CA1077928A - Acyldihydroxybenzene heterocyclic azo dyes for metallized polyolefins - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE
Azo dyes of the formula:
are provided wherein A is or where R6 and R7 are independently hydrogen, cyano, nitro, halogen, lower alkyl, lower alkylsulfonyl, trifluoromethyl, carbalkoxy o?
phenyl and R8 and R9 are independently hydrogen, lower alkyl, lower alkoxy, halogen, nitro, sulfamyl, N,N-(dilower alkyl)-sulfamyl, cyano and lower alkyl sulfonyl and wherein R is lower alkyl, benzyl or phenyl. The dyes when applied to metallized polyolefin fabrics, particularly nickel-containing polypropylene fabrics, produce strong, bright shades which are exceptionally fast to light, dry cleaning, crocking, gas and heat.

Description

The present invention relates to azo dyes useful in the dyeing of polyolefin fabrics, or textiles. More particularly, the invention relates to acyldihydroxybenzene azo dyes prepared from heterocyclic bases and which have utility in the dyeing of metallized, or metal containing polyolefin, especially nickel-containing polypropylene textile materials.
Polypropylene, because of its excellent mechanical strength, high elasticity and resistance to solvents, has found increased utility in recent years as filaments, yarns, fabrics, ropes and the like. Commercially available polypropylene materials generally contain metals or metal salts or chelates to provide stability against degradation due to light. These metals or metal salts or chelates also serve to provide reactive sites for dyes.
Dyes, more particularly, chelatable dyes, having specific utility in the dyeing of such metal-containing, or metal-modified, polypropylene are reported extensively in the .~ literature. Chelatable aæo dyes disclosed for use in dyeing metallized polyolefin commonly contain o,o'-dihydroxyazo; o-~, hydroxy-o'-carboxyazo; o-hydroxy-o'-aminoazo; or o-carboxy-o'-~`; aminoazo chelatable groups. Certain azomethine structures ; similarly substituted ortho to the -C=N- link have also been ` reported.
: .
Thus, for example, Siegrist et al, United States Patent ,.~ No. 3,399,027, disclose a process for dyeing polyolefins containing organic nickel chelate complexes with an aqueous dispersion of an azomethine dye. As the azomethine dyes there ~ ~ .

~, are disclosed dyes of the formulas:
X
Y4~N=CH~ or y ~ N=CH~

`.'' - 1 - ~
i'. ¢l ~

. -Where X is OH or COOH, and Y is phenylazo or naphthylazo.
Mohr et al, United States Patent No. 3, 389 ,956,disclose the dyeing of nickel modified polypropylene textiles with an acyl-o,o'-dihydroxyazo or acyl-o-hydroxy-o'-carboxyazo dye of the formula:
y OH

~N=N~ OH
x f=o R
Y being hydroxy or carboxy.
Dyes having chelatable groups of the o,o'-dihydroxyazo and o-hydroxy-o'-carboxyazo type, however, do not produce acceptable shades on metallized polypropylene. Although these groups apparently bind strongly to the metal compound contained in the polypropylene and give dyeings having excellent fastness to rubbing, washing and dry cleaning, they tend to produce dull and rather weak colors. These dyes are also disadvantageous in that there is a drastic change in hue between the unchelated and chelated dyes which can cause uneveness on the metallized fiber depending on the concentration of metal throughout the fiber. This difference in hue between chelated and unchelated dyes may also cause differences in hue between the dyed pile of a carpet of a metal-containing polypropylene and the carpet ~`
backing, which is usually made from non-chelatable materials.
It is an object of the present invention, therefore, to provide dyes suitable for dyeing metal-containing, or metal-modified, polyolefins, and particularly, polypropylene, and which avoid or minimize the problems associated with the dyes hereto-fore employed in the art.

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This and other objects of the invention will become apparent from the following summary and description of preferred embodiments.
According to the present invention there is provided a compound of the formula A-N=W~ OEI ( I ) C=O
R
wherein A is R7 R ~

` where R6 and R7 are independently selectea from hydrogen; cyano;
nitro; chlorine; bromine; lower alkyl; lower alkylsulfonyl;
trifluoromethyl; R'OOC-, where R' is lower alkyl; or phenyl; and R8 and R9 are independently selected from hydrogen, lower alkyl, ; lower alkoxy, chlorine, bromine, nitro, sulfamyl, N,N- (dilower alkyl)-sulfamyl, cyano, and lower alkyl sulfonyl; and R is lower alkyl,~benzyl, or phenyl which is unsubstituted or substituted with up to two substituents independently selected from lower alkyl, lower alkoxy, chlorine and bromine.
According to another aspect of the invention there ; is provided metallized polyolefin dyed with dye of the formula (I) wherein A and R are as defined above.
In the dyes of the present invention represented by the formula (I), A is a heterocyclic radical derived from

