the microcapsule
pigment exceeds 5.0 μm, it is difficult to obtain a smooth writing
30 feeling when the microcapsule pigment is used in a writing
instrument, and when an average value of a maximum outer
diameter is less than 0.1 μm, it becomes difficult to exhibit high-density color development.
[0082]
35 The microcapsule pigment having an average particle
diameter in the above range, particularly within the range of 0.5
50

to 3.0 μm, exhibits high-density color development, and a good
ejection property is easily obtained when the microcapsule
pigment is used in a writing instrument.
[0083]
5 When the ratio of the reversibly thermochromic
composition to the wall membrane is larger than the above range,
the thickness of the wall membrane becomes too thin, and
resistance to pressure and heat tends to decrease. When the
ratio of the wall membrane to the reversibly thermochromic
10 composition is larger than the above range, the color density and
vividness at the time of color development tend to decrease. [0084]
In the measurement of the average particle diameter, a
region of particles is determined using an image analysis type
15 particle size distribution measuring software “Mac-View”
manufactured by Mountech Co., Ltd., a projected area equivalent
circle diameter (Heywood diameter) is calculated from the area
of the region of particles, and the average particle diameter is
measured as an average particle diameter of particles equivalent
20 to an equal volume sphere based on the calculated value.
[0085]
When the particle diameter of all particles or most of the
particles exceed 0.2 μm, the average particle diameter can be
measured as an average particle diameter of particles equivalent
25 to an equal volume sphere by the Coulter method using a particle
size distribution analyzer (manufactured by Beckman-Coulter,
Inc., product name: Multisizer 4e). In addition, a volume-based
particle diameter and the average particle diameter (median
diameter) may be measured using a laser diffraction/scattering-
30 type particle size distribution analyzer (device name: LA-300,
manufactured by Horiba, Ltd.) after calibration based on the
numerical values measured using a standard sample or the
analyzer by the Coulter method.
[0086]
35
The ink composition according to the present invention
51

further includes a polymer of N-vinyl-2 pyrrolidone (hereinafter,
may be simply referred to as “PVP”.). In the ink composition
according to the present invention, PVP has an effect of
simultaneously completing various properties. Specifically,
5 there are an effect of adjusting a viscosity of the ink composition,
an effect of suppressing aggregation of the microcapsule pigment, an effect of improving fixability and adhesiveness of the ink component to paper, and the like. Furthermore, according to the study of the present inventors, it has been found that the ink
10 composition containing the microcapsule pigment has an effect of
suppressing drying up. For example, when the ink composition is used for a ballpoint pen or a marking pen, particularly for a knock-type ballpoint pen, its pen tip is placed in a situation where the pen tip is easy to dry. As a result, these writing instruments
15 may become unwritable. Although such a state is referred to as
dry-up, according to the present invention, by using PVP in a specific ink composition, the dry-up can be suppressed, and excellent writability can be achieved. [0087]
20 Although PVP is obtained by polymerizing N-vinyl -2-
pyrrolidone, it is necessary to use PVP having a degree of
polymerization of 2 to 20, and the degree of polymerization is
preferably 2 to 10 and more preferably 2 to 6. When the
polymerization degree is in such a range, an increase in the
25 viscosity of the ink composition and the aggregation of the
microcapsule pigment can be suppressed when water in the ink composition has evaporated. When PVP having an excessively high polymerization degree is used, the viscosity of the ink composition may also be excessively high, which adversely
30 affects writing performance, and thus attention is required.
[0088]

The ink composition according to the present invention further includes glycerin. Glycerin may be used as an organic
35 solvent or a viscosity modifier for a general ink composition.
However, in the present invention, glycerin exhibits a
52

conventionally unknown function. That is, when the
microcapsule pigment having the organic resin on the surface and
PVP coexist at a specific ratio, an interaction between three
components occurs, and remarkable improvement in writing
5 characteristics can be achieved.
[0089]

