US3525741A - Chlorinated stilbyl naphthotriazole brighteners - Google Patents

Description

E 19.70 R. ZWElDLER ETAL 3,525,741

CHLORINATED STILBYL NAPHTHOTRIAZOLE BRIGHTENERS Original FiledSept. 23, 1965 2 Sheets-Sheet :2

WHITENESS -TlME DIAGRAM N- t l CH =CH U) N y g I v NoSO CL l l I I I I i +5 +6 +4 +2 0 -2 -4 6 -e "7149/7/06 A whiteness (A H -H Rein/2am Zwe/d/er H Hunter Unit of which yellow hue no longer P0670 discernible in whilel96 on Hunfer Scale) X el r H White Effect Measured 1 (Hunter Units) United States Patent Office 3,525,741 Patented Aug. 25, 1970 3,525,741 CHLORINATED STILBYL NAPI-ITHOTRIAZOLE BRIGHTENERS Reinhard Zweidler, Basel, Rudolf Keller, Riehen, near Basel, and Max Keller, Riehen, Switzerland, assignors to Geigy Chemical Corporation, Greenburgh, N.Y., a corporation of Delaware Continuation of application Ser. No. 489,655, Sept. 23, 1965, which is a continuation-in-part of application Ser. No. 381,906, July 10, 1964. This application Nov. 21, 1967, Ser. No. 684,872 Claims priority, application Switzerland, July 9, 1964, 9,043/64 lint. Cl. C0711 55/02; Clld 9/44 US. Cl. 260-240 10 Claims ABSTRACT OF THE DISCLOSURE Certain new chlorinated mononaphtho triazolyl stilbenes are provided which are useful as optical brighteners and are particularly characterized by their exceptional stability in the presence of chlorine bleaches.

This application is a continuation of application; Ser. No. 489,655, filed Sept. 23, 1965, which was in turn a continuation-in-part of application Ser. No. 381,906, filed July 10, 1964. Both of said earlier applications are now abandoned.

This invention relates to new optical brighteners, and more particularly to new blue-fluorescent chlorinated mononaphthotriazoles which are substantive to and produce an improved whitening eifect on textile fiber mate rials, especially on cellulosic fibers such as cotton and on synthetic polyamide fibers such as nylonl.

It is well known that white textile material such as mens shirts, ladies white dresses, underwear, bed-linen and the like are given a whiter appearance by adding to the washing agents used for their cleaning certain amounts of optical brighteuers. Due to the fact that modern textile cellulosic materials, in particular cotton materials, are given increasing contents of textile finishes in the form of synthetic resins, for instance as anti-crease finish in dry state, and so-called non-resin finishes which yield so-called cross-linked cellulose as anti-crease finish in wet state, it is necessary to apply larger amounts of the aforesaid optical brighteners to such modern textile materials, than had been required in the past in order to achieve at least the same or preferably whiter whitening effect.

Blue fluorescing unchlorinated mono-naphthothiazolyl-stilbenes have been used as whitening agents in washing agents, detergents and washing liquors for the aforesaid textile materials free from active chlorine and also in such agents and liquors which contained a moderate amount of active chlorine.

However, in applying such increased amounts of brightening agents, particularly those of the mononaphthotriazolyl-stilbene series, to the modern textile materials, the latter often assume an undesirable greenish shade, which becomes more and more pronounced, the more particularly of cotton and nylon fabrics in a single containing these brightening agents.

At the same time, laundering of textile fibers and fabrics of cellulose and/or synthetic polyamide fibers, and more particularly of cotton and nylon fabrics in a single bath permitting simultaneous cleaning, whitening and bleaching is increasingly in demand.

Moreover, washing liquors and detergents for preparing them are now preferred which contain higher amounts of active chlorine than in the past, with a view of better sanitation, for example contents in the range of 0.5 to

0.6 gram per liter of active chlorine instead of the lower contents of 0.1 to 0.3 gram per liter preferred in wash liquors only a few years ago. Detergents and washing liquors prepared therefrom, that are to serve for cleaning, Whitening and bleaching at one and the same time, must therefore contain brightening agents which are stable at the high concentrations of active chlorine now required. In modern detergents of this type, the brightening agents should be stable for at least several weeks especially during long periods of storage even under adverse climatic conditions such as high temperatures in summer and high degrees of humidity. Active chlorine is suppled in the wash liquors from chlorine-releasing compounds contained, e.g., in the detergents, among which compounds sodium dichloroisocyanurate is especially preferred.

The best commercially used mono-naphthotriazolylstilbene brighteners which had shown very satisfactory fluorescence and also satisfactory build up with intensified White effect after repeated washings, failed to yield satisfactory results in the new detergents and liquors of higher chlorine content.

Moreover, when not used by industrial chemists but, for example, by a housewife, many of the previously known optical brightening agents having a basis of mononaphthotriazoyl-stilbene compounds have great disadvantages. Often the drawing power is insuflicient at the relatively low application temperatures to C.) preferred in such non-industrial applications. If certain commercial products having particular aflinity to the fibers are used under the lower temperature conditions described, spots due to bad levelling power occur on the treated goods. Also, the Water-solubility of products having the necessary afiinity to the fibers at higher temperatures is often too slight at low temperatures which also causes spots to appear on the treated materials.

