Document aJqJdEe4eB62v8ojL44naK9Za
E. I. DU PONT DE NEMOURS & COMPANY 256 VANDERPOOL STREET NEWARK, NEW JERSEY
Serial No.KN-68-5
Copy No.
RETURN TO JACKSON LABORATORY
FILE ROOM
NEWARK PLANT PIGMENT COLOR RESEARCH REPORT
HEAT RESISTANT QUINACRIDONE PIGMENT (PART I)
Period Covered March, 1966 to August, 1967 (Part Time)
FILE. 223.91 DATE: 9/3/68
N33721
NJ 0344
KN-68-5
Copy No
1, Numerical File
2. Research Office Pile, Newark 223.91
3* Newark Library Pile 223.91 4. M. Hunt/E. Gonick, Pigts., Wilm.
5. w. s. Struve/A.A.Brizzolara
6. P.P.Ehrlcfc/H. H. Gyorgy/B. H. Perkins/Newark Library 7. P.J. Monahan, Newark Vital Records
8. N. G. Fisher, Central Research, Wilmington 9. 0.R.Aldridge, Newark 10. R. H.Wetzel/J.W.Minnich/J.P.Maurer/Newport Pile
11. Extra 12. Extra 13. Extra 14. Extra
NEWARK PLANT
PIGMENT COLOR RESEARCH REPORT
SUBJECT: HEAT RESISTANT QUINACRIDONE PIGMENT (PART I)
PERIOD COVERED: MARCH, 1966 to AUGUST, 1967 (Part time)
> (k (i'Jt. _1.
SUBMITTED BY: G. R, ALDRIDGE
Date Submitted: 7/50/68
ABSTRACT
Of fifteen substituted quinacridones tested in polystyrene plastic,2,9-dicarboxyquinacridone exhibited the best heat (color) stability. 2,9-Dicarboxyquinacridone also exhibited excellent heat stability in "Zytel" nylon, a very rigorous system for testing heat stability.
TABLE OP CONTENTS
I. OBJECT OF INVESTIGATION II. PERIOD COVERED BY REPORT III. INTRODUCTION IV. SUMMARY AND CONCLUSIONS
V. PATENT STATUS VI. DISCUSSION VII. EXPERIMENTAL VIII. SUGGESTIONS FOR ADDITIONAL WORK IX. NOTEBOOK REFERENCES
ag 1 1 1 I 2 3 4 8
DUP050028301
I. OBJECT OP INVESTIGATION
To find a heat stable red pigment for use in high tempera ture plastics applications (Part i) and to develop an economically
feasible process for its manufacture (Part IX).
XI. PERIOD COVERED BY REPORT
March, 1966 to August, 1967 (Part Time)
III. INTRODUCTION
Quinacridone Is a relatively insoluble red pigment which is suitable for use in some plastics but not all, Quinacridone in a polyamide system such as "Zytel" nylon is sufficiently soluble at higher temperatures so that the color in low concentrations is a fluorescent yellow characteristic of quinacridone in solution. This color is also shown by quinacridone solutions in dimethy1-
formamide and 1-chloronaphthalene.
Prom a consideration of the relative solubilities of quin acridone (.08 g/l) and 2,9-dime thylquinacridone (.027 g/l) in a model solvent such as boiling 1-chloronaphthalene, and the fact that the latter quinacridone shows better heat or color stability
than the former in polystyrene plastic, it follows that the heatstability of such chemically inert pigments is determined by their solubility in the plastic. Specifically, pigments soluble in the plastic will show poor heat (color) stability and pigments
insoluble in the plastic will show good heat stability.
The solubility of 2,9-dicarboxyquinacridone (I) in boiling 1-chloronaphthalene was found to be very low (< 0.01 g/l). The evaluation of I and other substituted quinacridones in poly styrene and "Zytel" nylon plastic showed I to have relatively outstanding heat stability.
