U.S. patent application number 12/301074 was filed with the patent office on 2009-07-23 for 2,5-di(methoxyanilino) terephthalic acid polymorphs and quinacridones realized therefrom.
Invention is credited to John Britanak, Daphne Rice, Edward H. Sung, Brian Thompson, Tracie Tibbs, Wengan Wu.
Application Number | 20090186200 12/301074 |
Document ID | / |
Family ID | 38529657 |
Filed Date | 2009-07-23 |
United States Patent
Application |
20090186200 |
Kind Code |
A1 |
Thompson; Brian ; et
al. |
July 23, 2009 |
2,5-DI(METHOXYANILINO) TEREPHTHALIC ACID POLYMORPHS AND
QUINACRIDONES REALIZED THEREFROM
Abstract
2,5-di(p-methoxyanilino)terephthalic acid crystal types I and II
are made by controlling the pH during the recovery of the oxidized
product of the condensation of dimethylsuccinyl succinate with
p-methoxyaniline. The resulting
2,5-di(p-methoxyanilino)-terephthalic acid can be converted into
2,9-dimethoxyquinacridone or a solid solution thereof having
controlled characteristics.
Inventors: |
Thompson; Brian; (Goose
Creek, SC) ; Rice; Daphne; (Charleston, SC) ;
Tibbs; Tracie; (Charleston, SC) ; Wu; Wengan;
(Mt. Pleasant, SC) ; Britanak; John; (Summerville,
SC) ; Sung; Edward H.; (Cincinnatti, OH) |
Correspondence
Address: |
DICKSTEIN SHAPIRO
1177 AVENUE OF THE AMERICAS (6TH AVENUE)
NEW YORK
NY
10036-2714
US
|
Family ID: |
38529657 |
Appl. No.: |
12/301074 |
Filed: |
May 21, 2007 |
PCT Filed: |
May 21, 2007 |
PCT NO: |
PCT/US07/11958 |
371 Date: |
November 17, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60802379 |
May 22, 2006 |
|
|
|
60802538 |
May 22, 2006 |
|
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Current U.S.
Class: |
428/195.1 ;
106/287.21; 106/31.47; 546/49; 562/452 |
Current CPC
Class: |
C07D 471/04 20130101;
C07C 229/62 20130101; C09D 11/037 20130101; C09D 7/41 20180101;
C09B 67/0027 20130101; Y10T 428/24802 20150115; C09B 48/00
20130101 |
Class at
Publication: |
428/195.1 ;
562/452; 546/49; 106/31.47; 106/287.21 |
International
Class: |
C09D 11/02 20060101
C09D011/02; C07C 229/52 20060101 C07C229/52; C07D 471/04 20060101
C07D471/04; C09D 9/00 20060101 C09D009/00; B32B 3/00 20060101
B32B003/00 |
Claims
1. 2,5-di(p-methoxyanilino)terephthalic acid crystal type II.
2. A method of producing 2,5-di(p-methoxyanilino)terephthalic acid
crystal type II which comprises condensing dimethylsuccinyl
succinate with p-methoxyaniline and adjusting the pH of the
reaction mixture containing the condensation product to
substantially immediately adjust the pH to below about 5.
3. A method of producing 2,5-di(p-methoxyanilino)terephthalic acid
crystal type II which comprises providing a solution of
2,5-di(p-methoxyanilino)terephthalic acid crystal type I having a
basic pH and adjusting the pH of said solution to below about
5.5.
4. A method of making 2,9-dimethoxyquinacridone or a solid solution
thereof which comprises converting
2,5-di(p-methoxyanilino)terephthalic acid to said
2,9-dimethoxyquinacridone or a solid solution thereof, wherein the
2,5-di(p-methoxyanilino)terephthalic acid is
2,5-di(p-methoxyanilino)terephthalic acid crystal type II.
5. 2,9-dimethoxyquinacridone produced by the process of claim
4.
6. 2,9-dimethoxyquinacridone solid solution produced by the process
of claim 4.
7. An ink comprising a colorant and an ink carrier therefor in
which the colorant is the product of the method of claim 4.
8. The ink of claim 7, wherein the colorant is
2,9-dimethoxyquinacridone.
9. The ink of claim 7, wherein the colorant is a solid solution of
2,9-dimethoxyquinacridone.
10. An ink comprising a colorant and an ink carrier therefor in
which the colorant is the product of the method of claim 3.
11. The ink of claim 10, wherein the colorant is
2,9-dimethoxyquinacridone.
12. The ink of claim 10, wherein the colorant is a solid solution
of 2,9-dimethoxyquinacridone.
13. A coating composition comprising a colorant and a coating
composition carrier therefor in which the colorant is the product
of the method of claim 3.
14. The coating composition of claim 13, wherein the colorant is
2,9-dimethoxyquinacridone.
15. The coating composition of claim 13, wherein the colorant is a
solid solution of 2,9-dimethoxyquinacridone.
16. A coating composition comprising a colorant and a coating
composition carrier therefor in which the colorant is the product
of the method of claim 4.
17. The coating composition of claim 16, wherein the colorant is
2,9-dimethoxyquinacridone.
18. The coating composition of claim 16, wherein the colorant is a
solid solution of 2,9-dimethoxyquinacridone.
19. A pigmented article comprising a mass containing a colorant in
which the colorant is the product of the method of claim 4.
20. The pigmented article of claim 19, wherein the colorant is
2,9-dimethoxyquinacridone.
21. The pigmented article of claim 19, wherein the colorant is a
solid solution of 2,9-dimethoxyquinacridone.
22. A pigmented article comprising a mass containing a colorant in
which the colorant is the product of the method of claim 3.
23. The pigmented article of claim 22, wherein the colorant is
2,9-dimethoxyquinacridone.
24. The pigmented article of claim 22, wherein the colorant is a
solid solution of 2,9-dimethoxyquinacridone.