It has now been found that the above-described severe and manifold demands made on optical brighteners under modern washing conditions are met satisfactorily and fully by novel compounds the free acid form of which is of the formulas Ho 3's and l Hoa n and, with the exception of a noticeable lower fluorescence effect on nylon, also by a novel compound the free acid form of which is of the formula (II-A) as well as the disulfonated analogs of Formulas II and II-A which possess a second -SO H group in 5- or 6-position at the naphthyl nucleus and particularly by the salts of these compounds with monovalent cations, especially alkali metal or ammonium ions.

The satisfactory whitening properties of these two CHEQA (III) shows a marked loss of fluorescence in wash liquors having higher contents (0.5 to 0.6 g. per liter) of active chlorine, known compounds obtained from the above compound III by introduction of one or two chlorine atoms into the benzene ring A'thereof which chlorinated compounds are designated by IV, V and VI in Table I below, show a marked decrease of fluorescence, compared with that of the chlorine-unsubstituted compound, especially on nylon fabrics laundered in wash liquors free from chlorine and containing the respective brightenings in amounts necessary for achieving equal degree of whiteness on cotton, as shown by fluorescence data given in Table I below, measured on a fluorometer of Type 240 manufactured by Schildknecht A. G., Zurich, Switzerland.

It is, therefore, very surprising that the 2,4-dichloroand especially the 3,4-dichloro-substituted compounds I and H, the data of which are also giveni in Table I below, show fluorescence effects on nylon which are in the same range (compound II) or even surpass (compound 1) those of the corresponding ring A-unsubstituted compound III and which are by more than 25% (compound II) and even 40% (compound 1) higher than the effect attained under the same conditions with a more than three-to-five-fold amount of the structurally closest re- Also in washings on cotton with wash liquors containing about 3.50 mg. per liter of brightener and about 0.6 gram per liter of active chlorine, fluorescence values achieved with compounds I and II are by 36% and 30%, respectively, higher than the fluorescence achieved under the same conditions with the 2,6-dichloro isomer V, while the fluorescence value of the latter is more than 18% below that of the ring A-unsubstituted analog HI.

Moreover, both compound I and compound H give commercial wash products, especially heavy-duty nonsoap detergents of the Tide and Syndet type, a whiter appearance more appealing to a significant proportion of the public similar to the whitening achieved with ring A- unsubstituted analog III and compound IV, monochlorinated in ortho-position, a fact which is especially unexpected since the para-monochloro derivative VI and the 2,6-dichloro compound V impart to the same wash powders pronounced discoloration.

A most unexpected superiority of the novel compounds of Formulas I, II and II-A and their salts and disulfonated analogs according to the invention is, however, shown in the stability of these novel compounds in nonsoap detergents containing chlorine-yielding agents, es-

pecially the above-mentioned sodium dichloroisocyanurate or similar suitable substances, mentioned further below.

This is illustrated in the accompanying drawing in which Diagrams I and II show the white etfects achieved on cotton with a non-soap detergent containing dichloroisocyanurate and one of the chlorine-substituted stilbene brighteners listed further below, after such detergent had been stored for 32 and 64 days, respectively.

Tested chlorinated stilbene brighteners are those falling under the formula:

namely the known compounds in which R represents and and the novel compounds according to the invention in which R represents:

white effects of which are given in Diagram I, and the disulfonated compounds falling under the formula:

and

NaOaS represents:

and

as Well as those compounds in which the second SO Na group is in S-position at the naphthalene nucleus and R represents:

and

The White effect was measured in units on the Hunter scale above the limit value of 96 at which the average human eye begins to see pure white free from yellowish hues, the so'called neutral white (hydrogen-peroxide bleached cotton attains a value of about 89 on the Hunter scale, which corresponds to about 86% of the highest theoretically attainable white of freshly prepared magnesium oxide taken as 100%). Nowadays, values above 96 which correspond to white with a slight bluish cast are preferred (viz. Hunter, New Reflectometer and Its Use for White ness Measurement in J. Opt. Soc. Am., 50, page 48 (1960).

The tests for determining the white effect on cotton after the aforesaid different storage times were carried out as follows:

A detergent composition was prepared by admixing grams of the respective brightener to be tested with 2500 grams of sodium tripolyphosphate, mixing intimately in an Osterizer sold by I. Oster Manufacturing Co., Milwaukee, Wis., and storing at about 25 C. in air of 90% humidity until constant weight has been attained. The resulting tripolyphosphate composition has a moisture content of about 3%. This tripolyphosphate composition is then mixed with sodium dichloro-isocyanurate in a Weight ratio of 85:15. 0.5 gram of the resulting detergent composition was added to 100 milliliters of cold water in a washing apparatus and a cotton cloth weighing 3.3 grams was immersed in the resulting wash liquor immediately after its preparation. The liquor was then heated to 60 C. and the cotton cloth was washed at that temperature for 15 minutes. The cloth was then washed well first in luke-warm and then in cold water and subsequently air-dried. The white elfect of the treated cloths was determined by comparison with standard samples showing degrees of whiteness corresponding to values ranging from 89-109 on the Hunter scale.

The same test was repeated with each time 0.5 gram of the aforesaid detergent composition which has been stored for thirty-two and sixty-four days, respectively.

The results were plotted in Diagrams I and II.

Storage was effected in sealed bottles at an ambient temperature of about 29 C. and an atmospheric humidity of 92%.

These tests reveal that, surprisingly, the compounds according to the invention show satisfactory pure white effects on cotton when stored in mixture with sodium dichloroisocyanurate-containing detergents even after 64 days, While known chlorine-substituted isomers and analogs of the compounds of the invention fail already after less than half that time affording only brightening effects of noticeable yellowish hues.

