USRE23304E - Manufacture of copper phthalocy - Google Patents

Description

Reiuuecl Dec. 12, 1950 MANUFACTURE OF COPPER PHTHAIDCY- ANINE DYESTUFFS Grady M. ONeal, Chicago, 111., assignor to The Sherwin-Williams Company, Cleveland, Ohio,

a corporation of Ohio No Drawing. Original No. 2,410,301, dated tober 29, 1940, Serial No. 502,506, September 15, 1943. Application for reissue October 29, 1947,

Serial No. 782.960

40 Claims. (Cl. 260-3145) The present invention relates to improvements in the manufacture of copper phthalocyanine dyestuffs. Such dyestuffs, due to their pure blue hue and excellent fastness to light, heat, water, mild acids and alkalies, are generally acknowledged to constitute one of the most important developments ever made in-the dye and pigment industries and, at least, the most important since the work in 1914 on precipitated basic dyestuffs.

Phthalocyanine is a generic term for a class of blue to green dyestuffs and the following formula has been proposed for the metal-free phthalocyanine parent substance:

It may be systematically designated as either tetrabenzoporphyrazine or as tetra-benzo-tetraaza-porphin.

Because of the economics and the difliculties connected with securing the intermediates used in preparing the parent and derivative substances, for example, o-cyanobenzamide or phthalonitrile, it has been proposed to employ other simpler and more readily available initial starting materials. Processes have been offered in which a carbocyclic anhydride, imide, or diamide is reacted with ammonia and metallic substances, thereby, under appropriate conditions, resulting in metallic phthalocyanine color formation. Processes making use of this method of synthesis, in general, are subject to these serious objections: poor yields are almost invariably obtained; great operational difliculties are present; and the resultant dyestuff is of poor quality due at least in part to the necessary high operating temperatures needed to effect color formation.

Other processes, notably those covered in U. S. Patents Nos. 2,216,761, 2,216,867, and 2,216,868, and likewise directed towards a simplification of the process for phthalocyanine dyestuff manufacture have been proposed, using aminosulphonic acid type compounds, with which certain dehydration and deammonation products [fdehydration" and "deammonation" indicating the removal, elimination, or loss of unit quantities of water and ammonia] of diammonium phthalate, for instance, phthalic anhydride, phthalimide, phthaldiamide, and the like, are reacted with a metallic reagent. In general, along with other objections, the temperatures necessary to effect dyestuff formation are high and the quality of the obtained dyestuffs is poor.

It has further been proposed in Fr. Patent No. 826,017 to react a phthalic acid derivative, dicyandiamide, and a metal-bearing reagent under special conditions to give the metallic phthalo cyanine. However, the yields of dyestuff by this process are extremely poor; the operating temperatures are high, giving poor quality dyestuffs; andl still worse, the reaction of dicyandiamide with phthalic acid derivatives is a highly exothermic one, oftentimes proceeding with ex treme violence.

Still other processes, as exemplified in U. S. Patents Nos. 2,197,458 [British Specification 464; 126], 2,197,459, and 2,214,477 [British Specification 476,243], have been proposed, using urea with which certain dehydration and deammonation products of diammonium phthalate, for instance, phthalic anhydride, phthalamide, phthaldiamide and the like, and a metallic reagent are suitably reacted. This proposed process pas ses'ses high merit, but it has the disadvantage that the process is accompanied by undesirable foaming and frothing of the reaction melt. Due to the nature and volume of these foams, the reaction mass cannot be kept at the necessary temperature of reaction. Consequently, processes making use of the urea method" of synthesis commonl yield a relatively low amount of the desired dyestui'f; processing equipment is unduly large with respect to the actual quantity of, material processed; and a certain amount of danger to the operating personnel is always present.

