CA1095901A - Disazo pigments, process for their manufacture and use thereof - Google Patents

Abstract

Abstract of the Disclosure Disazo pigments of the formula

Description

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The invention provides useful novel disazo pigments of the formula ~m n 1 Xm ~nzp_ ~ V

N ~ OR ~
CH3COCHCONH ~ _ ~ NHOCCHOCCH3 C 3 OR

wherein ~ represents a hydrogen or halogen atom, Y represents a Cl-C6-alkyl or Cl-C6-alkoxy group, Z represents a C2-C6-alkoxycarbonyl group, m is an integer from 1 to 5, n is an integer from 1 to 4, p is an integer from 1 to 3, while the sum of m + n ~ p is 5, Q represents an oxygen or sulphur atom, V represents a hydrogen or halogen atom, and . ~ - 2 ~

. ., - .

- .

R represents a Cl-C4-alkyl group.

Particularly intcresting disazo pigments are those of the formula ~lzl X~zl O P
(~>
N OR N
1 3 ~ I CF3 CH3COCHCONH ~ ~ NHCOCHCOCH3 OR

~herein R has the indicated meaning, Xl and Yl represent hydrogen or chlorine atoms or methyl groups and Zl represents a hydrogen or chlorine atom, a methyl group or a Cl-C~-alkoxy group.
The pigments of the present invention are obtained by coupling the diazo compound of an amine of the formula B
, `.
. ~.. ....

5~

m ~ ~ n - l ~ v H2N ~<~

with a bis-acetoacetylphenylenediamine of the formula C~3COCI'12COi~}I~lOC5}120CC~
OR

in the molar ratio 2:1.
The diazo component is in particular one of the formula Xl~l H2N ~ `
~F3 wherein Xl, Yl and Zl have the indica~ed meanings.
The following known diazo components may be cited by way of exampLe:

- .
- : . . .,,;, . ,. .. ~

. ~-. . ~

2-amino-4-trifluoromethyl-diphenyl ether 2-amino-2'-chloro-4-~rifluorornethyl-diphenyl ether.
2-amino-3'-chloro-4-trifluoromethyl-diphenyl ether 2-amino-4'-chloro-4-trifluoromethyl diphenyl ether 2-amino-2l~4~-dichloro-4-trifluoromethyl-diphenyl ether 2-amino-2',5'-dichloro-4-trifluoromethyl-diphenyl ether 2-amino-3',4'-dichloro-4-trifluoromethyl-diphenyl ether 2-amino-2',4',S'-trichloro-4-trifl.uoromethyl-diphenyl ether 2-amino~2',4',6'-trichloro-4-trifluoromethyl-diphenyl ether 2-amino-2',3',4',6'-tetrachloro-4-trifluoromethyl-diphenyl ether 2-amino-2',3',4',5',6'-pentachloro-4-trifluoromethyl-diphenyl ether 2-amino-2'-chloro-6'-methyl-4-trifluoromethyl-diphenyl ether 2-amino-4'-chloro-2'-methyl-4-trifluoromethyl-diphenyl ether 2-amino-4'-chloro-3'-methyl-4-trifluoromethyl-diphenyl ether 2-amino-2'-methyl-4-trifluoromethyl-diphenyl ether 2-amino-3'-methyl-4-trifluoromethyl-diphenyl ether 2-amino-4'-methyl-4-trifluoromethyl-diphenyl eLher 2-amino-3',5'-dimethyl-4-trifluoromethyl-diphenyl ether 2-amino-2',4'-dimethyl-4-trifluoromethyl-diphenyl ether 2-amino-2'-methoxy-4-trifluoromethyl-diphenyl ether 2-amino-3'-methoxy-4-trifluoromethyl-diphenyl et'n~r 2-amino-4'-methoxy-4-trihloromethyl-diphenyl ether 2-amino-4'-carboethoxy-4-trifluoromethyl-diphenyl ether 2-amino-4-trifluoromethyl-diphPnyl ether 2-amino-4'-chloro-4-trifluoromethyl--diphenyl ether ~ ~ , , ~