IV. SUMMARY AND CONCLUSIONS
The following table lists the results of heat stability tests on fifteen substituted quinacridones in polystyrene plastic.
Substituent
Color Difference (4008P. vs. 600F. ) UV Fluorescence
2.9- diearboxy
2.9- dicarboxyamido 2.9- dicarboethoxy
2.9- dicyano 2.9- dichloro 2.9- dlbromo 2.9- difluoro
little
" "
" " " "
no
H ii ii
DUP050028302
-2-
Substituent
Color Difference (400F vs, 600ff, )
UV Fluorescence
2.9- dimethyl
2.9- dimethoxy
2.3.9.10- tetrachloro
2.4.9.11- tetrachloro
4.11-
dibromo
4.11- dimethoxy
4.11- dichloro
4.11- difluoro
l!little
cit onsiderable ii n ii
**s
it
ii
ii
ii
ii
ii
All of the 4,11- disubstituted quinacridones were poor in heat stability* All the 2,9- substituted quinacridones were good
in heat stability except for the one which was also substituted in the 4,11- positions, i.e*, the 2,4,9,11-tetrachloro isomer. The remarkable difference in heat stability between the 2,9- and 4.11- substituted quin&pridones is not surprising in view of the appreciably lower solubility of the former versus the latter in l-chloronaphthalene.
Examination cf the 600F. chips under ultraviolet light re veals that I is essentially insoluble whereas all the other substituted quinacridones are soluble to some extent.
That the heat stability of I is unique can be Seen from the following table which lists the results of heat stability tests run by the Plastics Department in Parkersburg, West Virginia, on five substituted quinacridones in "Zytel" nylon. The latter is regarded as a very rigorous system for testing heat stability.
QA Substituent
Color
UV Fluorescence
2.9-dicarboxy 2.9-dicarboxyamido
2.9-difluoro
2.9-dichloro 2.9-dimethyi
Violet
n
Yellow
it
Violet-weak Green Yellow
ii
it
Of the quinacridones tested in this polyamide system at
540F,, only the diacid and diamide retained their red color, and the stronger fluorescence of the diamide versus the diacid suggests that it is the more soluble of the two.
V. PATENT STATUS
CP-75, Polar Quinacridones, was submitted to the Patent Liaison Group at Newport for the preparation of a composition of matter case on 2,9-dicarboxyquinacridone. A use case on this product may also be advisable.
DUP050028303
3
VI. DISCUSSION
The extreme insolubility of 2,9-dicarboxyquinacridone (I) In organic solvents and in plastics systems is believed to be due to intermolecular hydrogen bonding between the carboxy groups in the 2- and 9- positions as follows:
This presumption is supported by the well-known existence of carboxylic acid dimers and the fact that the unique insolubility of I is associated with the carboxyl groups in the 2- and 9positions. 4,11-Dicarboxyquinacrldone would certainly be more soluble than I and, probably, more soluble than the unsubstituted quinacridone because the intramolecular hydrogen bonding between the carboxyl carbonyl and amino groups would reduce the intermolecular hydrogen bonding between the acrldone carbonyl and amino groups. One can only speculate about the properties of 1,8- and 3,10-dicarboxyquinacridones. A x,xi-dloarboxyquinacridone from the reaction of quinacridone, oxalyl chloride, and aluminum chloride in nitrobenzene showed considerable fluorescence in polystyrene indicating the presence of dicarboxyquinacridone isomers other than the 2,9-.
The lightfastness (12 months - Florida exposure, 5 South) of I versus "Monastral" Red (RT-790-D) and "Monastral" Violet (RT-795-D) is summarized in the following table.