The ink composition according to the present invention is an aqueous ink composition and contains water as a main solvent.
10 The water used in the present invention is not particularly limited,
and for example, ion-exchanged water, ultrafiltration water, distilled water, or the like can be used. [0090]

15 In the present invention, a content (PMC) of the
microcapsule pigment with respect to a total mass of the ink composition needs to be 5 to 40% by mass, and is preferably 10 to 30% by mass, and more preferably, 10 to 25% by mass can be blended. For example, when the ink composition is used for
20 the applications such as a ballpoint pen, a blending amount of a
general pigment is less than 10% by mass with respect to a total amount of the ink composition; however, when a microcapsule pigment is used as a colorant, it is preferable to increase the blending amount for realizing sufficient color development. In
25 general, an ink composition having a high content of a
microcapsule pigment has a higher solid content than that of a general ink; and therefore, performance such as dry-up performance may be deteriorated. However, the ink composition according to the present invention solves such problems by
30 blending specific materials in specific ratios.
[0091]
In the present invention, a content (PPVP) of PVP with respect to the total mass of the ink composition is preferably 1 to 20% by mass, and more preferably 2 to 10% by mass. When
35 the content of PVP is within this range, dischargeability of the ink
composition from the pen tip is kept good, and a high handwriting
53

density can be achieved. [0092]
In the present invention, a content (PG) of glycerin is
preferably 1 to 20% by mass, and more preferably 2 to 10% by
5 mass with respect to the total mass of the ink composition.
When the content of glycerin is within this range, the
dischargeability of the ink composition from the pen tip is kept
good, and a clear handwriting can be formed.
[0093]
10 The ink composition of the present invention contains, as
essential components, a microcapsule pigment, PVP, glycerin, and
water, and a total content (PMC + PPVP + PG) of the microcapsule
pigment, PVP, and glycerin is preferably 20 to 50% by mass, and
more preferably 20 to 30% by mass. When PMC + PPVP + PG is
15 within this range, it is possible to suppress blurring at the start
of writing and achieve high writing characteristics while maintaining a high handwriting density. [0094]
In the present invention, the microcapsule pigment, PVP,
20 and glycerin are blended at a specific ratio. Specifically,
0.3 ≤ PMC/(PPVP + PG) ≤ 4, and
0.2 ≤ PPVP/PG ≤ 5
are required to be satisfied, and
0.5 ≤ PMC/(PPVP + PG) ≤ 2.5, or
25 0.3 ≤ PPVP/PG ≤ 2.5
is preferable. [0095]
In the present invention, the expected effect is exhibited
only when the microcapsule pigment, PVP, and glycerin are
30 blended so as to be within the above range. In other words, it
is considered that the effect of the present invention is exerted
by the interaction when the three components are combined at a
specific ratio. That is, the ink composition according to the
present invention simultaneously realizes writing density, dry-up
35 resistance, temporal stability, and the like. However, this is not
merely an expression of the effect of each component. For
54

example, PVP may be used as a material for improving the dry-
up resistance of the ink composition. However, according to the
study of the present inventors, it has been found that when
microcapsules and glycerin coexist, the dry-up resistance may
5 decrease by increasing an amount of PVP (see the section of
Examples). When a general inorganic pigment is used as the pigment, the effect of the present invention is not exhibited even if the pigment is blended at the ratio specified in the present invention. It is considered that since the microcapsule pigment
10 used in the present invention has an organic resin on the surface,
an interaction occurs between the organic resin and PVP and glycerin to improve temporal stability and writing characteristics. That is, in an ink composition in which a microcapsule pigment, PVP, and glycerin coexist, it has been unexpected that an ink
15 composition having excellent properties can be obtained when the
mutual ratio of these components is a specific ratio. [0096]