Description
FIELD OF THE INVENTION
[0001] This invention relates to new crystal types of
2,5-di(p-methoxyanilino)terephthalic acid and their use in the
production of 2,9-dimethoxyquinacridone and solid solutions
thereof.
BACKGROUND OF INVENTION
[0002] A conventional method for the production of pigments which
are 2,9-dimethoxyquinacridone or its solid solutions involves the
conversion of 2,5-di(p-methoxyanilino)terephthalic acid to the
desired quinacridone. Color manipulation of the final pigment can
then be achieved by modifying selected post-synthetic quinacridone
manufacture treatments so as to cause changes in the particle size,
particle shape, particle size distribution and/or crystal form of
the final pigment. These steps can entail milling procedures (wet,
dry, with and without milling aids) and heat treatments (with and
without particle growth inhibitors or dispersing aids). It is also
known that the use of fully-formed quinacridone derivatives and/or
their quinacridone intermediate precursors during the synthetic
ring closure procedure to produce the quinacridone itself can be
used as a means to alter the color and physical properties of the
quinacridone. To those skilled in the art, the term pigment
derivative and derivative precursor is well-known. Such derivatives
are usually substituted with either a carbonyl, sulfonyl or other
connecting functionality which is reacted with an acid, amine,
amide, imide, alkyl or alkoxy-containing moiety.
[0003] 2,5-di(p-methoxyanilino)terephthalic acid is a well known
intermediate used in the productions of quinacridones.
Conventionally, this intermediate is prepared by reacting
dimethylsuccinyl succinate and 4-methoxyaniline in a solvent, such
as methanol or a higher alcohol, at elevated temperatures in the
presence of an acid, and possibly under pressure. The resulting
dicondensed material is combined with an oxidizing agent, such as
the sodium salt of m-nitrobenzenesulfonic acid, H.sub.2O.sub.2 or
air, and a base, such as NaOH or KOH, and subsequently heated to an
elevated temperature, possibly under pressure. The resulting
2,5-di(4-methoxyanilino) terephthalic acid or its metal salt is
then diluted with water to obtain a solution. A filtering aid, such
as Celite, may be added to the solution and insolubles removed. The
resulting solution is acidified with an acid, such as HCl or
H.sub.2SO.sub.4 until the product precipitates.
[0004] Polymorphism of the dihydroquinacridone, a quinacridone
precursor, and its impact on the resulting quinacridone is well
known. Polymorphism exhibited by the quinacridones themselves has
also been recognized. For example, P. V. 19's polymorphism is one
of the most widely studied and commercialized examples. The
polymorphism of other quinacridones, such as for example that of P.
R. 122 and P. R. 202, has also been discussed in the literature.
However, there is no evidence in the literature that the
2,5-dianilinoterephthalic quinacridone precursors exhibit
polymorphism. It has been assumed that these precursors have only
one crystal form and, that, because the 2,5-dianilinoterephthalic
acids supposedly dissolve in the ring closing agent, their physical
properties have no impact on the final quinacridone obtained.
[0005] It has been discovered that unlike other
2,5-di(anilino)terephthalic acid derivatives,
2,5-di(p-methoxyanilino)terephthalic acid has two distinctly
different crystal forms, crystal type I and crystal type II, and
that by choosing one of these, the final properties of the
quinacridone or solid solution incorporating the
2,9-dimethoxyquinacridone are changed and/or improved.
SUMMARY OF INVENTION
[0006] In accordance with the present invention, two distinctly
different crystal forms of 2,5-di(p-methoxyanilino)terephthalic
acid, crystal type I and crystal type II, are produced by
controlling the pH recovery conditions to which the oxidized
dicondensed product of dimethylsuccinyl succinate and
4-methoxyaniline is subjected. Crystal type I is characterized by
being brown (powder or wet cake) and has the distinctive X-ray
pattern shown in FIG. 1 with the strongest peak at about d=6.3
angstroms (2.theta.=13.9 via CuK.alpha.). It can be produced by
first adjusting the pH during product recovery to about neutral and
thereafter further reducing the pH to about 4.5 to about 6.5.
Crystal type II is characterized by being violet (powder or wet
cake) and has the distinctive X-ray pattern shown in FIG. 2 with
the strongest peak at about d=16.1 angstroms (2.theta.=5.5 via
CuK.alpha.). It can be produced by adding a
2,5-di(p-methoxyanilino)terephthalic acid solution to a strong acid
such that the final pH is below about 5.0. Alternatively, type I
can be converted into type II.
[0007] Further in accordance with the present invention, the
2,5-di(p-methoxyanilino)-terephthalic acid is converted into a
2,9-dimethoxyquinacridone or a solid solution thereof whose final
properties are changed and/or improved relative to the prior art.
The quinacridone intermediate's crystal form during quinacridone
production, e.g., ring closure, is employed to manipulate the
quinacridone's properties. The quinacridone can be used as a
colorant in inks, coating compositions and masses of materials such
as plastics.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is the X-ray pattern of
2,5-di(p-methoxyanilino)terephthalic acid crystal type I.
[0009] FIG. 2 is the X-ray pattern of
2,5-di(p-methoxyanilino)terephthalic acid crystal type II.
[0010] FIGS. 3A to 3C are mass spectra of
2,5-di(p-methoxyanilino)terephthalic acid crystal type I.
[0011] FIGS. 4A to 4C are mass spectra of
2,5-di(p-methoxyanilino)terephthalic acid crystal type II.
[0012] FIGS. 5A to 5C are mass spectra of
2,5-di(p-methoxyanilino)terephthalic acid crystal type II which had
been converted from type I.
[0013] FIG. 6 is an X-ray spectrum of
2,5-di(p-methoxyanilino)terephthalic acid crystal type II which had
been converted from type I.
[0014] FIG. 7 is X-ray spectra of 2,5-di(p-toluidino)terephthalic
acids made by both processes used to obtain
2,5-di(p-methoxyanilino)terephthalic acid crystal types I &
II.
