S. Fang et al.
Dyes and Pigments 176 (2020) 108225
2.2.2. General procedure of coupling
reaction of the hydroxyl groups in the corresponding parent dyes, dye
1a-1e with p-toluene isocyanate. Their structures were well confirmed
by 1H NMR, 13C NMR, FT-IR, MS and Elemental analysis.
N-phenyldiethanolamine (3.62 g, 0.02mol) was dissolved in hydro-
chloric acid solution (30 ml, 10%) at 0–5 �C. And the diazonium solution
was added dropwisely into the coupling component solution at 0–5 �C. It
can be seen immediately generated the dye 1d. This reaction mixture
was stirred for 3 h and monitored by using starch iodide paper and H-
acid. The resulting precipitated product was filtered and further washed
with water, recrystallized from acetone to give the pure dye 1d (5.35 g,
yield, 81.1%). Dye 1e (yield, 78.2%) was obtained as the same method.
2a: Yield 89.4%; mp 173–174 �C; 1H NMR (400 MHz, DMSO‑d6,δ,
ppm): 9.589 (s, 1H, –NH–), 8.373 (d, J ¼ 9.2 Hz, 2H, Ar–H), 7.948 (d, J
¼ 9.2 Hz, 2H, Ar–H), 7.859 (d, J ¼ 9.2 Hz, 2H, Ar–H), 7.352 (d, J ¼ 5.6
Hz, 2H, Ar–H), 7.089 (d, J ¼ 8.4 Hz, 2H, Ar–H), 6.960 (d, J ¼ 9.2 Hz, 2H,
Ar–H), 4.304 (t, J ¼ 12 Hz, 2H, –CH2-O-), 3.767 (t, J ¼ 12 Hz, 2H,
-N–CH2–), 3.604 (q, J ¼ 20.8 Hz, 2H, –CH2CH3), 2.229 (s, 3H, –CH3),
1.196 (t, J ¼ 14 Hz, 3H, –CH2CH3). 13C NMR (100 MHz, DMSO‑d6, δ,
ppm): 156.686, 153.931, 152.095, 147.371, 143.342, 136.834, 131.881
( � 2), 129.563( � 2), 126.570( � 2), 125.422( � 2), 122.962( � 2),
118.695( � 2), 112.122, 61.787, 49.132, 45.589, 20.768, 12.482. MS
(þESI): m/z (%) ¼ 447.55 (100) [Mþ]. FT-IR (KBr, cmÀ 1): 3329(N–H,
2.2.3. Synthesis of azo disperse dyes (2d)
Azo disperse dye 1d (3.30 g, 0.01mol) was stirred in the dry
dichloromethane (300 ml) at room temperature with the magnetic
stirrer. Triethylamine (2.02, 0.02mol) was slowly added into solution
1d. p-toluene isocyanate (2.77 ml, 0.022mol) dropwisely added into the
dissolved solution 1d within 15 min to confirm 1d could be completely
reacted. This reaction was carried out overnight for stirring at room
temperature, and went to completion by monitoring on silica gel
aluminum based plates kisel gel 60 F254 Merck, Germany. The reaction
mixture was then successively washed with sodium carbonate solution
(10%), dilute hydrochloric acid solution and deionized water to
neutrality, and separated by a separating funnel throughout the washing
process for every step. The solvent was removed with rotavapor under
reduced pressure, and the residual solid was then washed with water
and dried in oven at 100 �C. The obtained crude product was recrys-
tallized from acetone to give dye 2d (yield, 71.3%), which performed a
constant molar extinction coefficient and TLC purity. The rest four dyes
2a, 2b, 2c and 2e were also obtained as the same method.
–
–
–
–NHCOO–), 1701(C O, –NHCOO–), 1598(C C, aromatic). Calculated
–
for C24H25O4N5: C, 64.43; H, 5.59; N, 15.66%; Found: C, 64.35; H, 5.62;
N, 15.70%.