This renders them unsatisfactory when used in nonsoap detergents containing chlorine-yielding agents since a time span of six weeks from manufacturer to consumer must be considered a minimum.

In view of their good resistance to active chlorine, the compounds according to the invention are well suited for use in wash liquors containing such chlorine in amounts up to about 0.6 gram per liter and higher, up to 0.8 and even 1.5 grams per liter, although in the latter case, it is recommended that the Wash liquors are preferably not left standing for more than one hour, especially at temperatures above 50 C.

Preferably, the wash liquors contain not more than 0.6 gram per liter of active chlorine. Of course the compounds of Formulas I and II can also be used with equally satisfactory effect in wash liquors which contain no active chlorine.

The compounds of Formulas I and II are used in concentrations of 0.0005 to 0.1% calculated on the weight of the textile goods to be whitened, and are added to the wash liquors in amounts of from 0.001 to 0.05 gram, preferably about 0.003 to 0.01 gram per liter, depending upon the number of washing operations to be performed with one of the same liquor and the goods-to-liquor weight ratio to be applied. The latter ranges from about 1:50 to 1:3 preferably 1:30 to 1:20 in the case of manual laundering and 1:8 to 1:3 when using washing machines.

A Wash liquor as conventionally applied for the washing of cotton or nylon material contains about 2 to 5 grams per liter of wash powder, which determines the concentration of the compounds of the invention, I and II, in the latter, and from about 0.1 to 0.6 gram of active chlorine per liter, the content of active chlorine being the higher, the shorter the goods-to-liquor ratio.

Due to the good resistance of the brightening compounds I and II against active chlorine, the aforesaid wash liquor can be left standing for a prolonged period, e.g. about two hours, at temperatures of 50 C. to C.

Textile materials of cellulosic or synthetic polyamide fibers washed with the aforesaid wash liquors possess an attractive white appearance with a desirable faint violetbluish hue. Repeated laundering (10 to 20 times and more) with wash liquors having relatively high concentrations of the brightening compounds I or II further improve this pleasant appearance, without producing an undesirable faint residual hue e.g. of pink or green.

Increasing whiteness after repeated washings is also referred to as build-up and is particularly strong in the case of the compounds according to the invention, and especially compound I.

Textile materials of cellulosic fibers, especially cotton, or of synthetic polyamide fibers, especially nylon (nylon 6, nylon 66 etc.) are laundered with the wash liquors containing compound I and/or II under conventional conditions, e.g. at temperatures of 30 to 80 C. When laundering has been carried out with wash liquors having a high content of active chlorine, it is recommended that the laundered textile goods be rinsed with Water to which a de-chlorinating agent such as sodium bisulfite has been added in conventional concentration.

Active chlorine can be introduced into the abovedescribed wash liquors in any conventional manner, for instance, in the form of water-soluble salts of hypochlorous acid such as lithium, sodium or potassium hypochlorite, and in detergents also in the form of dior tri-chlorocyanuric acid or their sodium or potassium salts; N-chloro-dicarboxylic acid imides, such as N-chloro succinimide or N-chloro-malonimide, or chlorohydantoins such as 1,3-dichloro-5,S-dimethylhydantoin. In detergents, the chlorine-yielding agent is added in amounts not exceeding 20% and preferably not more than 15-16% by Weight or less, calculated on the weight of the detergent.

Detergents usable in the wash liquors are ionogenic agents such as soaps, water-soluble salts of higher fatty alcohol sulfates, higher alkyl and/ or polyalkyl-substituted aryl sulfonic acids, esters of medium to higher alkanols and sulfocarboxylic acids; higher alkanoylamino-arylcarboxylic or -sulfonic acids, or fatty acid glycerin sulfonates; also usable are non-ionogenic detergents such as higher alkylphenol-polyglycol ethers.

Furthermore, the above-described wash liquors may also contain conventional adjuvants such as alkali metal polyphosphates or -polymetaphosphates, alkali metal silicates, alkali metal borates, especially perborates, alkali metal salts of carboxy-methyl cellulose, foam stabilizers, such as alkanol amides of higher fatty acids, or complexformers such as water-soluble salts of ethylene diamino tetracetic acid.

The alkali metal salts of the compounds of Formulas I and II are obtained by coupling the diazo compound of 4-amino-3',4'-dichloro-stilbene-2-sulfonic acid or 4- amino-2,4'-dichloro-stilbene-2-sulfonic acid with a 2- aminonaphthalene optionally sulfonated in position l, and by oxidizing by conventional methods the o-aminoazo dyestutf obtained in the form of the alkali metal salt, in .particular the sodium or potassium salt, to form the naphthotriazole compound.

The 4-amino-3',4-dichloro-stilbene-Z-sulfonic acid or 4-amino-2,4-dichloro-stilbene-Z-sulfonic acid, respectively, which are used as starting materials are obtained, by known methods, for instance by the condensation of 3,4-dichlorobenzaldehyde or 2,4-dichloro-benzaldehyde with 4-nitro-toluene-2-sulfonic acid phenyl ester, saponification of the sulfonic acid phenyl ester group and reduction of the resulting 4-nitro-3',4'-dichloro-stilbene- 2-sulfonic acid or 4-nitro-2',4'-dichloro-stilbene-2-sulfonic acid.