[0015] FIG. 8 is X-ray spectra of 2,5-di(anilino)terephthalic acids
made by both processes used to obtain
2,5-di(p-methoxyanilino)terephthalic acid crystal types I &
II.
[0016] FIG. 9 is X-ray spectra of
2,5-di(4-chloroanilino)terephthalic acids made by both processes
used to obtain 2,5-di(p-methoxyanilino)terephthalic acid crystal
types I & II.
DETAILED DESCRIPTION OF INVENTION
[0017] The present invention provides two distinctly different
crystal forms of 2,5-di(p-methoxyanilino)terephthalic acid--crystal
type I and crystal type II. These forms can be differentiated by
color (one being brown and one being violet) as well as by X-ray
diffraction pattern. It has also been found that substantially pure
versions of each form, having a purity of at least about 85%, can
be prepared by altering the precipitation method typically used
(i.e., adding a solution of 2,5-di(p-methoxyanilino)terephthalic
acid to a solution of a strong acid to achieve about pH<5.0
versus adjusting the solution of
2,5-di(p-methoxyanilino)terephthalic acid from a high pH to a pH of
about <7.0 with an acid). Hereinafter, the brown crystal form is
designated as the crystal type I while the violet crystal form is
designated as the crystal type II. Crystal type I is the form
previously described in the art.
[0018] One way to produce crystal type I or crystal type II of the
present invention is to control the pH during the recovery of the
oxidized product of the condensation of dimethylsuccinyl succinate
and p-anisidine In the procedure for making the oxidized product,
dimethylsuccinyl succinate can be stirred into a liquid such as an
alcohol to form a slurry and then combined, under stirring, with
p-anisidine. An acid catalyst is added and the mixture is heated to
a sufficient temperature and time to accomplish condensation. After
cooling to room temperature, an oxidizing agent (such as but not
limited to m-nitrobenzene sulfonic acid, sodium salt, hydrogen
peroxide and/or air) may be added. A base is then added and the
mixture heated again to a sufficient temperature and time to
accomplish oxidation. Upon cooling to a temperature below the
reflux temperature of the solvent, the basic reaction slurry is
diluted with water and heated to facilitate solution of the
oxidized product in the water, for example to about 60.degree.
C.
[0019] In order to obtain crystal type I (brown), the solution or
slurry pH is first adjusted from its basic pH to about neutral and
then further adjusted to about 4.5 to about 6.5. To obtain crystal
type II (violet), the solution or slurry is combined with a strong
acid such that the resulting pH is below about 5.0. While not being
bound by theory, it is believed that the time taken to perform the
pH adjustment affects the final crystal type. Crystal type II can
also be made by providing a solution of
2,5-di(p-methoxyanilino)terephthalic acid crystal type I having a
basic pH and combining said solution with an amount of acid
sufficient to make the pH below about 5.0. In all cases, the
resulting slurry may be filtered and washed to a conductivity free
state with deionized water.
[0020] Crystal type I is characterized by being a brown powder or
wet cake. The distinctive X-ray pattern of crystal type I is shown
in FIG. 1. Crystal type II is characterized by being a violet
powder or wet cake, and its distinctive X-ray pattern is shown in
FIG. 2.
[0021] In the past, crystal morphology of quinacridone pigment
precursors has been neglected as a possible way to affect color
properties of the final pigment. The current invention, however,
allows use of the quinacridone intermediate's crystal form during
synthesis (e.g., ring closure) as a method to manipulate the
desired quinacridone's color properties. Thus, it has been found
that the crystal form of the 2,5-di(p-methoxyanilino)terephthalic
acid intermediate used in the synthesis of
2,9-dimethoxyquinacridone and solid solutions thereof, such as but
not limited to those disclosed in U.S. Pat. No. 5,236,498, has an
impact on the coloristic properties of the resulting quinacridone,
as shown in Tables 1 and 2 below.
[0022] Other solid solutions can be made by ring closing the
2,5-di(p-methoxyanilino)-terephthalic acid with other quinacridone
intermediates, such as but not limited to
2,5-di(anilino)terephthalic acid, 2,5-di(toluidino)terephthalic
acid and 2,5-di(chloroanilino)-terephthalic acid. Solid solutions
can also be made by methods known in the art such as, but not
limited to (1) dissolving the crude pigment components in strong
mineral acids, such as sulfuric acid, followed by precipitation in
a liquid in which they are substantially insoluble, (2) ring
closing synthetic intermediates of the quinacridones, before or
after oxidation, in strong acids or high boiling solvents, followed
by precipitation in a liquid in which they are substantially
insoluble, and/or (3) milling the crude quinacridone components
together.
[0023] The crystal type I and II intermediates can be used in any
conventional quinacridone manufacturing process, such as those
described in Industrial Organic Pigments by W. Herbst & K.
Hunger; published by VCH in 2004; pages 452-472, which is
incorporated herein by reference. While both of the type I and type
II crystal forms result in a quinacridone that is very attractive
with respect to color properties, the different crystal types can
be used to impact the resulting quinacridone, which may be the
2,9-dimethoxyquinacridone alone or any solid solution in which it
is a part, for example but not limited to those solid solutions
disclosed in U.S. Pat. No. 5,236,498 (incorporated herein by
reference). It has also been surprisingly found that the crystal
type of 2,5-di(p-methoxyanilino)-terephthalic acid can affect the
resulting quinacridone coloristically by altering shade hues and
chromas. The intermediate's crystal type may also impact the
physical properties of the resulting 2,9-dimethoxyquinacridone or
its solid solutions in terms of improving surface area, particle
size, size distribution, weatherfastness, lightfastness and
masstone.