3~

2-amino-5-chloro-4-trifluoromethyl-diphenyl ether 2-amino-2',5-dichloro-4-trifluoromethyl-diphenyl ether 2-amino-4',5-dichloro-4-trifluoromethyl-diphenyl ether 2-amino-2',4',5-trichloro-4-trifluoromethyl-diphenyl ether 2-amino-2',5',5-trichloro-4-trifluoromethyl-diphenyl ether 2-amino-2',4',5',5-tetrachloro-4-trifluoromethyl-diphenyl ether 2-amino-5-chloro-4'-methyl-4-trifluoromethyl-diphenyl ether 2-amino-5-chloro-4'-methoxy-4-trifluoromethyl-diphenyl ether 2-amino-4',5-dichloro-6'-methyl-4-trifluoromethyl-diphenyl ether The diazo components are obtained by reduction of the corresponding nitro-trifluoro-diphenyl ethers, which have been prepared for example from nitro-trifluoromethylbenzenes and phenols, under alkaline conditions, in dimethyl sulphoxide or dimethyl formamide.
The coupling components, which are also known, are obtained in simple manner by treating the corresponding known phenylenediamines with diketene or alkyl acetate. Examples of such phenylenediamines are:
2,5-dimethoxy-1,4-phenylenediamine 2,5-diethoxy-1,4-phenylenediamine 2,5-dipropoxy-1,4-phenylenediamine 2,5-diisopropoxy-1,4-phenylenediamine.

~ ` ' ' The coupling preferably takes place in a weakly acid medium, advantageously in ~he presence of conventional agents that promote the coupling. Such agents are in particu-lar dispersants, for e~ample aralkylsulphonates, such as dodeeylbenzenesulphonate, or l,l'-dinaphthylmethane-2,2'-disulphonic aeid or polycondensation products of alkylene oxides. The dispersion of the eoupling component can also advantageously eontain proteetive colloids, for example methyleellulose or minor amounts of inert organie solvents whieh are sparingly soluble or insoluble in water, for example optionally halogena~ed or nitrated aromatic hydrocarbons, for example, benzene, toluene, xylene, chlorobenzene9 dichloro-benzene or nitrobenzene, and also aliphatic halogenated hydro-earbons, for example earbon tetrachlorlde or trichloro-ethylene, as well as organie solvents whieh are miscible with water, for example, aeetone, ethylene glyeol monomethyl ether~
methyl ethyl ketone,methanol, ethanol or isopropanol.
The eoupling ean also advantageously be carried out by eontinuously eombining an aeid solution of the diazonium salt with an alkaline solution of the eoupling eomponent in a mixing nozzle, whereupon an immediate coupling of the eomponent oeeurs. Care must be taken that the diazo eomponent and the coupling eomponent are present in equimolecular amounts in the mixing nozzle, although a slight excess of coupling component proves to be advantageous. This is most simply accomplished by controlling the pH of the liquid in the mixing nozzle.

. ~ -. . ~ :
. . , , -Furthermore, intense ~urbulent mixing of the two solutions in the miX~ nozzle must be ensured. The resultant colourant disperion is continuously drawn off from the mixing no~zle and the colourant separated by filtration.
Finally, the coupling can also be carried out by suspe~ng the diazo component with the coupling component in the molar ratio 2:1 in an organic solvent and treating the coup ling mixture with a diazotising agent, in particular with an ester of nitrous acid, such as methyl, ethyl, butyl, amyl or octyl nitrite.
The pigments usually precipitate at elevated temperature and can be isolated in pure form by filtration and subsequent removal of any impurities by washing them with an organic solvent.
The pigments have in general a good texture and can be widely used as crude products. If necessary or desired, the crude products can be converted into a finely dipersed form by grinding or kneading, advantageously using grinding assistants, such as inorganic and/or organic salts in the presence or ab-sence of organic solvents. After the grinding procedure, the assistants are removed in the conventional manner: soluble inorganic salts for example with water, and water-insoluble assistants for example by steam distillation.
The properties of the crude pigments can often be improved by treating them with organic solvents, preferably those having a boiling point above 100C. Particularly ., ~ , ., `
::