2-aminothiazole or 2-aminobenzothiazole. The heterocyclic diazo component derived from 2-aminothiazole is unsubstituted or mono "'

- 3 -~07792~

or disubstituted with cyano, nitro, halogen, lower alkyl, lower alkylsulfonyl, trifluoromethyl, carbalkoxy (R'OOC-, where R' is lower alkyl) or phenyl. The heterocyclic diazo component derived from 2-aminobenzothiazol~ is unsubstituted or mono or disubstituted in the benzene ring with lower alkyl, lower alkoxy, halogen, nitro, sulfamyl (H2NSO2-), N,N-~dilower alkyl)-sulfamyl, cyano, or lower alkyl sulfonyl. The term "lower" as employed herein designates a carbon content of from 1 to 4 carbon atoms.
Halogen includes chlorine and bromine. Examples of the alkyl and alkoxy groups which can be present on the diazo components include, for example, methyl, ethyl, propyl, isopropyl, butoxy, ethoxy, propoxy and the like.
The member R of the dyes according to the present invention is selected from lower alkyl, benzyl and phenyl. The phenyl may be optionally substituted with up to two substituents independently selected from lower alkyl, lower alkoxy, chlorine and bromine. Typically, the phenyl group will be unsubstituted.
The dyes are made in conventional ways by diazotizing ,; an amino heterocyclic base of the formula A-NH2 and coupling the diazotized base into the appropriate 1-acyl-2,4-dihydroxy-benzenes.
Typical amino heterocycles useful as the diazotizable base in the coupling reaction are 2-amino-5-nitrothiazole, 2-amino-5-bromothiazole; 2-amino-5-trifluoromethylthiazole;
2-amino-4-carbethoxythiazole, 2-amino-4-methyl-5-nitrothiazole, 2-aminobenzothiazole, 2-amino-6-ethoxybenzothiazole, 2-amino-6-; methoxybenzothiazole, 2-amino-6-nitrobenzothiazole, 2-amino-5-methylbenzothiazole, 2-amino-4,6-dichlorobenzo-thiazole, 2-amino-5,6-dichlorobenzothiazole, 2-amino-6-sulfamylbenzothiazole, 2-amino-6-(N,N-dimethylsulfamyl)-benzothiazole, 2-aminobenzo-' C~

.

thiazole-6-methylsulfone and 2-amino-5-bromobenzothiazole. The choice of suitable heterocyclic bases is believed to be limited only by practical considerations such as availability, ease of handling and the like.
Suitable l-acyl-2,4-dihydroxybenzenes which can be used as couplers include 2,4-dihydroxybenzophenone, 2,4-dihydroxy-acetophenone and 2,4-dihydroxypropiophenone. All l-acyl-2,4-dihydroxybenzenes where R is as defined above are believed to be useful in preparing dyes according to the present invention, which when applied to metal-containing, particularly nickel-containing polypropylene, will give the outstanding properties noted above. The actual choice of couplers, however, will generally be limited by economic considerations and availability.
Diazotization of the amino heterocyclic base and coupling of the diazotized base into the appropriate couplers are also carried out in conventional ways. Diazotization of the amine is effected by dissolving sodium nitrite in concentrated sulfuric acid, heating to a temperature of about 60 - 70C, cooling the resulting solution to about 0C and adding thereto first a mixture of acetic acid and propionic acid and thereafter the amino heterocyclic base. Alternatively, the amino hetero-cyclic base can be mixed with concentrated phosphoric acid, r, stirred to solution at temperatures up to 65 C, and cooled to below 0C. To the cold solution nitrosylsulfuric acid or sodium nitrite are added dropwise with stirring.
The coupling reaction is carried out by adding the diazonium salt to a cold solution of the respective coupler slurried in propionic acid - acetic acid mixture. Dimethyl-formamide may, advantageously, be added to the coupler solution.
The mixture is allowed to react for 8 - 24 hours at room '.' ~,`i ' temperature and is thereafter filtered and washed neutral with water. The desired azo product is thus obtained in the form of a wet cake.
The azo dyes (I) of the present invention have ~-outstandiny utility in the dyeing of metal-containing polyolefins and especially, nickel-containing polypropylene fiber materials.
The dyed metal-modified polypropy~ene fiber materials according to the present invention include as the starting polypropylene fiber material any of the conventionally produced polypropylene materials generally designated in the textile art as "poly-propylene fibers" including homopolymers and copolymers, and which contain Werner complex-forming metal such as aluminum, nickel, zinc, chromium or cobalt, either as such or in the form of its salts or chelates. These fibers are commonly referred to as metallized, metal-containing or metal-modified fibers. The exact metal content of these fibers is not generally specified :
. by the manufacturer but is believed to vary within the range of about 0.1 to about 2.0 weight percent. The metal improves the . . .
dyeing properties of the fiber materials and also serves to stabilize the materials against degradation due to light and heat.
Nickel-containing polypropylene materials dyed with the structure of formula (I) have been shown to have excellent fastness properties. Such nickel-containing polypropylene materials are ; available commercially, for example, under the trademark HERCULON.
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To prepare the dye for application to the metal-modified fiber substrates, it must be suitably dispersed. This may be done by any of several well-known methods, e.g. milling as in a ball-mill with dispersing agents such as lignin sulfonic acid materials. The resultant aqueous dispersion can be dried, as in '' .: ,:

1~779Z8 a spray-dryer, or preserved and used as a paste. Standardization to any desired lower strength can be done with inert colorless diluents such as water soluble inorganic salts, soluble organic materials or additional dispersant for powders, or water for pastes. Other materials such as preservatives, foam-control agents, and wetting agents (for powders) may be added as desired.
Dispersed pastes are made by wet milling the azo material in conventional equipment in the presence of a dispersing agent, preferably sodium lignin sulfonate or sodium alkylnaphthalene sulfonate. Various other commercially available dispersing agents, such as sodium salts of carboxylated polyelectrolytes and the naphthalene sulfonates, e.g., the condensation products of sulfonated naphthalene and formaldehyde, such as sodium dinaphthylmethane disulfonate, are conveniently used. The disperse paste may be cut or standardized to a standard strength with water. The final color content of the ~ finished paste is usually from 5-40 percent by weight (pure color) ,~ active dye base.
Disperse powders are prepared by wet milling color in the presence of a dispersant, such as those mentioned hereabove, in equipment such as a ball-mill, Werner-Pfleiderer mill or attritor. The dispersed material is oven or spray dried and l micropulverized if necessary to provide the dispersed powder.
The color is cut or standardized to a standard strength in a blender with a diluent, such as the same or another dispersant or dextrin. A wetting agent, such as sodium cetyl sulfate or an alkylaryl polyether alcohol may be added to aid in wetting out the product when it is placed in the dye bath. Disperse powders are usually cut or standardized to 10-50 percent by weight color content (pure color).
: ' ~.1 ., ~,.
., ~077928 The dlsperse dyes may be applied to the metal-containing polypropylene fibers or fabrics in a manner conventional in the dyeing of disperse dyestuffs and may be applied, for example, as neutral, acidic, or alkaline aqueous suspensions, with the use of dispersing agents, from a dyebath, preferably at temperatures of from 50C to 105C. When temperatures of less than about 100C
are employed, it is generally advantageous to add a customary carrier substance. These dyes can also be applied to the metal-containing polypropylene fabrics by a printing process. The printing paste can be thickened with customary thickening agents and may also contain other additives conventionally used with printing pastes. The printing paste is expediently applied to the fabric by a printing block or a roller, whereupon the printed fabric is dried and steamed at a temperature between 105C and 110C. After the dyeing or printing of the polypropylene material, it is treated with a hot aqueous soap solution rinsed and dried. As suitable dyeing and printing techniques there may be mentioned those described in United States Patent Nos. 3,399,027; 3,399,952; 3,492,078; 3,556,709;
20 and 3,360,656.
The colored fiber generally contains about 0.01 - 2%
by weight dye (100% color basis).
Nickel-containing carpet printing with dyes of the formula (I) show excellent fastness properties. The fabric is colored with strong, bright blackish shades which are exceptionally fast to light, dry cleaning, crocking, gas and heat.
The invention may be better understood by referring to the working examples set forth below. In the working examples, the properties of dyed or printed polypropylene were evaluated according to the following tests:

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?~1 :, '~ ' 1~779Z8 Test No. 1: (Crocking) A crock test on an air driedprinted or dyed material conducted in accordance with AATCC Test Method 8-1972, page 112 of the 1974 Technical Manual of AATCC.
Test No. 2: (Heat stability) A heat stability test determined by subjecting an air dried sample to a heat treatment of 250F for 20 minutes. The heat treated sample is compared to an air dried sample with respect to shade change.
Test No. 3: (Crocking) The sample from Test No. 2 . . .
is tested for crocking according to the procedure of Test No. 1.

There should be no change in crocking.