The coupling of the diazotized 4-amino-3',4'-dichlorostilbene-Z-sulfonic acid or 4-amino-2',4-dichloro-stilbene- 2-sulfonic acid with the above-mentioned Z-aminonaphthalene is effected by conventional methods and preferably in aqueous pyridine solution; oxidation of the o-aminoazo dyestulf to form the naphthotriazole compound of Formulas I or II is performed, e.g. with oxygen or air in the presence of copper (II) salts, in particular ammonia complexes of copper sulfate, which act as catalysts.

In all of the following examples the sodium salts of the 2-(3"',4"-dichloro-stilbyl-4")-(naphtho 1',2:4,5) 1,2, 3-triazole-2"-sulfonic acid or 2-(2,4"-dichloro-stilbyl- 4" (naphtho- 1 ',2' 4,5 l ,2,3-triazole-2"-sulfonic acid are obtained. These compounds can be converted easily by conventional methods to low-soluble compounds such as alkaline earth salts, e.g. magnesium or calcium salts. However, and this goes for the whole 2-(stilbyl-4")- (naphtho-1,2:4,5)-1,2,3-triazole-2"-sulfonic acid salt group of compounds, the free sulfonic acid cannot be obtained by acidifying a solution, e.g. of the sodium salt, of such a compound. In order to produce free sulfonic acids of this group of compounds, a novel method has to be used. Thus, for instance, the sodium salt has to be converted with phosphorus oxychloride to the corresponding sulfonic acid chloride whereupon the sulfonic acid chloride has to be saponified with aqueous alkanol (via the unstable sulfonic acid alkyl ester) to form the free sulfonic acid.

The resulting free sulfonic acids can be neutralized with alkali hydroxides such as potassium hydroxide, lithium hydroxide, furthermore with ammonium hydroxide and various aliphatic and heterocyclic amines such as diethyl amine, triethyl amine, monoethanol amine, diethanol amine, triethanol amine, morpholine, pyridine, pyrrolidine, pi-peridine,, etc., to form the corresponding salts of the unsubstituted and substituted derivatives of 2- stilbyl-4" (naphtho- 1 ',2 :4,5 )-1,2,3-triazole-2"-sulfonic acid, more particularly, the corresponding salts of the compounds of Formulas I and II.

The following non-limitative exmaples illustrate the invention. Where not otherwise stated, parts and percentages are given therein by weight. The temperatures are in degrees centigrade. The relationship of parts by weight to parts by volume is that of grams (g.) to milliliters (ml.).

EXAMPLE l 5 1 Na S 0 34.4 g. of 4-amino-3',4'-dichlorostilbene 2 sulfonic acid together with NaOH are dissolved in 800 g. of water so that the solution becomes neutral. 7.0 g. of sodium nitrite are added to this solution. While stirring well, the mixture is added dropwise at a 810 to a solution of 12.8 g. of hydrochloric acid in 100 g. of Water. Then the whole is stirred for another 30 minutes at 810, the

excess nitrite is removed by means of a small amount of sulfamic acid, and the diazo suspension thus obtained is poured at a temperature of 5 to +2 into a solution of 14.2 g. of .2-aminonaphthalene in 900 g. of technical pyridine. On completion of the coupling, NaOH is added to the mixture until phenolphthalein shows an alkaline reaction. Upon addition of 180 g. 0g sodium chloride, the mixture separates into two layers. The upper, pyridine layer containing the o-aminoazo dyestuff is then mixed with a solution of 2.5 g. of crystallized copper sulfate in g. of water and 10 g. of monoethanol amine (hereinafter referred to as copper catalyst). Now a vigorous stream of air is conducted at a temperature of 9597 into the quickly stirred reaction mixture until the red o-aminoazo dyestuflf has been completely oxidized to the naphthotriazole compound. Then the copper salts are precipitated by the addition of a small excess of sodium sulfide and the copper sulfide is separated from the boiling hot solution by filtration. The aqueous pyridinic solution of triazole is now heated to boiling by direct introduction of steam and is mixed with 5 g. of sodium hydrosulfite whereupon the pyridine is evaporated by steam distillation. As soon as the major part of the crude triazole compound is removed, the steam distillation is discontinued, the mixture is slightly cooled and the crystal cake filtered 01f by suction and thoroughly washed with warm water. For further purification, the crude product is dissolved under slight reflux in about 70% aqueous technical pyridine to which some NaOH is added. Then it is cooled, and the separated product is filtered 01f, slurried with some NaOH and Water and again subjected to steam distillation to remove the excess pyridine. After complete removal of the pyridine, the mixture is slightly cooled. The precipitate is filtered off while still warm and washed on the filter with warm water. The product obtained in this Way is stirred for about 30 minutes at reflux temperature in 96% alcohol and is then cooled, filtered ofl? by suction, washed thoroughly on the filter with alcohol and then dried in vacuo at a temperature of 125.

The purified naphthotriazole compound must be examined as to whether it contains coloring impurities. 200 mg. of the product dissolved in 10 g. of dimethyl formamide should give a solution which is colorless in ultraviolet-free daylight. If the solution shows a yellowish coloring, the above-described purification steps should be repeated.

The sodium salt of the 2-(3,4'"-dichlorostilbyl-4")- (naphtho-1,2':4,5)-1,2,3-triazole-2"-sulfonic acid is obtained as a pale yellowish-green powder melting at a tem perature higher than 300.

This compound is a valuable brightening agent for cellulose fiber, polyarnide fibers, soap powders, detergents, etc. It has good fastness not only to washing and light, but also excellent fastness properties to chlorine and chlorites on substrates, in the dye liquors and in pulverulent mixtures.