[0024] Of course, the crystal form of the intermediate is not the
only thing that impacts the color properties of the quinacridone or
solid solution. The ring closing conditions chosen may also impact
the effect observed on the quinacridone color and physical
properties discussed above as they relate to the intermediate's
crystal form. In fact, ring closing conditions can be chosen such
that the trends observed between the brown and violet crystal forms
of 2,5-di(p-methoxyanilino)terephthalic acid can be reversed and/or
neutralized, if desired.
[0025] The resulting pigment or solid solution pigment of the
invention can undergo post treatment by any of the methods known to
those skilled in the art to further manipulate and/or improve
color, physical and lightfastness properties.
[0026] The invention gives the pigment manufacturer a new and
valuable tool to manipulate final pigment properties. Additionally,
the knowledge of these two crystal forms and their impact on the
final pigment's color properties allows the pigment manufacturer
more control over the process. It is always advantageous to produce
a known entity in order to control the outcome of subsequent steps.
One of the advantages of this invention over prior art is that
being able to produce essentially pure versions of each crystal
form gives the manufacturer more control over the outcome of the
ring closure. Previously, when the 2,5-di(p-methoxyanilino)
terephthalic acid was ring closed, no attention was paid to the
purity of the crystal form because it was believed that the
2,5-dianilinoterephthalic acids dissolved in the polyphosphoric
acid (or other appropriate ring closure or dehydrating agent). The
physical properties of the intermediates themselves were also
thought to have no impact of relevance on the final product.
However, as described above, It has thus been discovered that in
fact the 2,5-di(p-methoxyanilino)terephthalic acid is indeed
polymorphic, whereas other commonly used quinacridone intermediates
such as 2,5-di(aniline)-terephthalic acid (FIG. 8),
2,5-di(toluidino)-terephthalic acid (FIG. 7) and
2,5-di(chloroanilino)-terephthalic acid (FIG. 9) are not
polymorphic. Further, it has been found that the polymorphism of
the 2,5-di(p-methoxyanilino)terephthalic acid impacts the
coloristic properties of the quinacridones and solid solutions in
which it is used as the precursor or in combination with other
quinacridone precursors.
[0027] In order to further illustrate the present invention,
various non-limiting examples are set forth below, in which (as
throughout this specification and claims) all parts and percentages
are by weight and all temperatures in degrees Centigrade, unless
otherwise indicated.
EXAMPLE 1 (CRYSTAL TYPE I)
[0028] To a pressure reactor were charged 489.8 g of methanol. With
agitation, 50 g of dimethylsuccinyl succinate were charged and
stirred for .about.10 minutes. To the stirring slurry were added
56.7 g of p-anisidine. After stirring for .about.15 minutes, 0.8 g
of 96% H.sub.2SO.sub.4 were added dropwise. The reactor was sealed,
heated to 95-100.degree. C. and held at this temperature for
approximately 5 hours. After cooling to 40-50.degree. C., the
reactor was opened and with agitation, 55.6 g of
m-nitrobenzenesulfonic acid, sodium salt, were added. After
stirring for .about.5 minutes, 127.8 g of 45% KOH were charged over
a 15 minute period. The reactor was sealed, heated to 90-95.degree.
C. and held at this temperature for approximately 4 hours. Upon
cooling to 40-50.degree. C., the reaction slurry was transferred to
a container containing 800 g of H.sub.2O. Once the transfer was
complete, an additional 275 g of H.sub.2O were added and with
stirring, the solution was heated to 30-40.degree. C. The pH was
then adjusted from 13 to 7.5-7.0 with 40.0 g of 96%
H.sub.2SO.sub.4. After stirring for 5 minutes, the pH was further
adjusted to 5.0-5.5 with 12.8 g of 96% H.sub.2SO.sub.4. After
stirring for 15 minutes at 30-40.degree. C., the resulting brown
slurry was filtered and washed until conductivity free with
deionized water. The presscake was dried to obtain approximately 85
g of brown powder. When evaluated by HPLC (Waters system equipped
with a 996 PDA detector), the purity was 96.3%
2,5-di(p-methoxyanilino)-terephthalic acid. The sample was also
evaluated by LC-MS (Agilent HP1100 LC/MS) to verify the major
component as 2,5-di(p-methoxyanilino)terephthalic acid by mass
spectrum. The x-ray diffraction of the dry product is shown in FIG.
1 and the mass spectra are shown in FIGS. 3A to 3C. Elemental
analysis of the sample gave the following molecular composition:
C=64.77%; H=5.05%; N=6.91%; O=21.94%.
[0029] The X-ray data for crystal type I, with very weak
diffraction peaks omitted for simplification, are:
TABLE-US-00001 d (in angstroms) Intensity 18.0 Weak 10.4 Medium 9.4
Strong 8.6 Weak 6.3 Very strong 5.9 Medium 5.4 Weak 5.2 Medium 4.7
Weak 4.24 Weak 4.18 Medium 3.9 Strong 3.8 Weak 3.6 Weak 3.4 Weak
3.2 Weak 3.1 Medium 3.0 Medium
EXAMPLE 2 (CRYSTAL TYPE II)
[0030] To a pressure reactor were charged 489.8 g of methanol. With
agitation, 50 g of dimethylsuccinyl succinate were charged and
stirred for .about.10 minutes. To the stirring slurry were added
56.7 g of p-anisidine. After stirring for .about.15 minutes, 0.8 g
of 96% H.sub.2SO.sub.4 were added dropwise. The reactor was sealed,
heated to 95-100.degree. C. and held at this temperature for
approximately 5 hours. After cooling to 40-50.degree. C., the
reactor was opened and with agitation, 55.6 g of
m-nitrobenzenesulfonic acid, sodium salt, were added. After
stirring for .about.5 minutes, 127.8 g of 45% KOH were charged over
a 15 minute period. The reactor was sealed, heated at 90-95.degree.
