Compositions: coating or plastic – Materials or ingredients – Pigment – filler – or aggregate compositions – e.g. – stone,...
Reexamination Certificate
1999-11-15
2001-09-25
Green, Anthony (Department: 1755)
Compositions: coating or plastic
Materials or ingredients
Pigment, filler, or aggregate compositions, e.g., stone,...
C106S031780, C106S031790, C106S493000, C106S494000, C524S106000
Reexamination Certificate
active
06294012
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a novel laked azo pigment, processes for its preparation and to coating, plastic and ink compositions containing the pigment.
2. Description of Related Art
Metal salts of individual azo compounds containing a pyrazolone moiety containing one or two acid groups are known in the art as pigments. Azo yellow pigments are a class of colorants that are tinctorially strong and relatively inexpensive. Monoazo yellow pigments exhibit good lightfastness and are useful as coloring agents for paints and some printing inks. In plastics, however, monoazo yellow pigments tend to undesirably bloom and discolor at high temperatures, so their use is disfavored.
For example, German Patent 2,616,981 describes metal salts of pyrazolone azo dyes which are obtained by coupling diazotized 2-amino-4, 5-dichlorobenzene-l-sulfonic acid with 1-(sulfoaryl)-3-methyl-5-pyrazolone compounds and subsequent laking with metal salts.
Japanese Patent 62,166,359 describes electrophotographic toners that contain monoazo pigments of the formula
X=Cl or SO
3
−
; m=1 or 2; M=Mg, Ca or Ba; n=1 or 2. When X is Cl, then m is 1 and n is 2, and when X is SO
3
−
, then m is 2 and n is 1.
U.S. Pat. No. 4,594,411 describes
wherein R is CH
3
or COO
−
; X is Cl, CH
3
, CH
3
O, C
2
H
5
O C
2
H
5
CONH, NH
2
CONH, C
6
H
5
CONH, CH
3
SO
2
NH, CH
3
CONH, or hydrogen; Y is hydrogen, Cl, or CH3; Z is hydrogen or Cl, n is 0, 1 or 2; Me
+
is one equivalent of a cation selected from the group consisting of NH
4
+
, Li
+
, K
+
, Na
+
, ½ Sr
2+
, ½ Mn
2+
, ½ Ni
2+
, ½ Ba
2+
, ½ Mg
2+
and ½ Ca
2+
; with the provision that if R is COO
−
, the additional equivalent charge is compensated by a further equivalent of said or another cation.
wherein D is tri or tetrasubstituted phenyl ring; R is CH
3
or COO
−
; X is Cl, Br, CH
3
, CH
3
O, C
2
H
5
O CH
3
CONH, SO
2
NH
2
, SO
3
−
; Y is Cl, Br, CH
3
or SO
3
−
; Z is Cl, Br or CH
3
.
U.S. Pat. No. 5,047,517 relates to a yellow monoazo pigment which is obtained by diazotization of 2-amino-4-chloro-5-methylbenzene-1-sulfonic acid, coupling of the diazonium compound with 1-(3′-sulfophenyl)-3-methyl-5-pyrazolone and subsequent laking of the coupling product to the calcium salt.
U.S. Pat. No. 5,669,967 relates to a yellow monoazo pigment which is obtained by diazotization of 2-amino-5-chloro-4-methylbenzene-1-sulfonic acid, coupling of the diazonium compound with 1-(2′-chlorophenyl)-3-methyl-5-pyrazolone and subsequent laking of the coupling product to a divalent metal salt.
There is a desire, however, to obtain migration resistant yellow pigments with high heat stability and ease of preparation as well as reduced cost. There is also a need for these yellow pigments to show improved performance in one or more of the following properties: color strength, resistance to polar solvents and lightfastness.
SUMMARY OF THE INVENTION
This invention relates to an azo pigment suitable for use as coloring agent and processes for its preparation. The yellow azo pigment of the present invention is characterized by having both high color strength and high heat stability. The yellow azo pigment of the present invention is also characterized by having one or more of migration resistance to polar solvents, ease of preparation, low cost of preparation, and lightfastness.