The 4-amino-3,4'-dichlorostilbene-Z-sulfonic acid used as starting material is prepared in the following manner At an initial temperature of about and later g. of 3,4-dichlorobenzaldehyde are added in small portions during 8 hours to a solution of 293 g. of 4- nitro-toluene-Z-sulfonic acid phenyl ester in 150 ml. of dry toluene to which 7 g. of piperidine have been added. The mixture is kept under mild reflux. The separating Water is continuously removed by a water separator. After a reaction period of about 22 to 24 hours, the crude reaction product is slightly cooled and introduced into a mixture of 280 g. of methanol and 82.5 g. of potassium hydroxide within 1 to 2 hours at a temperature of 30-35. Then the reaction mixture is heated within 1 hour to a temperature of 62 to 64 and stirred for another 3 hours under mild reflux. The mixture is cooled to 25, stirred for 1 hour and filtered, and the residue is washed first with 50 g. of methanol and then with a solution of 5 g. of

sodium chloride in 100 g. of water. The crude product thus obtained is purified by recrystallization from boiling water and precipitated again completely by the addition of sodium chloride. The damp sodium salt of 4-nitro-3',4- dichlorostilbene 2-sulfonic acid is then reduced to the 4- amino-3',4-dichlorostilbene-Z-sulfonic acid according to the Bchamp process by means of iron and hydrochloric acid. The free sulfonic acid is obtained as a pale beige powder melting at a temperature higher than 300.

By repeating Example 1, but using in lieu of 2aminonaphthalene an equivalent amount of Z-aminonaphthalene- -sulfonic acid or 2-amino-naphthalene=6-sulfonic acid, there are obtained sodium 2-(3"',4'"-dichloro-stilbyl-4") (naphtho-1',2' :4,5 )-1,2,3-triazole-2",5'-disulfonic acid and 2,6-disulfonic acid, respectively.

EXAMPLE 2 l/ NaSO N A solution of the sodium salt of 34.4 g. of 4-amino- 3',4-clichloro stilbene-2-sulfonic acid and 7.0 g. of sodium nitrite in 800 ml. of water is indirectly diazotized at a temperature of 810 by pouring it into a solution of 12.8 g. of hydrochloric acid in 100 ml. of water. The diazo suspension is then added within 3 hours at a temperature of 5 to to a solution of 22.7 g. of 2-aminonaphthalene-l-sulfonic acid in a mixture of 900 g. of technical pyridine and 50 ml. of water. Upon completion of the diazo-reaction, stirring is continued for a short time, the 14.4 g. of sodium hydroxide in the form of a 30% aqueous solution is added until phenolplithalein clearly shows an alkaline reaction, whereupon 200 g. of sodium chloride are added. The mixture is left standing for a short time. Two layers are formed which are separated and, after addition of the copper catalyst described in Example 1, the pyridinic dyestuif solution is oxidized with air to the naphtho-triazole compound. Removal of the copper salts and purification of the crude product is effected in the same manner as described in Example 1. The sodium salt of the 2-(3"',4"-dichloro-stilbyl-4)- (naphtho-l:4,5)-l,2,3-triazole-2"-sulfonic acid is obtained as a pale yellowish-green powder having a melting point above 300. The product is identical with the compound described in Example 1.

By repeating Example 2, but using in lieu of 34.4 g. of sodium 4-amino3,4-dichloro-stilbene-Z-sulfonate an equivalent amount of sodium 4-amino-3-chloro-stilbene- 2-sultonate, there is obtained the corresponding compound of Formula 1.

EXAMPLE 3 NaSO;

A solution of 34.4 g. of 4-amino-2',4-dichlor0-stilbene- 2-sulfonic acid, 4.1 g. of sodium hydroxide and 6.9 of sodium nitrite in 800 ml. of water is indirectly diazotized by adding it dropwise at a temperature of 8-10" to a solution of 12.8 g. of hydrochloric acid in 100 ml. of water. The suspension of the diazo compound obtained in this manner is then added within 30 minutes at a temperature of -5 to +2 to a solution of 14.5 g. of 2-amino naphthalene in 900 g. of technical pyridine. On completion of coupling, about 30% aqueous sodium hydroxide solution is added until phenolphthalein shows an alkaline reaction. 180 g. of sodium chloride are added,

stirred for a short time and left standing whereupon the upper pyridine layer containing the o-aminoazo dyestutf is separated. Now, a copper catalyst consisting of 2.5 g. of crystallized copper sulfate and 10 g. of monoethanolamine in ml. of water is added, and the reaction mixture is heated to a temperature of 95-97. At the same time a vigorous stream of air is introduced with rapid stirring until the red color has disappeared, and the oarninoazo dyestufi has been converted to the triazole compound. Subsequently, the copper salts are converted to copper sulfide by the addition of a small excess of sodium sulfide and filtered off. After the addition of 5 g. of sodium hydrosulfite, the pyridine is removed with the aid of steam until the major portion of the crude prod not has been precipitated. The cooled solution is filtered off, the filtrate is washed well with warm water, the crude product is recrystallized as described in Example 1 from 70% aqueous technical pyridine, the adhering pyridine is removed and other colored by-products are extracted with alcohol. The purified sodium salt of 2-(2",4"-dichloro-stilbyl-4)-(naphtho-1',2:4,5 )-1,2,3 triazole 2"- sulfonic acid is obtained as a pale yellowish powder having a melting point above 300. The compound is a valuable brightening agent for cellulose fibres, soap powders, detergents and the like and, when dissolved in a wash liquor or used on a substrate, has excellent fastness to active chlorine and chlorites.