Series 66479
Series 66481
Al/Toner
" Tint
10/90
75/25 _sn
Al/Toner 10/90 50/50
Tint *5795
I (crude) I (milled) RT-790-D
RT-795-D
4f
3f 4d
4d
0 If
0 If 4f 4f 5 4f.
m mm
4f 3f 2f 7f 6f 6f 8d 6f 6f
The reason for the inferior lightfastness of I to that of unsubstituted quinacridone is a matter of speculation. The
failure of I in raetalllcs (aluminum-containing systems) and tint may be due to the interaction of the acidic carboxyl group with aluminum and titanium dioxide, respectively. Another
possible explanation is that the average particle size of I
DUPO 50028304
may be considerably smaller than that of the quinacridone samples evaluated. A third factor affecting the lightfastness of 2,9disubs tituted quinacridones is likely the nature of the sub stituent* i.e., whether it is electron-donating or electronwithdrawing.
VII. EXPERIMENTAL
Preparation of the sample of I submitted to Chestnut Run {polystyrene evaluation) and to Parkersburg, W. Virginia ("Zyter1 nylon).
CiaHgOg
p-aminobenzoic acid
SSE (diethyl)
C26H26N28
2,5-Di(4-carboxyanilino)-3,6dihydroterephthalate ester
*
2,9-Dicarboxyqulnacridone
C22H16N208 2,5-Di(4-carboxyailino)-3,6-
terephthalic acid
DUP050028305
*5-
Hie characterization of the intermediates, C2sH26N28& nd
C22H16N2O8, and the final product, C22H12N206, is reported in Patent Memorandum, CP-75, Polar Quinacridones.
Preparation of 026^26^208
See 1835/12A.
Preparation of C22HI6N2O8
See 1335/12K.
Preparation of C22H12N2O6
See 1335/12L.
Acid Reerystallizatjon of C22H12H2O6
See 1835/12M,N.
Dlmethylformamlde Treatment
See 1835/31A,
Dispersion Milling and Preparation of Calcium Rosinate takes
See 1835/31B,C*
Preparation of xTx-Dioarboxyqulnacridone
See 1835/23E.
Acid Recrystallization of X.X1-(COOH)sQA
See 1835/23P,0.
Pound: C, 65,58 H, 3.70 N, 6.79
C H N0
req C, 66.0 H, 3,0 N, 7.0
Preparation of 2,9-Dlcyano- and 2.9-Dioarboxyamido
SSE (diethyl) + p-aminobenzonitrile --* 2,5-Di(4-cyanoanilino)3,6-dihydroterephthalate
ester C26H24N4O4
i
2,9-Dicyanoquinacridone c 22h 10n 42
4
2,9-Dicyanodlhydroquinacridone
C22H12N4O2
DUP050028306
6
Preparation of C26H24N4O4
See 1507-13. Pound: N, 12.3 12.5
C26H24N4O4 req. N, 12.3
Preparation of C22H12N4O2
See 1507-14. Pound: N, 14.7 C22H12N4O2 req. N, 15,42 14,7
Preparation of C22H10N4O2
See 1507-15. Pound: N, 15.0 C22H10N4O2 req. N, 15.47
Band at 5.99m. suggests the presence of some amide.
Summary of Attempts to Prepare Pure 2.9-Dioyanoquinacrldone
N.B.
Oxidation Medium
Heating Cycle Result
1507-15 Sitol-HaO-NaOH-glycol 2 hr.at 110-20 Oxidation - yes. Some amide present.
1835/5B 11
11 "
"
2 hr. at 80-90 Incomplete oxide'n. Amide - no.
1835/5C "
""
"
2 hr. at 90-100 Oxidation-yes, based on dimethy1formamide soln.;
max " 510,477 448mM>
Amide - little. Low carbon and nitro gen analysis.