Hoyer et al., in U. 8. Alien Property Custodian application, Serial No. 403,866, have proposed that the disadvantages inherent with the "urea process for phthalocyanine dyestuff formation could be overcome by effecting the urea process" in the presence of auxiliary agents such as aromatic carboxylic acids or sulfonic acids or the amides thereof, these agents not being capable of conversion into phthalocyanines. This proposal has has numerous disadvantages among which are: it is economically wasteful due to the excessive amounts of auxiliary agent required; and it is specific only to phthalocyanlne-forming starting materials that contain sulfonic acid groups or cases earboxylgroupsinadditiontothecarboxylscid groups that take part in the phthalocyanine colorforming reaction.

From the foregoing state of the art it is apparent that, despite the intensive and ingenious eflorts since the pigmentary properties of copper phthalocyanine were first observed at the Grangemouth Works of Memrs. Scottish Dyes, Ltd. in 1938,thearthasasyeti'ailedtoachievea phthalocyanine dyestui! process which successfully combines the desiderata of high yield, optimum economy of starting materials, simplicity and ease of operation, safety, and quality. It is an object of this invention to obtain a combination of such advantages by providing a simple, practical, economic, and novel process for manufacturing copper phthalocyanines from a variety of substituted and unsubstituted benzene orthodicarboxylic acid compounds or certain of their dehydrated and/or deammonated products which, structurally, may be derived therefrom.

It is a particular object of this invention to form copper phthalocyanine dyestuffs by reacting the said substituted and unsubstituted benzene ortho-dicarboxylic acid compounds, or their said derivatives, with biuret and a copper-yielding compound. a

A further object of the invention is to accomplish the reaction of the said substituted and unsubstituted benzene ortho-dicarboxylic acid compounds, or their said derivatives, with biuret and a copper-yielding compound in the presence of an auxiliary agent.

A still further object of the invention is to eifect formation of the copper phthalocyanine dyestuffs without the excessive foaming and frothing peculiar to other processes of the prior art Various other ancillary objects and advantages will appear from the following detailed description and explanation of the invention.

These objects may be'accomplished by reacting, in the presence of a catalytic auxiliary agent, biuret, a copper-yielding compound and an ortho aromatic compound of a group having a generic formula:

cooNm \COONH| minus :cHsO, minus IINHJ- R is a benzene nucleus and may contain various substituents such as halogen, nitro, amino, aryl, alkyl, aryloxy, alkoxy, sulfo, carboxyl, sulfonvl, benzoyl, and the like (these substituents may appear more than once and they may be in combination); a: is an integer which may vary from through 3; 1! is an integer which may vary from 0 through 2, but the sum of :r and 11 does not exceed 3.

The copper phthalocyanine dyestufls that may be prepared according to this invention may be expressed by this generic formula wherein R consists of a benzene nucleus which may possess the substituents enumerated hereinabove a of present work. when a suitable catalytic auxiliary agent and a sufilcient proportion (with respect to the aromatic compound) or biuret is present, the aromatic compound first reacts with the biuret to form an addition product. This addition product, as a result of heat, then undergoes a dehydration, deammonation, and decomposition in the presence of the auxiliary agent and a ccpper-yieding compound to give the desired dyestufl' formation. This may not be, however, the correct or entire explanation.

Biuret, also known as allophanamide, may be considered as one of the many derivatives of urea, more particularly, a deammonation product obtained in small amounts by decomposition and condensation when urea is heated slowly under atmospheric pressure between temperatures of a fairly specific range. One of the fundamental differences between biuret and its parent substance, in so far as expected chemical reactivity is concerned, is that urea, as is well known, is a substantially neutral, if not slightly alkaline, substance, while biuret possesses acid properties. See "The Nitrogen System of Compounds"- Franklin. Pp. 114 and 118 (1935). While biuret may be obtained from urea by a mere heating, its preparation is best performed by conducting the urea transformation under special conditions, cf., U. S. Patent No. 2,145,392 or Vaninos Praparative ChemieOrganischer Tell," p. 221 (1937). This is done because the amount of biuret formed from heat transformation or urea at atmospheric pressure is very small due to the fact, that as the temperature is raised or the heating prolonged in order to convert more of the urea, formation of an increasing amount of by-products, such as ammelide and cyanuric acid, occurs and the yield of biuret remains quite low. To illustrate: heating of urea at 147-152 C. for nine hours gives a yield of biuret (anhydrous basis) of only 12.0%; and heating at 147-152 C. for forty-three hours gives a yield of only 13.1%.