2b: Yield 81.0%; mp 168–169 �C; 1H NMR (400 MHz, DMSO‑d6,δ,
ppm): 9.575 (s, 1H, –NH–), 8.454 (s, 1H, Ar–H), 8.277 (d, J ¼ 9.2 Hz,
1H, Ar–H), 7.881 (d, J ¼ 9.2 Hz, 2H, Ar–H), 7.808 (d, J ¼ 8.8 Hz, 1H,
Ar–H), 7.337 (d, J ¼ 12 Hz, 2H, Ar–H), 7.084 (d, J ¼ 8.4 Hz, 2H, Ar–H),
6.996 (d, J ¼ 9.6 Hz, 2H, Ar–H), 4.308 (t, J ¼ 11.6 Hz, 2H, –CH2-O-),
3.788 (t, J ¼ 11.6 Hz, 2H, -N–CH2–), 3.624 (q, J ¼ 20.8 Hz, 2H,
–CH2CH3), 2.225 (s, 3H, –CH3), 1.204 (t, J ¼ 14 Hz, 3H, –CH2CH3). 13
C
NMR (100 MHz, DMSO‑d6, δ, ppm): 153.918, 152.874, 152.701,
147.342, 143.959, 136.813, 132.798, 131.902( � 2), 129.564( � 2),
127.213, 126.224( � 2), 123.885( � 2), 119.047, 118.557, 112.369,
61.781, 49.205, 45.708, 20.764, 12.501. MS (þESI): m/z (%) ¼ 482.33
(100) [M þ Hþ], 483.37 (55). FT-IR (KBr, cmÀ 1): 3238 (N–H,
–
–
–
–NHCOO–), 1699 (C O, –NHCOO–), 1598 (C C, aromatic). Calculated
–
2.3. Dyeing and fastness measurement
for C24H24O4N5Cl: C, 59.81; H, 4.98; N, 14.54%; Found: C, 59.77; H,
5.01; N, 14.62%.
The PA fabrics were scoured in a bath including 2 g/L non-ionic
surfactant and 1 g/L sodium carbonate at 95 �C for 30 min, then
rinsed with water and dried at room temperature.
2c: Yield 83.5%; mp 221–222 �C; 1H NMR (400 MHz, DMSO‑d6,δ,
ppm): 9.564 (s,1H, –NH–), 8.787 (s, 1H, H of nitrothiazole cycle), 7.852
(d, J ¼ 9.2 Hz, 1H, Ar–H), 7.321 (d, J ¼ 5.6 Hz, 2H, Ar–H), 7.076 (d, J ¼
8 Hz, 2H, Ar–H), 6.965 (d, J ¼ 9.6 Hz, 1H, Ar–H), 6.909 (s, 1H, Ar–H),
4.345 (t, J ¼ 10.8 Hz, 2H, –CH2-O-), 3.894 (t, J ¼ 10.8 Hz, 2H, -N–CH2–),
3.712 (q, J ¼ 10.8 Hz, 2H, –CH2CH3), 2.526 (s, 3H, Ar-CH3), 2.220 (s,
3H, Ar-CH3), 1.232 (t, J ¼ 14 Hz, 3H, –CH2CH3). 13C NMR (100 MHz,
DMSO‑d6, δ, ppm): 182.551, 155.793, 153.811, 147.096, 145.803,
145.499, 141.565, 136.728, 131.956, 129.596( � 2), 121.252( � 2),
118.682, 113.818, 113.345, 61.950, 49.597, 46.368, 20.765, 18.194,
12.853. MS (þESI): m/z (%) ¼ 469.26 (100) [M þ Hþ]. FT-IR (KBr,
The purified dyes and disperse agent NNO (1:1, w/w) were milled by
using glass beads and mechanical stirrer to dye dispersions whose
average particle size was smaller than 0.5 mm, that was measured by a
Laser Diffraction particle size analyzer (Mastersizer 3000, Malvern). For
every one of ten dyes (1a-1e, 2a-2e), a set of dye baths containing
different initial concentration of dye ranging from 0.25% to 5.00% (o.w.
f) and 1 g/L (NH4)2SO4 were prepared, the bath ratio was 50:1. Dyeing
was performed in an oil laboratory dyeing machine (Rapid, China) by
raising the dyebath temperature from 40 �C to 120 �C at a rate of 1 �C/
min and holding for 60 min before cooling to 80 �C. Two pairs of dyes
(1a and 2a, 1d and 2d) were selected to study the dyeing rate curves,
various dyed PA samples were produced by stopping the process at an
interval of 10 min from 40 �C to 120 �C for 80min. The dyed PA fabrics
were soaped with an aqueous solution (2 g/L standard soap powder) at
95 �C using a liquor ratio of 50:1 for 15 min, rinsed and air dried.