Test No. 4: (Light fastness) A practical strength of a dyed or printed sample is exposed to a Xenon arc lamp (AATCC Test Method 16E-1974, page 133 of the 1974 Technical Manual of the AATCC). 3L4 to 4L4 exposures are the lower limit of desirability in the carpet trade.

Test No. 5: (Dry cleaning) An air dried sample is tested for color fastness to dry cleaning in accordance with AA'r~ T~?st M~thod No 132-1973. I~acle 117 of the 1974 Technical 1(~779Z8 su]furic acid. The mass was stirred at -5C for 2 hours. The cold diazo mixture was then added in a thin stream to a cold mixture of 16.6 g 2,4-dihydroxypropiophenone, 120 g propionic acid:acetic acid (1:5 by weight~, 2 g Tween 20* and 10 ml 20%
sulfamic acid solution. The coupling mass was stirred to room temperature overnight. The mixture was filtered and the cake was washed neutral with water.

.:.
Yield: 22.2 g Theory: 32.7 g 20g of the above product was charged to a sandmill with 30 g Lignosol FTA (ligninsulfonic acid dispersant) and 150 ml water.
The mixture was sandmilled until dispersion test was satisfactory.
Yield: 200 g 10% C~l~r Content Paste B. Dyeing of a Nickel-containing Polypropylene from a Dyebath.

Piece goods of "HERCULON" isotactic polypropylene containing a bis(p-alkylphenol)monosulfide nickel compound in the amount of about 0.12% calculated as metallic nickel by weight based on the weight of the polypropylene, were placed in a bath set at 35C
containing 1% Triton X-100* (iso-octylphenyl-poly-ethoxyethanol) based on weight of fiber, 1.0 - 1.5% acetic acid (pH 3-4) and 1.0% (based on weight of fiber) dispersion of the dye from (A).
After 5 minutes the temperature was raised to 95C over a 30 minute period. The dyeing was continued at 95C for an additional 45 minutes. The piece goods were removed from the dye bath, rinsed and soaped in 0.5% soap solution at 90C for 10 minutes.
The dyed fabrics were rinsed with water and dried.
The dyed fabrics were colored a bright navy shade when dyed at 0.5% having outstanding light fastness and excellent resistance ! ' to crocking, dry cleaning solvents and gas fading. In addition, the dyed fabrics did not show any color change in shade after heat ''','''.' * (-a reg~stered trademark) ~, a.l :, . . .

11:)77928 treatment. When dyed at 2%, the fabrics were colored a deep black of similar outstanding fastness properties.

C. Dyeing of a Nickel-containing Polypropylene with a Printing Paste.

A printing paste was prepared with 1000 parts of Tragacanth gum thickener (polysaccharides of galactose, fructose, xylose and arabinose with glucuronic acid), 5 parts acetic acid and a quantity of dispersed dye corresponding to 5 to 10 parts of a pure dye obtained in (A). A fabric made of fibers of polypropylene containing nickel (Herculon Type 40) was printed on a roller.
The fabric was dried and steamed for 8 minutes at 105 - 110C.
The fabric was vigorously washed in a bath of soap at 90C. The printed fabrics were colored bright navy to deep black shades of fastness properties similar to those obtained in (B).

EXAMPLE II
To prepare the azo compound .' 0~

O2N ~ ~C-N=N ~ H

O

(M.W. 372) . if instead of the 2-aminobenzothiazole in Example I, an equivalent ,.
amount of 6-nitro-2-aminobenzothiazole was used, the above azo ^-~ compound was obtained in 82% of the theoretical yield. When dispersed and applied to commercially available nickel-containing polypropylene fabrics, it produced bright greenish navy to black shades of excellent all-around fastness properties.

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1(~77928 EXAMPLE III
To prepare the azo compound OH

(~ ~C--N=11~ OH

(M.W. 375) a mixture of 16.5 g 2-aminobenzothiazole in 230 g 85% phosphoric - acid was stirred to 65C to complete solution. The mixture was then cooled to -5C, and there was added 40 g 40% nitrosyl - sulfuric acid. The mass was stirred at -5C for 2 hours. The : cold diazo mixture was then added in a thin stream to a chilled mixture of 23.5 g 2,4-dihydroxybenzophenone, 150 g propionic acid:acetic acid 1:5, 30 ml dimethylformamide, 2g Tween 20 and 10 ml 20~ sulfamic acid solution. The coupling mass was stirred to room temperature overnight. The mix~ure was filtered and ; the cake was washed neutral with water.
Yield: 36.6 g Theory: 41.2 g ~ The dispersed product dyed nickel-containing polypropylene fabrics ; in brownish black shades of excellent light fastness and ~ outstanding resistance to crocking and dry cleaning solvents.
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`!.: EXAMPLE IV

~ 20 To prepare the azo compound ~Ns ~ ~
; O2N IC-CH3 '' O

(M.W. 308) . . .