Likewise, biuret, when heated slightly above its melting point (192-3" 0.), say at 200 C. for one hour, is completely decomposed, giving waterinsoiuble and gaseous products and a small quantity of material melting at 103-106 C. [cf.,

Langes Handbook of Chemistry," 4th edition (1941), DD. 302-3].

It is well known that phthalic anhydride and urea react together to give the monoureide at 118-124 0., [cf. Piutti, Liebigs Annalen der Chemie," 1882, 214, pp. 17-30]. Further, the interaction of phthalic anhydride and urea to give phthalimide according to the equation:

' atmospheric heating of urea to reaction ternperatures prior to introduction of phthalic anhydride [cf. U. 3. Patent 2,214,477] will not produce a sufiicient proportion of biuret; separate heating of urea at a temperature in excess of the melting point of biuret [cf. U. S. Patent 2,197,458] will decompose such incidental amounts of biuret which may be formed. Other urea derivatives, notably formamide, dicyandiamide, ammonium carbonate, ammonium carbamate, guanylurea, guanidine, thiourea, carbonyl urea, monosodium urea, methylol urea, ammelin, ammelide, cyanuric acid, and cyanamide, have been reacted with phthalic anhydride in accordance with the procedure of the present invention. These urea derivatives either give no dyestuff formation, or a product that is worthless.

In perfecting the present invention, it has been found that the interaction of the described substituted or unsubstituted benzene ortho-dicar boxylic acid compounds or their derivaties, with biuret and the copper-yielding compound proceeds with poor yields of dyestuff, even when the operating temperatures are either low, as at 185-200 C., or high, as at around 250-275 C. It is only through the use of various catalytic auxiliary materials that dyestufi formation proceeds at comparatively low temperatures in high yields and with good quality. These auxiliary agents are specific in nature and only a few seem effectively to assist in the dyestuff formation. Their exact role is unknown. Of some value are those agents containing the elements: antimony, tung sten, selenium, and boron; and of particular value are those agents containing the elements: molybdenum, arsenic, and vanadium. These elements are all characterized by having acid oxides. effectiveness and variations of various elements in favoring copper phthalocyanine dyestuff formation may be viewed in the light of subsequent Table I. The auxiliary agents functioning in the process of the present invention include salts, oxides, acids, and inorganic and organic complexes. Two or more elements may exist in a compound functioning as an auxiliary agent, for example, a vanado-molybdic acid.

The quantity of auxiliary agent present in the reaction mass may vary, indicating its functioning in the nature of a catalyst. Small quantities in terms of the total reaction mass have a very marked and pronounced effect. Even with as low as 0.08% in terms of the weight of the reaction mass, favorable action in lowering the formative color reaction temperature is observed, as well as an increased yield of the resulting copper phthalocyanine dyestuif. When the quantity of auxiliary agent is increased much beyond 2%, very little adde benefit obtains. Therefore, hereinafter and in the appended claims the auxiliary agent is referred to as a catalyst.

By the process of the present invention, color formation has been observed at temperatures as low as 135l40 C. It is enerally preferred, however, for optimum results to carry out the reaction in the neighborhood of 175195 C. The preferred range is l60200 C. The reaction may be conducted at temperatures in excess of 200 C., and as high as 300 C., but with increased temperatures of reaction over about 200 C. the quality and yield of thejormed dyestufl' suffers, in part at least due to loss of biuret by decomposition.

Although the reagents for the reaction mass may be associated in a variety of ways, it is preferred that they be associated in stages, thus utilizing progressive synthesis. This preference gives a method of reacting to secure the desired features of economy, quality, and ease of manipulation.

The

The quantity of biuret employed in the present process may vary. as described hereinafter. the preferred range being between 1.5-2.0 moles of biuret per mole of ortho aromatic compound.