C. and held at this temperature for approximately 4 hours. Upon
cooling to 55-65.degree. C., the reaction slurry was transferred to
a container using water to a total volume of 1200 mL. The solution
was held 15 minutes at 55-65.degree. C., then transferred over
45-60 minutes, via a pump, to a vessel containing 1344 g of a 3.6%
HCl solution. The resulting violet slurry was stirred for 15
minutes at 40-50.degree. C., at which point it had a pH of 1.2. The
pH was adjusted with 15 g of 50% NaOH to a pH of 2-2.5. After
stirring an additional 20 minutes, the slurry was filtered and the
violet presscake was washed conductivity free with water. The
presscake was dried to obtain 79.7 g of violet powder. When
evaluated by HPLC, the purity was 97%
2,5-di(p-methoxyanilino)terephthalic acid. The x-ray diffraction
pattern of the violet product is shown in FIG. 2. The sample was
also evaluated by LC-MS to confirm that the major compound was
indeed 2,5-di(p-methoxyanilino)terephthalic acid and FIGS. 4A to 4C
show the mass spectra. Elemental analysis of the sample gave the
following molecular composition: C=64.76%; H=5.10%; N=6.73%;
O=22.63%.
[0031] The X-ray data for crystal type II, with very weak
diffraction peaks omitted for simplification, are
TABLE-US-00002 d (in angstroms) Intensity 24.3 Medium 16.1 Very
Strong 8.0 Medium 6.8 Weak 6.3 Strong 5.7 Medium 5.3 Weak 4.6 Weak
4.5 Medium 4.3 Medium 4.1 Medium 4.0 Medium 3.8 Weak 3.6 Weak 3.3
Medium 3.2 Medium
[0032] Comparison of the X-ray diffraction pattern (FIG. 2) with
the X-ray diffraction pattern of
2,5-di(p-methoxyanilino)terephthalic acid produced by Example 1
(FIG. 1) shows these two are distinct.
EXAMPLE 3
[0033] A portion of the brown product of Example 1 (50 g) was
dissolved in water having a basic pH (955 g water and 75.2 g 45%
KOH). The resulting solution was stirred for 55-65.degree. C. for
60 minutes and then allowed to cool to 35-40.degree. C. The pH was
then adjusted from 12.8 to 5.3 with 31.7 g 96% H.sub.2SO.sub.4. The
resulting violet slurry was stirred for 60 minutes at 35-40.degree.
C., at which time it was filtered and the resulting presscake
washed with water until conductivity free (<120% of incoming
wash water). The washed presscake was then dried in an oven to
obtain 43 g of violet powder. When evaluated by HPLC, the purity
profile was 93.3% 2,5-di(p-methoxyanilino)terephthalic acid.
Evaluation by LC-MS confirmed that the major component was indeed
2,5-di(p-methoxyanilino)terephthalic acid. The mass spectra (FIGS.
5A to 5C) and X-ray diffraction pattern (FIG. 6) confirms that the
violet type intermediate was obtained.
EXAMPLE 4 (COMPARATIVE)
[0034] To a pressure reactor were charged 300.4 g of methanol, 33.9
g dimethylsuccinyl succinate, 33.9 g of p-toluidine and 0.4 g of
96% H.sub.2SO.sub.4. The reactor was sealed and heated to
92-96.degree. C. over approximately 1.5 hours and then held
approximately for 5 hours at 92-96.degree. C. After cooling to room
temperature, the reactor was opened and 26.2 g of
m-nitrobenzenesulfonic acid, sodium salt, were added along with
60.5 g of 50% NaOH and 24 g water. The reactor was sealed and
heated at 90-94.degree. C. over 1.5 hours and then held
approximately 4 hours at that temperature. Upon cooling to room
temperature, the reaction slurry was transferred to a container and
the total volume adjusted to 1 liter with water. The resulting
slurry was allowed to stir approximately 30 minutes at
35-45.degree. C. The pH was then adjusted from 12 to 5.2 with
approximately 96 g of 25% H.sub.2SO.sub.4. The resulting violet
slurry was allowed to stir for 1 hour at 35-45.degree. C., at which
point, it had a pH of 5.5. The slurry was filtered and washed with
deionized water to 20 microSiemens. The resulting presscake was
dried to obtain approximately 53 g of product which, when evaluated
by HPLC, had a purity profile of >90%
2,5-di(p-toluidino)terephthalic acid.
EXAMPLE 5 (COMPARATIVE)
[0035] To a pressure reactor were charged 300.4 g of methanol, 33.9
g dimethylsuccinyl succinate, 33.9 g of p-toluidine and 0.4 g of
96% H.sub.2SO.sub.4. The reactor was sealed and heated to
92-96.degree. C. over approximately 1.5 hours and then held for
approximately 5 hours at 92-96.degree. C. After cooling to room
temperature, the reactor was opened and 26.2 g of
m-nitrobenzenesulfonic acid, sodium salt, were added together with
60.5 g of 50% NaOH and 28 g water. The reactor was sealed and the
reaction mixture heated at 90-94.degree. C. over 1.5 hours and then
held 4 hours at 90-94.degree. C. Upon cooling to room temperature,
the reaction slurry was transferred to a container and the total
volume adjusted to 1 liter with water. The solution was held about
30 minutes at 40-50.degree. C. and pH=12. The solution was then
transferred, via a pump, to a vessel containing 1008 g of 5.5%
H.sub.2SO.sub.4 stirring vigorously. The transfer took
approximately 1 hour and produced a violet slurry similar to
Example 4. The slurry was allowed to stir approximately 1 hour at
40-50.degree. C., pH=1.5. The slurry, having a pH of 1.7, was
filtered and washed with deionized water to 18 microSiemens. The
resulting presscake was dried to obtain approximately 53 g of
product which, when evaluated by HPLC, had a purity profile of
>90% 2,5-di(p-toluidino)terephthalic acid. The X-ray diffraction
patterns of the products of Example 4 and Example 5 were
superimposed, as shown in FIG. 7, and were the same indicating they
both had the same crystal form, i.e., there was no
polymorphism.