The K/S values were calculated from the reflectance values at the
appropriate wavelength of maximum absorbance for each dyeing using
a Datacolor SF 600 spectrophotometer (USA) under illuminant D65 via a
10� standard observer. The dyeings were measured at five different
points to get the average results and the levelness was estimated by
measuring five points of the test sample and calculating the mean value
of color differences (ΔE) between the five points. The dyeings of 1:1
standard depth for every dye were used to evaluate the fastness prop-
erties. The standard methods were respectively ISO 105-C06 for
washing, ISO 105-B02 for lighting, ISO 105-X12 for rubbing, ISO 105-
X11 for sublimation.
cmÀ 1): 3394 (N–H, –NHCOO–), 1741 (C O, –NHCOO–), 1597 (C C,
–
–
–
–
aromatic). Calculated for C22H24O4N6S: C, 56.41; H, 5.13; N, 17.95%;
Found: C, 56.28; H, 5.17; N, 18.02%.
2d: Yield 71.3%; mp 209–210 �C; 1H NMR (400 MHz, DMSO‑d6,δ,
ppm): 9.579 (s, 2H, –NH–), 8.387 (d, J ¼ 9.2 Hz, 2H, Ar–H), 7.967 (d, J
¼ 8.8 Hz, 2H, Ar–H), 7.871 (d, J ¼ 9.2 Hz, 2H, Ar–H), 7.329 (d, J ¼ 5.2
Hz, 4H, Ar–H), 7.083 (d, J ¼ 3.6 Hz, 4H, Ar–H), 7.062 (d, J ¼ 4.4 Hz, 2H,
Ar–H), 4.322 (t, J ¼ 11.6 Hz, 4H, –CH2-O-), 3.866 (t, J ¼ 10.8 Hz, 4H,
-N–CH2–), 2.225 (s, 6H, –CH3). 13C NMR (100 MHz, DMSO‑d6, δ, ppm):
156.575, 153.922, 152.129, 147.544, 143.689, 136.790( � 2), 131.910
( � 2), 129.582( � 2), 126.434( � 2), 125.452( � 4), 123.073( � 4),
119.004, 118.697, 112.398, 61.561( � 2), 50.032( � 2), 20.765( � 2).
MS (þESI): m/z (%) ¼ 597.81 (100) [M þ Hþ]. FT-IR (KBr, cmÀ 1): 3325
–
–
–
–
(N–H, –NHCOO–), 1707 (C O, –NHCOO–), 1600 (C C, aromatic).
Calculated for C32H32O6N6: C, 64.43; H, 5.37; N, 14.09%; Found: C,
64.52; H, 5.34; N, 14.02%.
2e: Yield 88.9%; mp 215–216 �C; 1H NMR (400 MHz, DMSO‑d6,δ,
ppm): 9.576 (s, 2H, –NH–), 8.464 (s, 1H, Ar–H), 8.277 (d, J ¼ 8.8 Hz, 1H,
Ar–H), 7.889 (d, J ¼ 9.2 Hz, 2H, Ar–H), 7.807 (d, J ¼ 8.8 Hz, 1H, Ar–H),
7.333 (d, J ¼ 7.6 Hz, 4H, Ar–H), 7.101 (d, J ¼ 8 Hz, 4H, Ar–H), 7.081 (d, J
¼ 8 Hz, 2H, Ar–H), 4.331 (t, J ¼ 11.6 Hz, 4H, –CH2-O-), 3.883 (t, J ¼ 11.2
Hz, 4H, -N–CH2–), 2.224 (s, 6H, –CH3). 13C NMR (100 MHz, DMSO‑d6, δ,
3. Results and discussion
3.1. Characterization
ppm):
153.912,152.772,147.538,144.284,136.775,132.954(
�
The urethane-containing dyes, dye 2a-2e were obtained through the
3