The copper phthalocyanines of the present invention are preferably made by reaction under exposure to the atmosphere. But they may also be prepared by heating the aromatic compound with the biuret, catalyst, and copper-yielding compound in a closed vessel under pressure.

As copper-yielding compounds it is preferred to use copper salts. Among those that have been used to advantage are the chlorides, bromides. acetates, and sulfates. Generally, these copper salts are most advantageously employed in the anhydrous state. The copper-yielding compounds may be any of those known in the art for making copper phthalocyanine dyestuif.

My invention may best be illustrated by reference to the following specific examples of its application to actual practice, although it is to be understood that they are given merely as illustrations and are not to be construed as limiting the scope of the invention. In the examples that follow, all parts are given by weight.

EXAMIPLEI 36.0 parts of biuret (M. P. 189-190 C.) are heated in a suitable vessel fitted with an agitator. When the internal temperature is at -140 C.. 30.0 parts of phthalic anhydride are added over a 25 minute period with the agitated mass being held within the 135-140 C. range. Then 0.06 part of ammonium molybdate, (NH4) sMo-1O24.4H:O, and 7.5 parts of anhydrous cuprlc chloride are added over a 10 minute period. The reaction mass at this point is a thick paste.

With continued agitation throughout the ensuing reaction period, the reaction temperature is raised during 1%; hours until an internal temperatureof 185-190 C. is reached. During this temperature rise, 0.5 part portions of biuret are added at approximately 2.7 minute intervals until a total of 14.0 parts has been added. The temperature rise and biuret additions are so adjusted that the mass is at all times a fairly viscous paste.

During the temperature rise from 135-140" C. the reaction mass becomes greener and darker. At -170 C. a coppery bronze appears and shortly thereafter, a dark reddish-blue coloration.

The mass is then held at l85-190 C. for two hours, and then cooled, and ground to a powder. The resulting powder is then extracted with 1,000 parts of a dilute aqueous solution of caustic soda, preferably a 2.5% solution by weight, by heating at the boiling temperature for 10 minutes. A filtration and washing with water to neutrality is then performed. A second extraction, this time with 1,000 parts of a 5% aqueous hydrochloric acid solution is now performed in the mannerbf the caustic soda treatment. This is similarly followed by a filtration and water washing to neutrality of the filter cake. The neutral filter cake is then dried, giving a yield of 23.6 parts of a copper phthalocyanine. This corresponds to a yield of 76.2% of theory, based on the phthalic anhydride and considering the product as a monochlorinated copper phthalocyanine.

The said copper phthalocyanine crude may then be conditioned for use as a pigment in one of many known ways, preferably that of my copending application, Serial No. 381,396, filed March 1. 1941. U. S. Patent 2,367,519. The con- 7 ditioiied pigment has excellent quality and high tinctorial value.

EXAMPLE 2 In a preparation similar to that of Example 1, a molecular equivalent of anhydrous cupric bromide is employed as the copper-yielding materiai. The obtained copper phthalocyanine re-' sembles the copper phthalocyanine of Example 1, in properties. and is thought to contain a brominated form. It is obtained in the amount of 24.5 parts and pigmentary properties of a high order.

EXAMPLE 3 51.4 parts of a commercial biuret having by analysis a composition given as follows: 70-75% biuret, 15-20% cyanuric acid, and 10% ammelide, are around and mixed with 30.0 parts of phthalic anhydride, 0.06 part of ammonium molybdate and 7.5 parts 01' anhydrous cupric chloride. The resulting powdery mass is placed into a suitable vessel and, with agitation, the temperature is raised over a /4 hour period until an internal temperature of 185-190 C. is attained. A two hour reaction period at this temperature is maintained with stirring throughout the period. At the end of this time the reaction mass is worked up in the manner of Example 1 to give 18.0'parts' of copper phthalocyanine.

During the reaction period the mass is a heavy paste and no frothing or foaming occurs. This example illustrates a somewhat different procedural method, as well as a variation in the composition of the active biuret ingredient.