Preparation of 4-amino-2',4'-dichloro-stilbene-Z- sulfonic acid At an initial temperature of about which is then raised to g. of 2,4-dichlorobenzaldehyde are added in small portions Within 8 hours under mild reflux to a solution of 293 g. of p-nitrotoluene sulfonic acid phenyl ester in 150 g. of dry toluene to which 7 g. of piperidine are added. The separating water is continuously removed by means of a separator. After a total reaction period of about 22m 24 hours, the crude reaction product is cooled and introduced within 1 to 2 hours at a temperature of 30 to 35 into a mixture of 280 g. of methanol and 82.5 g. of otassium hydroxide solution. Then the reaction mixture is heated for 1 hour to a temperature of 62 to 64 and stirred for another 3 hours under mild reflux. It is cooled to 25, stirred for 1 hour, and filtered. The residue is washed first with water, then with a solution of 5 g. of sodium chloride in 100 ml. of water. The crude product thus obtained is cleaned by recrystallization from boiling water and again completely precipitated by the addition of sodium chloride. The wet sodium salt of 4-nitro-2',4'-dichloro-stilbene-2-sulfonic acid is then reduced according to the Bchamp method by means of iron and hydrochloric acid to form 4-amino- 2',4'-dichloro-stilbene 2 sulfonic acid. The free sulfonic acid is obtained as a pale beige powder having a melting point above 300.

By repeating Example 3, but using in lieu of 14.5 g. of Z-amino-naphthalene an equivalent amount of 2- amino-naphthalene-5-sulfonic acid, there is obtained the corresponding 2,4"'-dichloro stilbyl substituted naphthotriazole-2",5'-disulfonic acid.

EXAMPLE 4 C1 C.@CH:CH@ N N A solution of the sodium salt of 34.4 g. of 4-amino- 2',4-dichloro-stilbene-Z-sulfonic acid and 6.9 g. of sodium nitrite in 500 ml. of water is indirectly diazotized at a temperature of 8 to 10 by pouring it into a solution of 12.8 g. of hydrochloric acid in 100 ml. of water. Then, at a temperature of 5 to 10, this suspension of the diazo compound is added within 3 to 4 hours to a solution of 22.7 g. of 2 aminonaphthalene-l-sulfonic acid in a mixture of 600 g. of technical pyridine and 100 ml. of water. On completion of the diazo-reaction, stirring is continued for a short time, then 14.5 g. of sodium hydroxide in the form of a 30% aqueous solution is added until phenolphthalein shows a clearly alkaline reaction, whereupon 140 g. of sodium chloride are added. The mixture is left standing for a short time, two layers form which are separated anid, after addition of the copper catalyst described in Example 1, the pyridinic dyestuff solution is oxidized with air to form the triazole compound. After working up and purifying as described in Example 1, the sodium salt of 2-(2"',4"'- dichloro-stilbyl-4")-(naphtho l',2':4,5)-1,2,3 triazole- 2"-sulfonic acid is obtained as a pale yellowish powder having a melting point above 300". The product is identical with the compound described in Example 3.

EXAMPLE 5 0.09 g. of active chlorine in the form of an aqueous sodium hypochlorite solution is added to a wash liquor at a temperature of 60 containing 1.5 g. of a detergent which consists of 8 parts of lauryl sulfate, 11 parts of dodecyl benzene sulfonate, 11 parts of sodium tripolyphosphate, 17 parts of sodium pyrophosphate, 4.5 parts of sodium silicate, 1.8 parts of carboxymethyl cellulose, 37 parts of sodium sulfate, 8 parts of sodium perborate and 1.7 parts of water as well as 0.0017 g. of a brightening agent of the formula:

in 300 ml. of water. The wash liquor is left standing for 1 hour at 60 and is then used for washing g. of untreated cotton fabric during minutes at the same temperature. Then the fabric is rinsed first in lukewarm and then in cold water and is dried. The cotton fabric treated in this manner appears highly brightened in daylight When the fluorescence of this fabric is measured on a Fluorometer, Type 240 (manufactured by E. Schildknecht, Zurich, Switzerland), a fluorescence value of 81 is obtained.

However, when the brightening agent used in the above example is replaced by 0.0021 g. of a compound of the formula:

and this example is otherwise repeated, an untreated cotton fabric washed with the resulting liquor has practically the same appearance in day light as cotton fabric which has not been brightened. Measurement on the same fluorometer gives a fluorescence value of not more than 5.

When the same washing test is performed without the addition of active chlorine, the. same visual brightening effect is obtained with the first-mentioned compound its fluorescence value being 108 while fabric treated with the second-mentioned compound even shows a fluorescence value of 113. This shows that when the wash liquor is left standing for a long time, only the first-mentioned compound has sufiicient stability to active chlorine, whereas, under the same conditions, the second compound is practically destroyed.

Furthermore, when polyamide fabrics present irfi household laundry, such as nylon 6, nylon 66, and the like are washed with wash liquors containing the first-men- 12 tioned compound, they are brightened together with the cotton fabric.