In the ink composition according to the present invention,
20 in addition to the essential components described above, optional
components can be combined as long as the effects of the present invention are not impaired. [0097]
As one of the optional components, a polysaccharide can
25 be used. The polysaccharides provide various effects, and
mainly provide effects such as adjustment of the ink viscosity (thickener), application of shear thinning (shear thinning agent), and improvement of dry-up resistant performance.
Here, the shear thinning is a property that has a high
30 viscosity when allowed to stand and the viscosity decreases when
a shear force is applied. Some ballpoint pens contain an ink composition generally called a gel ink. The gel ink composition has a high viscosity when allowed to stand without applying shear stress, and is stably held in the writing instrument. At the time
35 of writing, the viscosity of the ink near the ball is lowered by a
high shear force generated by high-speed rotation of the ball, so
55

that the ink is discharged from a gap between the ball and a ball
housing portion and transferred to a paper surface. A gel ink
can be obtained by combining the shear thinning agent with the
ink composition.
5 [0098]
When a polysaccharide is used, examples of suitable
polysaccharides include succinoglycan, xanthan gum, welan gum,
guar gum, locust bean gum, carrageenan, diutan gum and
derivatives thereof, cellulose derivatives, glycomannan,
10 thickening polysaccharides having gelling ability and extracted
from seaweed such as agar and carrageenan, and dextrin. Among these polysaccharides, succinoglycan and xanthan gum are preferable because they have a large effect of imparting the shear thinning, and succinoglycan is more preferable. As the
15 succinoglycan, those having an average molecular weight of
about 100 to 8,000,000 can be suitably used. Examples of the cellulose derivative include hydroxymethyl cellulose. [0099]
When the ink composition according to the present
20 invention contains succinoglycan or xanthan gum, a content of
succinoglycan or xanthan gum based on the total mass of the ink composition is preferably 0.01 to 1.0% by mass. When these contents are within the ranges, the ink discharge characteristics from the pen tip can be maintained at a high level, and the
25 aggregation of the microcapsule pigment can be suppressed.
[0100]
When dextrin or a cellulose derivative is used as the polysaccharide, it may be possible to simultaneously obtain a high improving effect such as adjustment of ink viscosity, application
30 of the shear thinning, and improvement of the dry-up resistant
performance. Among these polysaccharides, dextrin is
preferable because it has a large effect of improving the dry-up resistant performance. [0101]
35 The dextrin is preferably a sugar mixture containing an
octa- or higher starch-saccharified product and/or a reduced

CLAIMS

1.A reversibly thermochromic aqueous ink composition
comprising:
a reversibly thermochromic microcapsule pigment in which a reversibly thermochromic composition comprising (a) an electron-donating color-developing organic compound, (b) an electron-accepting compound, and (c) a reaction medium to determine an occurrence temperature of a coloring reaction of the component (a) and the component (b) is encapsulated in a microcapsule comprising an organic resin;
an N-vinyl-2-pyrrolidone polymer having a degree of polymerization of 2 to 20;
glycerin; and
water,
wherein when contents (% by mass) of the reversibly thermochromic microcapsule pigment, the N-vinyl-2-pyrrolidone polymer, and the glycerin with respect to a total mass of the ink composition are PMC, PPVP, and PG, respectively,
0.3 ≤ PMC/(PPVP + PG) ≤ 4, and
0.2 ≤ PPVP/PG ≤ 5.
2. The composition according to claim 1, wherein the PMC is 5 to 40% by mass.
3. The ink composition according to claim 1 or 2, wherein the PMC is 5 to 40% by mass, the PPVP is 1 to 20% by mass, and the PG is 1 to 20% by mass.
4. The ink composition according to any one of claims 1 to 3, wherein a total of the PMC, the PPVP, and the PG is 20 to 50% by mass.
5. The ink composition according to any one of claims 1 to 4, further comprising a polysaccharide.
95

6. The ink composition according to claim 5, wherein the polysaccharide is succinoglycan or xanthan gum.
7. A refill comprising the reversibly thermochromic aqueous ink composition according to any one of claims 1 to 6.
8. An aqueous ballpoint pen comprising the reversibly thermochromic aqueous ink composition according to any one of claims 1 to 6.
9. The aqueous ballpoint pen according to claim 8, comprising an in-and-out type mechanism.
10. The aqueous ballpoint pen according to claim 8 or 9, wherein a friction member is secured.