suitable organic solvents are: benzenes which are substituted by halogen atoms, alkyl or nitro groups, for example xylene, chlorobenzene, o-dichloroben~lene or nitroben~ene, as well as pyridine bases, such as pyridine, picoline or quinoline, and also ketones, for example, c:yclohex-anone; ethers, for example ethylene glycol monomethyl and monoethyl ether; amides, such as dimethyl formamide or N-methylpyrrolidone, as well as sulpho-xoneor water under pressure.
The aftertreatment is effected preferably by heating the pigment in the solvent to 100-150C, when in many cases an increase in the gra~ular size occurs. The fastness to light and migration of the resultant pigmen~s are thereby favourably influenced, The pigments according to the invention are suitable for colouring organic material of high molecular wPight, for example cellulose ethers and esters, polyamides and polyure-thanes or polyesters, acetyl cellulose, nitrocellulose, natural resins or synthetic resins, such as polymerisation or condensation resins,for example aminoplasts, in particular urea and melaminelformaldehyde resins, alkyd resins, phenolic plastics, polycarbonates, polyolefins, such as polystyrene, polyvinyl chloride, polyethylene, polypropylene, polyacrylonitrile, polyacrylates, rubber, casein, silicone and silicone resins, individually or in mlxtures.
It is immaterial whether the cited materials of high ~ ~ 5~ ~ ~

molecular weight are in the form of plastics, melts or in the form of spinning solutions, varnishes, paints or printing inks. Depending on the use to which they are put, it is advantageous to use the new pigments as toners or in the form of preparations, In addition to the p~lre pigment, the preparations can a~ditionally contain, for example, abietic acid or esters thereof, ethyl cellulose, cellulose ace~obutyrate, alkaline earth salts of higher fatty acids, fatty amines~ for example, stearylamine or rosinamine, vinyl chloride/vinylacetate copolymers, polyacrylonitrile or polyterpene resins or water-soluble dyes, for example dyestuff sulphonic acids or the alkaline earth salts thereof.
The pigments of the present invention are distinguished by good fastness to light, migration and weather. They also have good dispersibility, transparency and brilliance, as well as excellent resistance to alkali and high colour strength. Compared with US patents 2,591,470 and 3,872,078, they are distinguished by improved lightfastness and resistance to weathering.
In the following Examples which illustrate the invention, the parts and percentages are by weight unless otherwise indicated.

Example 1 25.3 parts of 2-amino-4~trifluoromethyl-diphenyl ether are stirred in 300 parts by volume of glacial acetic acid with 25 parts by volume of conc. hydrochlo~ic acid, where-upon the chlorohydrate of the base is formed. The reaction mixture is then cooled to -5C by addition of 300 parts of ice and diazotised by adding 25 parts by volume o 4N sodium nitrite. The yellow diazo solution is stirred at 0 to 5 C
until only traces of nitrous acid can still be detected. The diazo solution is then filtered clear by addition of decolouris-ing carbon. The filtrate is adjusted to pH 4 by addition of 48 parts of sodium acetate. Simultaneously, 16.8 parts of 2,5-dimethoxy-1,4-bis-acetoacetylaminobenzene are dissolved in 800 parts of water with 12 parts by volume of 40 % sodium hydroxide solution and 5 parts of n-butylsulphoricinoleate are added. This solution is filtered clear with 0.5 part of decolourising carbon and then added dropwise, with efficient stirring, to the diazo solution over the course of 1 to 1 1/2 hours. The temperature of the reaction mixture riseS to 15 to 20 C. When the dropwise addition is complete, no more diazo compound can be detected in the mixture. The coupling mixture is stirred for 1 hour at room temperature, then heated to 80-85C and filtered hot. The filter cake is washed ~ree of salt and dried in vacuo at 95 -100C, aff-ording 40 parts of a yellow colourant of the formula , . .

~F3 ~ C--7F3 C~13COC~ICO`~ N~OCG`IIOCCH~
O C1l13 40 parts of this pigment are stirred in 600 parts by volume of dimethyl formamide for 8 hours at 145-150 C, whereupon it assumes a homogeneous crystalline form. Microscopic examination reveals fine, yellow particles 5-15 ~ in length.
After filtration at 140C, washing with boiling cellosolve until the filtrate runs clear, expelling the cellosolve with ethanol and drying, there are obtained 10.2 parts of a brilli-ant yellowish orange pigment dye. It colours plastics, such as polyvinyl chloride, in yellowish orange shades of excellent fastness to migration. The treatment in the organic solvent can be carried out direct with the moist filter cake without first drying it. The moist filter cake can be stirred in picoline at 100-120C, filtered, washed with methanol and subsequently with dilute hydrochloric acid, or it is stirrred in chlorobenzene, o-dichlorobenzene or nitrobenzene, and freed from water by azeotropic distillation and then worked up as described hereinabove. The pigment colours polyvinyl chloride , , ., . - - , -. 1 .- ,:, : . : .
:- : ,: ~ :: :, ..
- -: ~ . .. , . , ~s~