EXAMPLE 6 0.09 g. of active chlorine in the form of an aqueous sodium hypochlorite solution is added to a wash liquor at a temperature of 60 containing 1.5 g. of a detergent which consists of 8 parts of lauryl sulfate, 11 parts of dodecyl benzene sulfonate, 11 parts of sodium tripolyphosphate, 17 parts of sodium pyrophosphate, 4.5 parts of sodium silicate, 1.8 parts of carboxymethyl cellulose, 37 parts of sodium sulfate, 8 parts of sodium perborate and 1.7 parts of water as well as 0.0020 g. of a brightening agent of the formula:

NaSO N in 300 ml. of water. The wash liquor is left standing for 1 hour at 60 and is then used for washing during 15 minutes at the same temperature 10 g. of untreated cotton fabric. Then the fabric is rinsed first with lukewarm and then with cold water and is dried. In daylight, the fabric treated in this manner appears as highly brightened. Measurement of the fluorescence of this fabric on the Fluorometer mentioned in the preceding example, yields a fluorescence value of 97.

When the brightening agent mentioned in the above example is replaced by 0.0021 g. of a compound of the formula:

NaSO

while repeating the example in all other details, the resulting washed cotton fabric appears as untreated in daylight, i.e. it is practically not brightened. When measured on the same fluorometer, its fluorescence value is not more than 5. When the same washing test is performed without the addition of active chlorine in the form of an aqueous sodium hypochlorite solution, the same visual brightening effect is obtained with the first-mentioned compound, its fluorescence value being 106, while the second compound gives a fluorescence value of 113.

Furthermore, if polyamide fabrics which occur in household laundry, such as nylon 6, nylon 66 and the like, are washed with wash liquors containing the firstmentioned compound, they are brightened simultaneously with the cotton fabric.

EXAMPLE 7 Cl CH=CH The fabric is gently stirred for 15 minutes, then it is rinsed first with lukewarm and then with cold water and finally dried. The cotton fabric washed in this manner has a beautiful brightening effect in day light. This fabric measured on the Fluorometer mentioned in the preceding examples yields a fluorescence value of 101.

When this cotton fabric is treated, analogous to household practice, under the same conditions with further wash liquors of the same composition; the brightening effect increases gradually as shown in the following table.

Without addition of chlorine- Fluorescence values Number of washings:

However, when the above-described washing process is carried out in such a way that at a temperature of 60 and 5 minutes before introducing the cotton fabric into the wash liquor, 0.18 g. of active chlorine in the form of a sodium hypochlorite solution is addedwhile the conditions are otherwise the same as described in the above example and when the fabric is treated after washing in a dechlorination bath containing 0.3 g. of sodium bisulfite in 300 ml. of water and lasting for 5 minutes (room temperature) which is applied between the lukewarm and the cold rinsing step, the cotton fabric treated in this manner shows a fluorescence value of 101.

When treatment of the cotton fabric is continued under the same conditions with further chlorine-containing wash liquors of the same composition, the brightening effect increases gradually as shown in the following table:

With the addition of 0.18 g. of active chlorine in the form of sodium hypochlorite- Number of washings: Fluorescence values 1 101 The same methods and conditions are applied as in the above examples but only 0.0009 g. of the brightening agent are used instead of 0.0011 g., whereupon the following fluorescence values are obtained:

With the addition of 0.18 g. of active chlorine in the form of sodium hypochlorite- Number of washings: Fluorescence values In this way, a brilliant white effect is obtained in spite of the active chlorine present in the wash liquors.

The amount of brightening agent mentioned in the above example may be largely varied. Wash liquors can be used which contain from 0.0003 g. to 0.003 g. of brightening agent. The number of baths required to achieve the maximum effect changes accordingly. Further, the composition of the above detergents can be changed. Also the amount of active chlorine added to the liquors can be varied. Besides sodium hypochlorite solution, corresponding amounts of hypochlorite compounds can be used which have been stabilized or converted to solid form, respectively. Moreover, the hypo chlorite can be replaced by other compounds supplying active chlorine, such as dichloroor trichloro-cyanurates, their alkali salts or N-chloro-succinimide, N-chloromalonimide or hydantoins, such as 1,3-dichloro-5,5-dimethyl hydantoirl.

The measured fluorescence values vary with the time period before the introduction of the cotton fabric and with the temperature of the wash liquor.

Polyamide fabrics which may be simultaneously present in the wash, such as nylon 6 or nylon 66, are also brightened by the above-described washing processes.

14 EXAMPLE 8 10 g. of an untreated cotton fabric are introduced into 300 ml. of a wash liquor of a temperature of 60 containing 1.5 g. of a detergent which consists of 15.2 parts of dodecyl benzene sulfonate, 3.8 parts of lauryl sulfate, 25.6 parts of sodium tripolyphosphate, 7.6 parts of tetrasodium pyrophosphate, 4.8 parts of sodium silicate, 1.9 parts of magnesium silicate, 5.0 parts of sodium carbonate, 1.4 parts of carboxymethyl cellulose, 0.3 parts of sodium ethylene diamine tetraacetate and 34.4 part of sodium sulfate, as well as 0.0011 g. of the compound of the formula:

Number of washings: Fluorescence values When the above-described washing process is carried out in such a way that 0.18 g. of active chlorine in the form of a sodium hypochlorite solution is added at a temperature of 60 and 5 minutes before introducing the cotton fabric into the wash liquor, while the other conditions are the same as given in the above example, and when a dechlorinaiton bath containing 0.3 g. of sodium bisulfate in 300 ml. of water and lasting for 5 minutes (room temperature) is applied to the washed fabric between the lukewarm and the cold rinsing step, the cotton fabric thus treated shows a fluorescence value of 105.