In one embodiment, the present invention relates to a yellow pigment characterized by the formula:
In another embodiment, the present invention relates to a pigment composition containing two or more compounds wherein one of the compounds is represented by the formula:
In yet another embodiment, the present invention relates to a process for preparing a yellow pigment composition which involves making an azo dye by coupling (i) a diazonium component comprised of one or more aromatic amines wherein at least one of said amines is anthranilic acid characterized by the formula:
and salts thereof; with (ii) at least one coupling component characterized by the formula:
and salts thereof and metallizing said dye with strontium.
In still yet another embodiment, the present invention relates to coating, plastic and ink compositions containing the azo pigment compositions.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention provides azo pigments and processes for their preparation. The pigments of the present invention may be prepared by initially diazotizing one or more aromatic amines wherein at least one of said amines is anthranilic acid, coupling the diazonium component with 1-(3′-sulfophenyl)-3-methyl-5-pyrazolone coupler to form the desired dye, and laking the coupling product to the strontium salt.
Anthranilic acid or 2-aminobenzoic acid is characterized by the formula:
and salts thereof. Examples of preferred salts include ammonium and the alkali metal salts such as the sodium and potassium salts.
In one embodiment, mixtures of two or more aromatic amines, wherein one of the amines is anthranilic acid, are diazotized, then coupled with 1-(3′-sulfophenyl)-3-methyl-5-pyrazolone coupler, and laked to the strontium salt. In this embodiment, aromatic amines that are not anthranilic acid are supplemental aromatic amines. Such supplemental aromatic amines can be useful for shade adjustments of the pigments of the present invention.
A variety of suitable supplemental aromatic amines can be mixed with anthranilic acid for the purposes of the present invention. In one embodiment, the supplemental aromatic amines include primary aromatic amines wherein the aromatic moiety of the amines contains at least one substituent acid group or salts thereof, and preferably the alkali metal or ammonium salts of such supplemental aromatic amines. The aromatic amines may be monoamines or polyamines containing up to about four or more amine groups per molecule. Thus, the diazonium components derived from such supplemental aromatic amines may contain one diazonium group (mono-diazonium), two diazonium groups (bis-diazonium), three diazonium groups (tris-diazonium), etc. The supplemental aromatic aromatic amines may be monocyclic amines such as aniline and its derivatives, or bicyclic amines such as naphthyl amines and their derivatives. The supplemental aromatic aromatic amines may also be biphenylamines or polyamines such as aminobiphenyl, benzidine, and 3, 3′, 4, 4′-biphenyltetramine.
In another embodiment, the supplemental aromatic aromatic amine is a primary aromatic amine characterized by the formula
wherein each R is independently a halogen, hydrocarbyl, hydrocarbyloxy, carboxylic acid ester, sulfonic acid ester, carboxylic acid amide, imidazolone, sulfonic acid amide or nitro group; n is 0, 1 or 2; each Z is independently a —COOH or —SO
3
H group, or salts of such groups; m is 1 or 2; wherein it is understood that the imidazalone group is represented by the formula —NH—C—NH— which, when taken together with the aromatic ring, the nitrogen atoms are bonded to adjacent carbons to form a five member ring, and Formula IV is not anthranilic acid. The term “hydrocarbyl” as used in this specification and claims is intended to include hydrocarbons which may contain heteroatom containing substituent groups such as ether, ester, hydroxy, nitro or halogen which do not materially affect the hydrocarbon character of the group. The hydrocarbyl and hydrocarbyloxy groups typically contain from 1 to about 20 carbon atoms.
In another embodiment, the supplemental aromatic amines characterized by Formula IV contain 0, 1 or 2 R groups which are each independently a halogen, hydrocarbyl, hydrocarbyloxy, carboxylic acid ester, sulfonic acid ester, carboxylic acid amide, imidazolone, sulfonic acid amide or nitro group. The halogen group can be any of the halogens, although chlorine and bromine are generally used, with chlorine being the most preferred example of a halogen substituent. The hydrocarbyl
Engelhard Corporation
Green Anthony
Keller Raymond F.
LandOfFree
High strength monoazo yellow pigment does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with High strength monoazo yellow pigment, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and High strength monoazo yellow pigment will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2515125