in yellowish orange shades of excellent fastness to ligh~, weather and migration.
The corresponding pigments with chlorine atoms instead of trifluoromethyl groups are disclosed in US patent specifi-cation 2,591,470, but they have po~rer fastness to light and weathering in the colouration of PVC and lacquers, The following Table lists further coloura~ts which are obtained by coupling the diazotised bases of column I with the bisacetoacetic arylides of the diamines of column II.
Column III indicates the shade of polyvinyl chloride sheets coloured with 0.2 % of these pigments.

' ' ~ , ~s~

. Ex. Diazo Component Coupling ~omponent ~ Sha 2 2-amino-4-trifluoro- 2,5-diethoxy-1,4- yellowish methyldiphenyl ether phenylenediamine orange . 3 ,l 2,5-dipropoxy-1,4- yellowish phenylenediamine orange

4 2-amino-2' chloro-4- 2~5-dimethoxy-1,4- yellowish trifluoromethyl- phenylenediamine orange diphenyl ether . 5 ,l 2,5-diethoxy-1,4- yellowish phenylenediamine orange . 6 2-amino-4~-chloro-4- 2,5-dimethoxy-1,4- orange trifluoromethyl- phenylenediamine diphenyl ether 7 ll 2,5-diethoxy-1,4- orange phenylenediamine 2,5-diisopropoxy- yellow 1,4-phenylene diamine 9 2-amino-2',4'-dichlo- 2,5-dimethoxy-1,4- yellowish ro-4-trifluoro- phenylenediamine orange methyl-diphenyl ether 10 ll 2,5-diethoxy-1,4- yellowish phenylenediamine orange ll 2-amino-2'?4',5'-tri- 2,5-dimethoxy-1,4- orange chloro-4-trirluoro- phenylenediamine methyl-diphenyl-ether 12 " . 2,5-diethoxy-1,4- orange phenylenedi~mine 13 2 amino-3'-methyl-4- 2,5-dimethoxy-1,4- yellowish trifluoromethyl- phenylenediamine orange diphenyl ether ]4 ~ . 2,5-diethoxy-1,4- orange ..
phenylenediamine _ _ _ . ~. , : . .

~0~ 8~

~ . . __ Ex. Diazo Component ¦Co~lpling Component Shade in PVC
. .~ . I _ ~ _ I
2-amino-3',5'-di- 2,5-dimethoxy-1,4- orange methyl-~-trifluoro- phenylenediamine methyl-diphenyl ether l~ ll 2,5-diethoxy-1,4- orange . phenylenediamine 17 2-amino-2'-methoxy- 2,5-dimethoxy-1,4- orange 4-trifluoromethyl- phenylenediamine diphenyl ether 18 ,l 2,5-diethoxy-1,4- orange phenylenediamine 19 2-amino-4'-chloro-2'- 2,5-dimethoxy-1,4- orange methyl-4-trifluoro- phenylenediamine methyl-diphenyl ether 20 ll 2,5-diethoxy-1,4- orange phenylenediamine 21 2-amino-5-chloro-4- 2,5-dimethoxy-1,4- orange trifluoromethyl-di- phenylenediamine phenyl ether 22 ll 2.5-diethoxy-1,4- orange phenylenediamine 23 2-amino-4',5-dichlo- 2,5-dimethoxy-1,4- yellowish ro-4-trifluoro- phenylenediamine orange methyl-diphenyl ether 24, ll 2,5-diethoxy-1,4- orange ..
. phenylenediamine 25 2-amino-2',5'-5-tri- 2,5-dimethoxy-1,4- orange chloro-4-trifluoro- phenylendiamine methyl-diphenyl ether 26 It 2,5-diethoxy-1,4- orange _ phenylenediamine .. _ .. _ . . .. _ .. . :