1835/5E "
" 2 hr.at 85-95 Incomplete oxida'n. Amide - no
1835/16D Chloranil - TCEB
5 hr. at reflux No oxidation,
2.9-Dicarboxyamldoquinacridone
8SE(Me,Et) + p-arainobenzamide -- 2,5-di(4-C0NH2-anlllne) 3,6-dihydroterephthalate ester
C25H26N4O0
Dowtherm A
2,9-dicarboxyamidoqulnacridone C22H14N4O4
f------ ----- 2,9-dicarboxyamidodihydroqulnacridone
Sitol C22H16N4O4
DUP050028307
-7-
Preparation of CgsHk6^406
See 1835/65A. Pound: C, 62.41 C25H26H406 req.C, 62.8
H, 5.0$
H, 5.44
N, 10.75
N, 12.1
The hand at S, 85m. seems low for the type of carbonyl groups in C25%6%6
Preparation of C22HI6N4O4
See 1835/65B. Pound: C, 67.61 C22H16N4O4 req. 0, 66.0
H, 4.02
H, 4.0
N, 11.64
N, 14.0
IE Speotrum: 2.90 and S.OOy. (-NHa), 3.18m. (> NH), 5.95 and 6;i0p. (> OO). Low nitrogen analysis suggests that this may not be good quality 2,9-(CONHa)aDQA.
Preparation of C22H14N4O4
See 1835/78A. Pound: N, 9.64 C22H14N4O4 req. N, 14.1
The low nitrogen analysis of the product suggests that the desired product was not obtained.
Alternate Synthesis
2 >5-01(4-CONHs-ani1ino)-
3,6-dihydroterephthalate ester
C25H26N4O6
/
2,5-Di(4-CONH-anilino)terephthalate ester
C25H24N4O6
ir
2,9-Dlcarboxyamido QA C22H14N4O4
Preparation of C25H24N4Q6
PPA
See 1876/5B. Pound: N, 11.36 C25H24N4O6 req. N, 11.8
IR Spectrum: 2.80 and 2.99u (-NHs) 3. 16m. (> NH), 5.905.95u (ester> 0*0 and amide>C*0), 6.48m. (terephthalate ester).
Preparation of C22H3.4N4O4
See 1876/15D. Pound: N, 11.28 C22H14N4O4 req. N, 14.1
IR Spectrum: 3.00 and 3.10m- (-NHa). 3.18M* (>NH)> 6.03m* (amides C=0), 6.15p- (acridone > C0).
The red color of this produot suggests that ring closure occurred and the low nitrogen analysis suggests that some hy
drolysis of the amide group also took place.
DUP050028308
- s-
Preparation of 2.9-Dloarboethoxyquinacrldone
SSE (diethyl) + ethyl p-arainobenzoate --> 2,5-Di(4-C00Et-aniline)3,6-dihydroterephthalate ester C30H34N2O8
1
2,9-Dicarboethoxyquinacridone - 2,9-Dioarboethoxydihydroquinacri-
C26H20N26
c 26h 22N26
done
Preparation of C30H34N2O8
See 1835/620. Found: 0, 66.27 H, 6.25
N, 5.29
C30H34N28 neq. C, 65.5 H, 6.18 N, 5.09
IR Spectrum: 3. 19j a (>NH), 5.85p (aromatic esters C-0), 6.O614, (> OO of s-anillnoester).
Preparation of C26H20N2Q6
See 1835/68B. Found: C, 70.75
H, 6.02 N, 6.09
C26H22N2O6 req. 0, 68.2
H, 4.60 N, 6.12
Preparation of C26H20N2O6
See 1507/18. Found; 0, 60.51 H, 4.43 N, 5.45
C26H20N26 beq. C, 68.4 Hj 4.39 N, 6.14
VIII. SUGGESTIONS FOR ADDITIONAL WORK
1. Determine rheological behavior of 2,9-dicarboxy-, 2,9-dicyano-, 2,9-diearboxyamido- and 2,9-dicarboethoxyquinacridones, both as self-colors and as additives for other
quinacridones.
2. Determine outdoor durability of 2,9-dicyano-, 2,9carboxyamido- and 2,9-dicarboethoxyquinacridones.
IX. NOTEBOOK REFERENCES
1507 1835 1876
1894
dc
DUP050028309
KO-709-D By: J . Jackson 9/66 - 7/68