EXAMPLE 4 36.0 parts i biuret (M. P. 189-190 C.) are placed into a suitable reaction vessel fitted with an agitator. Agitation is carried on throughout the reaction period. The temperature of the biuret is raised to 160-165 C., then 30.0 parts of phthalic anhydride are added over a 30-40 minute period within the 160-165 C. range. Then 0.06 part of ammonium molybdate and 8.9 parts action temperature raised over a 80 minute period until an internal temperature of 180-185 C. is reached. Three hours heating follows at this temperature. The resulting color mass is then processed. as in Example 1, giving 18.6 parts of copper phthalocyanine. The obtained dyestufl es excellent pismentary properties and is redder in shade than the copper phthalocyanine of Example 1.

EXAMPLE 5 By substituting a molecular equivalent of anhydrous cupric acetate for the cupric sulphate of Example 4, copper phthalocyanine can be obtained in likewise good yield.

EXADIPLESG,7,8,AND9

Further examples and results are shown in Examples 6, 7, 8, and 9. In these the phthalic anhydride is replaced by a chemical equivalent of benzene ortho-dicarboxylic acid or a derivative of it, and likewise the copper salt is an anhydrous equivalent where different.

Parts Yield Ex- Employed Ortho-Dicar- Em loyed Copperof Pbthalample boxylic Acid Compound YieIding Material ocyanine Dyestuii 6 phthalic acid cupric sulfate 16. 0

7 phthollmide ..do 17. 4

9 dlammonium phthalate.-. cupric chloride-.-. 12. 1

Table I Parts 5 51*? 04mm; E

a 7: o Item Catalyst 'gg f g 3%,! in Terms Periodic tracked Y5 10M of Bear, Group I (Jogger P tlon Mass PM 10- 1 Nona 1.2 (NH4)lM010n-4H|0 0. 0o 0. 08 VI 1). e 0 l. 47 2. 0 VI 21. 7 3. 68 5. 0 VI 21. G 1. 47 2. 0 VI 21. B 1. 47 2. 0 VI 21. 9 Silica-molybdic acid..-" 1. 47 2. 0 VI 21. 2 Ammonium metavanadate l. 47 2. 0 V 15. 0 Arsenous oxide 1. 47 2.0 V 11. 8 Antimony trloxide- 1. 47 2. 0 V 7. 0 Doric Acid. 1. 47 2. 0 III 7. 0 Zinc Oxide"--- 1.47 2.0 II 1.2 1. 47 2. 0 II 2. 6 1. 47 2. 0 III 3. 4 1. 47 2. 0 IV 1. 1 1. 47 2.0 IV 1. 0 1. 47 2. 0 IV 1. 2 1. 47 2. 0 IV 2. 4 H120: v 1. 47 2. 0 V 2. 2 (NHOiHPOi. O. 48 0. V 3. 4 HOsSsOl. 1. 47 2. 0 VI 0. B 1. 47 2. 0 VI 4. 9 1. 47 2. 0 VI 3. 1 1. 47 2. 0 VI 5. 0 1- 47 2. 0 VII 0. 7 1. 47 2. 0 VII 2. 9 1. 47 2. 0 VIII 1. 5

of anhydrous cupric sulfate are added over a 20 minute period. The reaction mass. at this point a fairly liquid we. enema and the re- It is seen, therefore, from the data of Table I that the interaction of biuret, phthalic anhydride and the copper-yieldin material. without the 9 catalyst, is of little value for all practical purposes. n the other hand, when certain specific catalysts are employed, useful yields of copper phthalocyanine result.