p~

Ex.l Diazo Component I Coupling Component Shade ln PVC

27 ¦ 2-amino-2',4',5',5-tetra- 2,5-dimethoxy-1,4- orange I chloro-4-trifluoromethyl- phenylenediamine diphenyl ether 2S .. 2,5-diethoxy- 1,4- orange phenylenediamine 2~ 2-amino-2'-methoxy-5- 2,5-dimethoxy-1,4- orange chloro-4-trifluoro- phenylenediamine methyl-diphenyl ether ~ 2,5-diethoxy-1,4- orange phenylenediamine 31 2-amino-4',5-dichloro-6'- 2,5-dimethoxy-1,4- orange methyl-4-trifluoro- phenylenediamine methyl-diphenyl ether 32 ll 2,5-diethoxy-1,4- orange phenylenediamine 33 2-amino-4'-carboethoxy- 2,5-dimethoxy-1,4- yellowish 4-trifluoromethyl-di- phenylenediamine orange phenylene ether ¦34 ll 2,5-diethoxy-1,4- yellowish phenylenediamine orange 135 2-amino-4-trifluoro- 2,5-dimethoxy-1,4- yellowish methyl-diphenylthio phenylenediamine orange ethe l ~ ~

f~

~ .
. .

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Example k~
2 g of the pigment obtained in Example 1 are gound with 36 g of toner dehydrate, 60 g of boiled linseed oil of medium viscosity and 2 g of cobalt linoleate on a three roll mill. The yellow prints obtained with the resultant colour paste are strong and of excellent lightfastnessO
~,~
Example ~
0.6 g of the pigment obtained in Example 1 is mixed with 67 g of polyvinyl chloride, 33 g of dioctyl phthalate, 2 g of dibutyl tin dilaurate and 2 g of titanium dioxide and the mixture is processed to a thin sheet for 15 minutes at 160 C on a roll mill. The yellowish orange colouration obtained is strong and fast to migration, heat and light.

3 ~ ~-}
Example ~
10 g of titanium dioxide and 2 g of the pigment obtained in Example 1 are ground for 48 hours in a ball mill with 88 g of a mixture of 26 4 g of coconut alkyd resin, 24 g of melamin~/orm~1dehyde resin (~0 % solids content), 8.8 g of ethylene glycol monomethyl ether and 28.8 g of xylene.
The resultant lacquer is sprayed onto an aluminium sheet, pre-dried for 30 minutes at room temperature and then stoved for 30 minutes at 120C, giving a brilliant orange finish which has very good colour strength and is distinguished by very good fastness to overstripe bleeding, light and weathering.

Claims (6)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. Disazo pigments of the formula wherein X represents a hydrogen or halogen atom, Y represents a C1-C6-alkyl or C1-C6-alkoxy group, Z represents a C2-C6-alkoxycarbonyl group, m is an integer from 1 to 5, n is an integer from 1 to 4, p is an integer from 1 to 3, while the sum of m + n + p is 5, Q represents an oxygen or sulphur atom, V represents a hydrogen or halogen atom, and R represents a C1-C4-alkyl group.

2. Disazo pigments according to claim 1 of the formula wherein R is as defined in claim 1, X1 and Y1 represent hydrogen or chlorine atoms or methyl groups and Z1 represents a hydrogen or chlorine atom, a methyl group or a C1-C4-alkoxy group.

3. A process for the manufacture of disazo pigments of the formula wherein X represents a hydrogen or halogen atom, Y represents a C1-C6-alkyl or C1-C6-alkoxy group, Z represents a C2-C6-alkoxycarbonyl group, m is an integer from 1 to 5, n is an integer from 1 to 4, P is an integer from 1 to 3, while the sum of m + n + p is 5, Q represents an oxygen or sulphur atom, V represents a hydrogen or halogen atom, and R represents a C1-C4-alkyl group, which process comprises coupling the disazo compound of an aminelofthe formula with a bis-acetoacetylphenylenediamine of the formula in the molar ratio 2:1.

4. A process according to claim 3 wherein the disazo component is an amine of the formula

5. A method of pigmenting organic material of high molecular weight which comprises the use of the pigments according to claims 1 and 2.

6. Organic material of high molecular weight which contains a pigment according to claim 1.