EXAMPLE 6 (COMPARATIVE)
[0036] To a pressure reactor were charged 226 g of methanol, 36.0 g
dimethylsuccinyl succinate, 35.3 g aniline and 13.2 g glacial
acetic acid. The reactor was sealed and heated to 104.degree. C.
over approximately 1.5 hours and then held approximately for 5
hours at 104.degree. C. After cooling to room temperature, the
reactor was opened and 27 g of m-nitrobenzenesulfonic acid, sodium
salt, 74 g of 50% NaOH and 25 g water were added. The reactor was
sealed and the reaction heated at 113.degree. C. over 1.5 hours and
then held for approximately 4 hours at 113.degree. C. Upon cooling
to 63.degree. C., the reaction slurry was transferred to a
container and the total volume adjusted to 1 liter with water. The
resulting solution was heated to 40.degree. C. and held at
40.degree. C. for 1 hour. The pH was then adjusted from 12.2 to 5.3
with 145.5 g 25% H.sub.2SO.sub.4. The resulting violet slurry was
allowed to stir 1 hour at 40.degree. C. The pH prior to filtration
was 5.4. The slurry was filtered and washed with deionized water to
14 microSiemens. The resulting presscake was dried to obtain
approximately 52 g of product. When evaluated by HPLC, the purity
profile was >90% 2,5-dianilinoterephthalic acid.
EXAMPLE 7 (COMPARATIVE)
[0037] To a pressure reactor were charged 226 g of methanol, 36.0 g
dimethylsuccinyl succinate, 35.3 g aniline and 13.2 g glacial
acetic acid. The reactor was sealed and heated to 104.degree. C.
over approximately 1.5 hours and then held for approximately 5
hours at 104.degree. C. After cooling to room temperature, the
reactor was opened and 27 g of m-nitrobenzenesulfonic acid, sodium
salt, 74 g of 50% NaOH and 23 g water were added. The reactor was
sealed and the reaction heated at 113.degree. C. over 1.5 hours and
then held for approximately 4 hours at 113.degree. C. Upon cooling
to 53.degree. C., the reaction slurry was transferred to a
container and the total volume adjusted to 1 liter to obtain a
solution that was held 1 hour at 50.degree. C., pH=12. The solution
was then transferred via a pump to a container with 1072 g of 5%
H.sub.2SO.sub.4 stirring vigorously. The transfer took 1 hour,
giving a violet slurry similar to Example 6. The slurry was allowed
to stir 1 hour at 40.degree. C., pH=2.4. The pH prior to filtration
was 2.4. The slurry was filtered and washed with deionized water to
16 microSiemens. The resulting presscake was dried to obtain
approximately 51.9 g of product. When evaluated by HPLC, the purity
profile was >90% 2,5-dianilinoterephthalic acid. A superposed
X-ray diffraction pattern comparison of the products of Example 7
and Example 6 revealed they had the same crystal form, shown in
FIG. 8, i.e., there was no polymorphism. When evaluated by LC-MS,
the purity was 95.8% 2,5-dianilinoterephthalic acid.
EXAMPLE 8 (COMPARATIVE)
[0038] To a pressure reactor were charged 303 g of methanol, 30.3 g
dimethylsuccinyl succinate, 37.9 g 4-chloroaniline and 0.6 g 96%
H.sub.2SO.sub.4. The reactor was sealed and heated to 97.degree. C.
over approximately 1.5 hours and then held for approximately 5
hours at 97.degree. C. After cooling to room temperature, the
reactor was opened and 33.4 g of m-nitrobenzenesulfonic acid,
sodium salt, were added together with 77 g of 50% NaOH and 14 g
methanol. The reactor was sealed and the reaction heated at
93.degree. C. over 1.5 hours and then held for approximately 4
hours at 93.degree. C. Upon cooling to 34.degree. C., the reaction
slurry was transferred to a container and the total volume adjusted
to 1600 mL with water. The resulting solution was heated to
40.degree. C. and the pH was then adjusted from 12.4 to 5.3 with
146.4 g 20% H.sub.2SO.sub.4 over 1 hour. The resulting red slurry
was allowed to stir 1 hour at 40.degree. C. The pH prior to
filtration was 5.4. The slurry was filtered and washed with
deionized water to 45 microSiemens. The resulting presscake was
dried to obtain approximately 52.6 g of product. When evaluated by
LC-MS, the purity profile was 95.8%
2,5-di(4-chloroanilino)terephthalic acid.
EXAMPLE 9 (COMPARATIVE)
[0039] To a pressure reactor were charged 301.8 g of methanol, 30.0
g dimethylsuccinyl succinate, 37.3 g 4-chloroaniline and 0.6 g 96%
H.sub.2SO.sub.4. The reactor was sealed and heated to 97.degree. C.
over approximately 1.5 hours and then held for approximately 5
hours at 97.degree. C. After cooling to room temperature, the
reactor was opened and 33.5 g of m-nitrobenzenesulfonic acid,
sodium salt, were added together with 77 g of 50% NaOH and 14.8 g
methanol. The reactor was sealed and the reaction heated at
93.degree. C. over 1.5 hours and then held approximately 4 hours at
93.degree. C. Upon cooling to room temperature, the reaction slurry
was transferred to a container and the total volume adjusted to
1600 mL to obtain a solution that was held 15 minutes at 50.degree.
C., pH=11.8. The solution was then transferred via a pump to a
container with 806 g of 5.5% H.sub.2SO.sub.4 stirring vigorously.
The transfer took 1.5 hours, giving a violet slurry. The slurry was
allowed to stir 1 hour at 40.degree. C. and a pH of 2. Within 15
minutes, the violet slurry had turned red. The slurry was filtered
and washed with deionized water to 16 microSiemens. The resulting
presscake was dried to obtain approximately 51.5 g of product. When
evaluated by LC-MS, the purity profile was 93.7%
2,5-dianilinoterephthalic acid. A superposed X-ray diffraction
pattern comparison of the products of Example 9 and Example 8 (FIG.