It has been mentioned hereinabove that the aromatic compound may have other substituents present in the benzene nucleus besides the hydrogen illustrated in the preceding examples. Typical substituted benzene ortho-dicarboxylic acid compounds that may be employed in the process of the present invention are: 3,4 dimethyl phthalic acid, 4-chloro-phthalic acid, i-nitrophthalic acid, d-ethoxy-phthalic acid, 3-phenoxyphthalic acid, 4-acetamino phthalic acid, 4- phenyl-phthalic acid, N-benzenesulfonyl-a-amino-phthalic acid, and others. Likewise, these various substituted benzene ortho-dicarboxylie acids may be employed in the form of their anhydrides, imides, diamides, and the like. A typical example illustrating the use of a substituted derivative of benzene ortho-dicarboxylic acid in preparing copper phthalocyanine dyestuffs in accordance with the present invention follows:

EXAMPLE The procedure of Example 1 is repeated, except that the 30.0 parts of phthalic anhydride are replaced by 39.0 parts of 4-nitro-phthalimide (M. P. 197.5-l98 C.). The yield of dry copper tetra-nitro-phthalocyanine, after the extractions and washings, amounted to 34.5 parts or 89.9% of theory. It is a blue-green dyestuii.

It has been indicated earlier that the initial starting intermediates that are suitable for employment in my new and novel process are all related and may be regarded, for purposes of classification, as transformation products of a substituted or unsubstituted diammonium phthalate compound. In the foregoing examples, the use of phthalic anhydride, phthalic acid, phthalimide, phthaldiamide, and diammonium phthalate have been illustrated. Each of these color-forming compounds may be regarded as a transformation product of diammonium phthalate and precursor of phthalonitrile in terms of integer mole units of NH: and Thus, di ammonium phthalate and the" entire class of typically illustrated. Thus, it is to be understood in the following claims that the partly empirical formula CaHdCOONHs): minus 28:0. minm uNI-Ia represents the group consisting of the twelve ortho aromatic compounds tabulated above and that the formula R(COONH4):, minus ICHzO, minus yNI-h represents said compounds with or without one or more suitable substituents on the benzene nucleus.

transformation products which are applicable in the present invention may be tabulated as follows:

Table II [Transformation product-diammonium plithalate less 1 (H10) and y (NHQJ Product diamonium nhthalate monoammonium phthalate plitbalic acid phthaldiamide monoammonium o-cyano-benzoatc. phthalimide By examining the formulas above for the phthalocyanines, it is seen that theory calls for 4 benzene rings and 8 nitrogen atoms. Biuret contains 3 nitrogen atoms in one mole. Theoretically, then 2 moles of biuret are required for 3 moles Of phthalic anhydride, for example. Thus, 0.66 mole of biuret is the minimum reactive quantity, in theory, for 1 mole of phthalic anhydride, or its equivalent. In Example 1, 2 moles of biuret, and in Examples 3 and 4, approximately 1.5 moles of biuret are employed per mole of benzene nucleus. In addition there is a loss of ammonia in the reaction, in part from the reaction and in part from thermal decomposition. Some deficiency or excess of biuret with respect to the range of 0.66 mole to 2.0 moles may be employed without affecting the character of the reaction. although, of course, the yield of product will be affected. The present invention contemplates the use of relative quantities adjusted to and consistent with economy Of yield, raw material cost,

production time, and like factors.

It is intended to cover in the claims which follow all such extensions and variations as would naturally occur from the foregoing, to one skilled in the art.

What is claimed is:

l. The method of making a copper phthaiocyanine dyestuff which comprises reacting together at a temperature in the range from to 300 0.. and in proportions sufficient to produce copper phthalocyanine, biuret, an ortho compound having the formula: R(COON'H1) a. minus :cHzO, minus yNHa, and a copper-yielding compound, in the presence of a catalyst for the reaction, said formula being such that a: is an integer varying from 0 through 3, y is an integer varying from 0 through 2, both while x+y is not more than 3, and R is a benzene nucleus selected from the groupconsisting of the unsubstituted benzene nucleus and substituted benzene nuclei.

2. The method of claim 1 in which the catalyst is present in the quantityof 0.08 to 2% of the reaction mass.

3. The method of making a copper phthalocyanine dyestuif which comprises reacting together at a temperature in the range from to 200 0., and in proportions sufflcient to produce copper phthalocyanine, biuret, an ortho compound having the formula: R(COONH4) 2. minus :rHzO, minus yNH3, and a copper-yielding compound, in the presence of a catalyst for the reaction, said formula being'such that a: is an integer varying from 0 through 3, y is an integer varying from 0 through 2, both while zc+y is not more than 3, and R is a benzene nucleus selected from the group consisti'ing cf the unsubstituted benzene nucleus and substituted benzene nuclei.