.., , , I

.;, . .

~(~779Z~

a total of 14.5 g 5-nitro-2-aminothiazole was diazotized by the procedure described in Example I. The cold diazo solution was added in a thin stream to a chilled mixture of 15.2 g 2,4-; dihydroxyacetophenone, 120 g propionic acid:acetic acid 1:5, 2 g Tween 20 and 10 ml 20~ sulfamic acid solution. After coupling was complete, the mixture was filtered and the cake was washed neutral with water.
Yield: 24 ~ Theory: 30.8 g The dispersed product dyed nickel-containing polypropylene fabrics in deep greyish black shades of excellent general fastness properties.

EXAMPLES V - XXVI
Table I shows further azo compounds which may be prepared according to the procedures of Examples I - IV and which will dye nickel-containing polypropylene fabrics in navy to deep black shades of excellent general fastness properties.

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TABLE I

_ _ ____ Example AZO COMPOUND

OH

H5C2~ ~C-N=N~OH

~--CH2 CH 3 _ ~ =N~OH

VII 5 2 C--U=U~-CH3 .. ~ 1 , ., ~ ; ~ )r">

r . .. . .. .
~. I
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` :~

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~0779Z~
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TABLE I (Continued) . _ ..
Example AZO COMPOUND

,~ ~

11 C~ /
o . -OH
. X F3C ~9/ N N~ OH

.: C~12CH3 ,~', O

, .. .
, ` ~ XI N OEI

:
. _ _ ' OH

X I I L ~ ~- C H 3 ,' O

.
:
.''~'-' . - 15 -.,."

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~077~Z8 TABLE I ( Con t i nu e d ) _ Examp 1 e AZO COMPOUND

XII I ~ 3C~ N ll J~ /C--N=N~OH
H3C ~ CH3 Cl XIV ~ N N~U

_ _ XV ¦ ~C-N N~/H

. ~ 2 3 : O
, :
", .; OH
~/C-N=N~ OH

.~., C-C3H7 (n ) . ~, O
.~: .
.,.. , _ . .

. ~

.~
~,.~,., . f~
~,1 , .. - :

,~' , ~ :
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1C~779Z8 TABI,E I (Continued) Example AZO COMPOUND

XV I I H 3C ~ C--~I=N ~OH

_' ~; OCI H3 OH
XVIII 2~ C-N=N~ OH
ICl--CH 3 . . O
, - - .

XIX ; ~ C-N=N ~ OH

,. _ __ _ _ _ ;'.', XX ¦ J~ C-~=N ~ OH
, .,. ICI - C 2H 5 : . O
,, _ '~

,, ., .-- ~ .
''~

, ln77sz8 TABLE I (Continued) Example AZO COMPOUND
. _ ; OH
XXI ~N3C--~--NN ~ OH

O

XXI I ¦ ~ C-N=N- ~ OH

~,, XXIII IX /C-N=N~ OH

. C-CH 3 ,.. ~ O

XXIV ~ C--N=N~ ~ ON

" C-C H (n) ~: 1l 3 7 O
.

.; - 18 -: ~J`

1~7~9~

TABLE I (Continued) Example AZO COMPOUND
,~ _ X~V ~ ~5/

~ 2 5 O
.' .
. . O

~ XXVI ¦O ~ /C-N=N~ ~ OH

. _ ~ ~

- Although the invention has been described in conjunction ,~ with the foregoing examples, it is not to be limited thereto, but ` instead includes all those embodiments within the scope and .: spirit of the appended claims.

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Claims (7)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A compound of the formula:
wherein A is or where R6 and R7 are independently selected from hydrogen; cyano; nitro; chlorine; bromine; lower alkyl;
lower alkylsulfonyl; trifluoromethyl; R'OOC-, where R' is lower alkyl; or phenyl; and R8 and R9 are independently selected from hydrogen, lower alkyl, lower alkoxy, chlorine, bromine, nitro, sulfamyl, N,N-(dilower alkyl)-sulfamyl, cyano and lower alkyl sulfonyl; and R is lower alkyl, benzyl or phenyl which is unsub-stituted or substituted with up to two substituents independently selected from lower alkyl, lower alkoxy, chlorine and bromine.

2. The dye of Claim 1, .

3. The dye of Claim 1, .

4. The dye of Claim 1, .

5. The dye of Claim 1, .

6. The dye of Claim 1, .

7. Metallized polyolefin dyed with a dye of the formula:
wherein A and R are as defined in Claim 1.