9) revealed the same crystal form, i.e., there was no
polymorphism.
EXAMPLE 10 (QUINACRIDONE PIGMENT SOLID SOLUTION FROM CRYSTAL TYPE
I)
[0040] To a container were charged 360.1 g of 117% polyphosphoric
acid and it was then heated to 85.degree. C. with agitation. At
85-95.degree. C., 15.2 g of 2,5-di(4-chloroanilino)terephthalic
acid were added over 30-60 minutes. After the
2,5-di(4-chloroanilino)terephthalic acid had dissolved, 45 g of
2,5-di(4-methoxyanilino) terephthalic acid type I prepared
according to Example 1 were added over .about.90 minutes while
maintaining the temperature <115.degree. C. The reaction mixture
was allowed to stir 5 hours at 110-115.degree. C. The reaction
mixture was then cooled to approximately 90.degree. C. and poured
slowly into a container with 900.6 g vigorously stirring methanol
over .about.15 minutes. The methanol temperature during the
drowning step was maintained at <35.degree. C. via an ice-water
bath under the container. The violet methanol-pigment slurry was
allowed to stir 1 hour at room temperature and then heated to
reflux (68-72.degree. C.). The slurry was then held 1 hour at
reflux. The slurry was allowed to cool to T<65.degree. C. and
then poured into a container containing 1350 g of water. The
resulting water/methanol/pigment slurry was held 1 hour at
60.degree. C. and then filtered. The resulting presscake was washed
with water to a pH of 3.5. Approximately 135 g presscake at
approximately 35.4% solids was obtained, resulting in approximately
48 g solids. From this presscake, approximately 67.8 g presscake
(.about.24 g dry pigment) were reslurried in a quantity of water
and methanol sufficient to realize a total of 170 g water and 189 g
methanol. The slurry pH was adjusted to approximately 7.3 with
dilute NaOH, and then transferred to a Parr pressure reactor and
1.5 g 50% NaOH added. The reactor was sealed and held 6 hours at
120-125.degree. C. After allowing the reaction mixture to cool to
room temperature, the slurry was transferred to a beaker. At
40-45.degree. C. and a pH of 11, 2.0 g Dresinate X (manufactured by
Hercules) dissolved in water were added to the above stirring
slurry. After 30 minutes at 40-45.degree. C., 4 g of calcium
chloride dehydrate, dissolved in water, were added to the slurry.
After adjusting the total volume to 1 L with water and stirring
approximately 15 minutes at 40-45.degree. C., the pH was adjusted
to approximately 4.3 with 75% phosphoric acid. After stirring 1
hour at 40-45.degree. C., the slurry was filtered and the resulting
presscake washed with water to a conductivity free condition. The
presscake was dried to obtain approximately 25.2 g of violet
pigment powder and the crystal form was the same as that of the 25%
dichloroquinacridone/75% dimethoxyquinacridone reported in U.S.
Pat. No. 5,236,498. The color properties of this pigment, when
evaluated in a solventborne paint, are shown in Tables 1 and 2.
EXAMPLE 11 (QUINACRIDONE PIGMENT SOLID SOLUTION FROM CRYSTAL TYPE
II)
[0041] Three hundred sixty grams of 117% polyphosphoric acid were
charged into a container and heated to 85.degree. C. with
agitation. At 85-95.degree. C., 15.1 g of
2,5-di(4-chloroanilino)terephthalic acid were added over 30-60
minutes, and after the 2,5-di(4-chloroanilino)terephthalic acid had
dissolved, 45 g of 2,5-di(4-methoxyanilino) terephthalic acid type
2 prepared according to Example 2 were added over .about.90 minutes
while maintaining the temperature <115.degree. C. The reaction
mixture was allowed to stir for 5 hours at 110-115.degree. C., then
cooled to approximately 90.degree. C. and poured slowly into a
container containing 900 g of vigorously stirring methanol over
.about.15 minutes. The methanol temperature during the drowning was
maintained at <35.degree. C. via an ice-water bath under the
container. The violet methanol-pigment slurry was allowed to stir 1
hour at room temperature and then heated to reflux (68-72.degree.
C.) where the slurry was held for 1 hour. The slurry was allowed to
cool to T<65.degree. C. and then poured into a container with
1350 g of water. The resulting water/methanol/pigment slurry was
held 1 hour at 60.degree. C. and then filtered. The resulting
presscake was washed with water to a pH 3.2. Approximately 274.4 g
of presscake were obtained at approximately 19.94% solids,
resulting in approximately 54.7 g of solids. From this presscake,
126 g presscake (approximately 25 g dry basis pigment) were
reslurried in a quantity of water and methanol sufficient to
achieve a total of 150 g water and 150 g methanol. The slurry pH
was adjusted approximately 7.4 with dilute NaOH, and then
transferred to a 600-mL Parr pressure reactor and 1.5 g 50% NaOH
added. The reactor was sealed and held 6 h at 120-125.degree. C.
After allowing the reaction to cool to room temperature, the slurry
was transferred to a 1500-mL beaker. At 40-45.degree. C. and pH of
11.1, 2.0 g Dresinate X dissolved in water were added to the
stirring slurry, followed by, after 30 minutes, 4 g of calcium
chloride dehydrate, dissolved in water. After adjusting the total
volume to 1 L with water and stirring for approximately 15 minutes
at 40-45.degree. C., the pH was adjusted to approximately 4.3 with
75% phosphoric acid. After stirring 1 hour at 40-45.degree. C., the
slurry was filtered and the resulting presscake washed with water
to a conductivity free condition. The presscake was dried to obtain
approximately 24 g of violet pigment powder and the crystal form
was the same as that of the 25% dichloroquinacridone/75%
dimethoxyquinacridone reported in U.S. Pat. No. 5,236,498. The
color properties of this pigment, when evaluated in a solventborne
paint, are shown in Tables 1 and 2.