4. The method of making a copper phthalocyanine dyestuff whichcomprises reacting together at a temperature in the range from 135 to 300 C. biuret, an ortho compound having the formula: R(C0ONH4) 2, minus zHaO, minus vNHa. and a copper-yielding compound. in the presence of a catalyst for the reaction, said biuret being present in the proportion of at least 0.66

11 mole per mole of'said ortho compound and said formula being such that a: is an integer varying from through 3, y is an integer varying from 0 through 2, both while -:|:+y is not more than 3, and R is a benzene nucleus selected from the group consisting of the unsubstituted benzene nucleus and substituted benzene nuclei.

5. The method of claim 4in which said copperyielding compound is a copper salt.

6. The method of claim 4 in which said copperyielding compound is a copper halide salt.

7. The method of claim 5 in which said copperylelding compound is a copper chloride.

8. The method of claim 5 in which said copperyielding compound is a copper acetate.

9. The method of claim 5 in which said copperyielding compound is a copper sulphate.

10. The method of claim 4 in which the catalyst contains molybdenum.

11. The method of'claim 4 in which the catalyst contains vanadium.

' 1-2.- The method of claim 4 in which the catalyst contains arsenic.

13. The method of making a copper phthalocyanine dyestufl which comprises reacting together at a temperature in the range from 160 to 200 C. biuret, an ortho compound having the formula: R(COONH4) a, minus :HaO, minus yNHa, and a copper-yielding compound. in the presence of a catalyst for the reaction, said biuret being present in the proportion of at least 0.66 mole per mole of said ortho compound and said formula being such that .1 is an integer varying from 0 through 3, u is an integer varying from 0 through 2. both while .1:+y is not more than 3, and R is a benzene nucleus selected from the group consisting of the unsubstituted benzene nucleus and substituted benzene nuclei.

14. The method of making a copper phthalocyanine dyestufl which comprises reacting together at a temperature in the range from 160 to 200 C. biuret. an ortho compound having the formula: R.(COONH4) 2. minus :rHzO. minus yNHz, and a copper-yielding compound, in the presence of a catalyst for the reaction, said biuret being present in the proportion varying from 0.66 to 2 moles per mole of said ortho compound and said fonnula being such that a: is an integer M ng from 0 through 3, 1 is an integer varying from 0 through 2. both while 1+ is not more than 3, and R is a benzene nucleus selected from the group consisting of the unsubstituted bensene nucleus and substituted benzene nuclei.

15. The method of claim 14 in which said copper-yielding compound is a copper salt.

16. The method of claim 14 in which said copper-yielding compound is copper chloride.

17. The method of claim 14 in which said copper-yielding compound is copper acetate.

16. The method of claim 14 in which said copper-yielding compound is copper sulphate.

19. The method of claim 14 in which the catalyst is present in the quantity from 0.08 to 2% of the reaction mass and contains molybdenum.

20. The method of claim 14 in which the catalyst is present in the quantity from 0.08 to 2% of the reaction mass and contains vanadium.

21. The method of claim 14 in which the catalyst is present in the quantity from 0.08 to 2% of the reaction mass and contains arsenic.

22. The method of making a copper phthalocyanine dyestuii' which comprises reacting together at a temperature in the range from 135' to 300 C.. and in proportions suiilcient to pro- 5 the reaction. said formula being such that s is an integer varying from 0 through 3. y is an integer varying from 0 through 2, both while z+y is not more than 3. 1

23. The method of making a copper phthalocyanine dyestuit which comprises reacting together at a temperature in the range from to 300 C.. biuret and an ortho compound having the formula: CsH4(COONH4)2. minus :HzO. minus vNI-h, and a copper-yielding compound 16 in the presence of a catalyst for the reaction.

said biuret being present in the proportion oi at least 0.66 mole per mole of said ortho compound and said formula being such that .1: is an integer varying from 0 through 3, 1! is an integer varying from 0 through 2, both while a:+u is not more than 3.