EXAMPLE 12
Paint Evaluation
[0042] The pigments of Examples 10 and 11 and a pigment produced
according to U.S. Pat. No. 5,236,498 (as a standard) were combined
at the same concentration in the same solventborne paint and then
evaluated for tint shade and metallic shade. The results relative
to the standard are shown in Tables 1 and 2. The data shows that
the pigment of Example 10 is distinctly bluer in hue than the
pigment produced in Example 11.
TABLE-US-00003 TABLE 1 Tint shade Pigment DL Da Db DC DH DE Example
10 0.22 -2.19 0.49 -1.62 -1.55 2.26 Example 11 0.16 -1.83 1.05
-1.90 -0.92 2.12
TABLE-US-00004 TABLE 2 Metallic shade Pigment DL Da Db DC DH DE
Example 10 -1.24 -0.23 -1.26 -0.11 -1.28 1.78 Example 11 -0.61
-0.59 -0.13 -0.58 -0.17 0.86
EXAMPLE 13 (QUINACRIDONE PIGMENT FROM CRYSTAL TYPE I)
[0043] Charged to a container were 360 g of 117% polyphosphoric
acid and they were heated to 85.degree. C. with agitation. At
85-105.degree. C., 60 g of 2,5-di(4-methoxyanilino) terephthalic
acid type I prepared according to Example 1 were added over 60-90
minutes and the reaction mixture was allowed to stir 5 hours at
110-115.degree. C. The reaction mixture was then cooled to
approximately 90-95.degree. C. and poured slowly into a container
containing 900 g of vigorously stirring methanol over .about.15
minutes. The methanol temperature during the drowning was
maintained at <35.degree. C. via an ice-water bath under the
round bottom flask. The violet methanol-pigment slurry was allowed
to stir 1 hour at room temperature and then heated to reflux
(68-72.degree. C.) where it was then held for 1 hour. The slurry
was allowed to cool to <65.degree. C. and then poured into a
container with 1350 g of water. The resulting
water/methanol/pigment slurry was held for 3 hours at 60.degree. C.
and then filtered. The resulting presscake was washed with water to
a pH of 2.9. Approximately 214.3 g presscake were obtained at
approximately 26.42% solids, resulting in approximately 56.6 g
solids. Approximately, 25 g dry basis pigment from the presscake
were reslurried in water and methanol to a total of 150 g water and
150 g methanol. The slurry pH was adjusted approximately 7 with
dilute NaOH. The slurry was then transferred to a Parr pressure
reactor and 1.5 g 50% NaOH added. The reactor was sealed and held 6
hours at 120-125.degree. C. After allowing the reaction mixture to
cool to room temperature, the slurry was transferred to a beaker.
At 40-45.degree. C., 2.0 g Dresinate X dissolved in water were
added to the stirring slurry. After 30 minutes at 40-45.degree. C.,
4 g of calcium chloride dehydrate, dissolved in water, were added
to the slurry. After adjusting the total volume to 1 L with water
and stirring for approximately 15 minutes at 40-45.degree. C., the
pH was adjusted to 4-4.5 with 75% phosphoric acid. After stirring 1
hour at 40-45.degree. C., the slurry was filtered and the resulting
presscake washed with water to conductivity free. The presscake was
dried to obtain approximately 24 g of violet pigment powder.
EXAMPLE 14 (QUINACRIDONE PIGMENT FROM CRYSTAL TYPE II)
[0044] Three hundred sixty grams of 117% polyphosphoric acid were
placed in a container and heated to 85.degree. C. with agitation.
At 85-107.degree. C., 60 g of 2,5-di(4-methoxyanilino)terephthalic
acid type II prepared according to Example 2 were added over 60-90
minutes, and the reaction mixture allowed to stir for 5 hours at
110-115.degree. C. The reaction mixture was then cooled to
approximately 90-95.degree. C. and poured slowly into container
which contained 900 g vigorously stirring methanol over .about.15
minutes. The methanol temperature during the drowning was
maintained at <35.degree. C. via an ice-water bath under the
container. The violet methanol-pigment slurry was allowed to stir 1
hour at room temperature and then heated to reflux (68-72.degree.
C.) where it was held 1 hour, followed by being allowed to cool to
T<65.degree. C. and then poured into a container with 1350 g of
water. The resulting water/methanol/pigment slurry was held 3 hours
at 60.degree. C. and then filtered. The resulting presscake was
washed with water to a pH of 2.9. Approximately 128.3 g presscake
was obtained at approximately 45.75% solids, resulting in
approximately 58.7 g solids being obtained. Approximately 25 g dry
basis pigment from the presscake were reslurried in water and
methanol to a total of 150 g water and 150 g methanol, and the
slurry pH was adjusted approximately 7 with dilute NaOH. The slurry
was then transferred to a Parr pressure reactor and 1.5 g 50% NaOH
added. The reactor was sealed and held for 6 h at 120-125.degree.
C. After allowing the reaction to cool to room temperature, the
slurry was transferred to another container. At 40-45.degree. C.,
2.0 g Dresinate X dissolved in water were added to the stirring
slurry. After 30 minutes at 40-45.degree. C., 4 g of calcium
chloride, dissolved in water, were added to the slurry, and after
adjusting the total volume to 1 L with water and stirring for
approximately 15 minutes at 40-45.degree. C., the pH was adjusted
to 4-4.5 with 75% phosphoric acid. After stirring 1 hour at
40-45.degree. C., the slurry was filtered and the resulting
presscake washed with water to a conductivity free condition. The
presscake was dried to obtain approximately 24 g of violet pigment
powder.
[0045] Various changes and modifications can be made to the
preferred embodiments described above without departing from the
spirit and scope of the invention. The embodiments set forth were
intended to be illustrative only and were not intended to limit the
invention.
* * * * *