24. The method of claim 23 in which said copper-yielding compound is a copper salt.

25. The method of claim 23 in which said copper-yielding compound is copper chloride.

26. The method of claim 23 in which said copper-yielding compound is copper acetate.

27. The method of claim 23 in which said copper-yielding compound is copper sulphate.

28. The method of making a copper phthalocyanine dyestufl which comprises reacting together at a, temperature in the range from to 200 C., biuret and an ortho compound having the formula: CsH4(CQONH4)a, minus :HzO. minus :vNHJ, and a copper-yielding compound in the presence of a catalyst for the reaction. said biuret bein present in the proportion of at least 0.66 mole per mole of said ortho compound and said formula being such that a: is an integer varying from 0 through 3, 1! is an integer varying from 0 through 2. both while 2+1 is not more. than 3.

29. The method of claim 28 in which said catalyst is present in the quantity varying from molybdenum.

30. The method of claim 28 in which said catalyst is present in the quantity varying from 0.08 to 2% of the reaction mass and contains vanadium.

31. The method of claim 28 in which said catalyst is present in the quantity varying from 0.08 to 2% of the reaction mass and contains arsenic.

32. The method of making a copper phthalocyanine dyestuii which comprises reacting together, at a temperature in the range of 160 to 200 C. and in the presence of a catalyst for the reaction, phthalic anhydride. biuret present in the proportion of 0.66 to 2 moles per mole of phthalic anhydride. and a copper-yielding compound.

33. The method of making a copper phthalocyanine dyestufl which comprises reacting together, at a temperature in the range of 160 to 200 C. and in the presence of a catalyst for the reaction, phthalic acid, biuret present in the proportion of 0.66 to 2 moles per mole of phthalic 70 acid, and a copper-yielding compound.

34. The method of making a copper phthalocyanine dyestuii which comprises reacting together, at a temperature in the range of 160 to 200 C. and in the presence of a catalyst for the 7s reaction, phthalimide, biuret present in the pro- 0.08% to 2% of the reaction mass and contains 13 portior of 0.66 to 2 moles per mole of phthalimide, and a copper-yielding compound.

35. The method of making a copper phthalocyanine dyestufi which comprises reacting together at a reacting temperature above about 135 C., and in proportions sufficient to produce copper phthalocyanine, biuret, an ortho compound having the formula: R(COONH4):, minus :tHzO, minus yNHa, and a copper-yielding compound, in the presence of a catalyst for the reaction, said formula being such that a: is an integer varying from 0 through 3, y is an integer varying from 0 through 2, both while a:+x is not more than 3, and R is a benzene nucleus selected from the group consisting of the unsubstituted benzene nucleus and substituted benzene nuclei.

36. The method of making a copper phthalocyanine dyestuff which comprises reacting together within the temperature range between 135 C. and 200 C., and in proportions sufllcient to produce copper phthalocyanine, biuret, an ortho compound having the formula: R(COONH4)2, minus :cHzO, minus yNI-Iz, and a copper-yielding compound, in the presence 01' a catalyst for the reaction, said formula being such that a: is an integer varying from 0 through 3, y is an integer varying from 0 through 2, both 14 while az+y is not more than 3, and R. is a benzene nucleus selected from the group consisting oi the unsubstituted benzene nucleus and substituted benzene nuclei. 7

37. The method as claimed in claim 1 in which the reaction is carried out within the temperature range between about 200 C. and 300 C.

38. The method as claimed in claim 1 wherein the temperature of the mixed reacting compounds is raised to a reacting temperature not higher than about 300 C.

39. The method as claimed in claim 1 wherein the temperature of the mixed reacting compounds is raised to a reacting temperature not higher than about 200 C.

40. The method as claimed in claim 23 wherein the proportion of biuret is from about 1.5 to about 2.0 moles per mole of the ortho compound.

GRADY M. ONEAL.

REFERENCES CITED UNITED STATES PATENTS Name Date O'Neal Oct. 29, 1946 Number