When the cotton fabric is treated under the same conditions with further chlorine-containing w ash liquors of the same composition, the brightening effect increases gradually as shown in the following table:

With the addition of 0.18 g. of active chlorine in the form of sodium hypochlorite-- Number of washings: Fluorescence values Number of washings: Fluorescence values In this way, a beautiful white effect is obtained in spite of the amount of 0.6 g. of active chlorine present in every liter of the wash liquors.

The amount of the brightening agent mentioned in the above example can be largely varied. Wash liquors can be used which contain from 0.0003 to 0.003 g. of brightening agent. The number of baths required to achieve the maximum efiect changes accordingly. Furthermore, the composition of the above-mentioned detergent can be changed. Equally, the amount of active chlorine added to the liquors can be varied. Moreover, the fluorescence values measured will be influenced by changes in the time period between the addition of the active chlorine and the introduction of the cotton fabric as well as by changes in the temperature of the wash liquor.

EXAMPLE 9 10 g. of an untreated cotton fabric are introduced into 300 ml. of a wash liquor at a temperature of 60 containing 1.5 g. of the detergent described in Example 4 and 0.0011 g. of the compound of the formula:

The cotton fabric is gently stirred for 15 minutes. Then it is rinsed first with lukewarm and then with cold water and finally dried. When this fabric is measured on the Fluorometer used in the preceding examples, a fluorescence value of 106 is obtained. When this cotton fabric is treated under the same conditions with further wash liquors of the same composition, the brightening effect of the fabric increases as shown in the following table:

Without the addition of chlorine- Number of washings: Fluorescence values 1 106 5 118 122 When the above-described washing process is carried out in such a manner that 0.18 g. of active chlorine in the form of sodium hypochlorite solution is added at a temperature of 60 and 5 minutes before introducing the cotton fabric into the wash liquor, while the other conditions are the same as in the above example, and when a dechlorination bath containing 0.3 g. of sodium bisulfate in 300 ml. of water and lasting for 5 minutes (room temperature) is applied to the washed fabric between the lukewarm and the cold rinsing step, the cotton fabric treated in this way shows a fluorescence value of 95. When this cotton fabric is treated with further wash liquors of the same composition, the brightening effect increases as shown in the following table:

With the addition of 0.18 g. of active chlorine in the form of sodium hypochlorite- NaSOa Number of washings: Fluorescence values 1 95 5 t 107 10 110 Number of washings: Fluorescence values 16 When the brightening agent mentioned in the above example is replaced by 0.0011 g. of the compound of the formula: I

NaSO;

the other conditions being the same as before, the following values are obtained for several washing treatments:

With the addition of 0.18 g. of active chlorine in the form of sodium hypochlorite- Number of washings: Fluorescence values Number of washings: Fluorescence values When the brightening agent is replaced by 0.0011 g. of the compound of the formula:

NaSOa all other conditions being the same as above, the following values are obtained:

With the addition of 0.18 g. of active chlorine in the form of sodium hypochlorite- Number of washings: Fluorescence values When the same process and conditions are applied as in the above example but only 0.0009 g. of the same brightening agent is used instead of 0.0011 g., the following fluorescence values are obtained:

With the addition of 0.18 g. of active chlorine in the form of sodium hypochlorite Number of washings: Fluorescence values If the brightening agent is replaced by 0.0011 g. of the compound of the formula:

NaSO

all other conditions being the same as above, the following values are obtained:

17 With the addition of 0.18 g. of active chlorine in the form of sodium hypochlorite- Number of washings: Fluorescence values Number of washings: Fluorescence values 10 g. of an untreated nylon fabric are introduced into 200 ml. of a wash liquor at a temperature of 40 containing 1.0 g. of a detergent which consists of 15.2 parts of dodecyl benzene sulfonate, 3.8 parts of lauryl sulfate, 25.6 parts of sodium tripolyphosphate, 7.6 parts of tetrasodium phosphate, 4.8 parts of sodium silicate, 1.9 parts of magnesium silicate, 5.0 parts of sodium carbonate, 1.4 parts of carboxymethyl cellulose, 0.3 part of sodium ethylene diamine tetraacetate and 34.4 parts of sodium sulfate as well as 0.0006 g. of the compound of the fol lowing formula:

NaSO

The nylon fabric is gently stirred for minutes, then it is rinsed first with lukewarm and then with cold water and finally dried. The nylon fabric washed in this manner has a beautiful white effect in daylight. When this fabric is measured on the Fluorometer used in the preceding examples, a fluorescence value of 57 is obtained.

When this nylon fabric is treated, analogous to household practice, under the same conditions with further wash liquors of the same composition, the brightening effect is increased as shown in the following table:

Number of washings: Fluorescence values When the brightening agent mentioned in the above example is replaced by 0.0007 g. of the compound of the formula:

NaSOa the other conditions being the same as before, the following fluoroscence values are obtained for several washing treatments:

Number of washings: Fluorescence values EXAMPLE 11 A heavy duty detergent mixture consisting of Parts by wt.

Lauryl sulfate 8.2 Dodecyl-benzene sulfonate 11.0 Sodium tripolyphosphate, (Na P O 11.0 Tetrasodium pyrophosphate 17.6 Anhydrous sodium silicate 4.6 Carboxymethyl cellulose 1.4

Sodium sulfate 38.2 Sodium perborate (NaBO +4H O) 8.0 Sodium 2 (2',4"-dichloro-stilbyl-4")-(naphthol',2' 4,5 -1,2,3-triazole-2"-sulfonate 0.08

is produced in the following manner:

The optical brightener is intimately mixed with normal aqueous sodium hydroxide solution (10 ml. per g. of brightener) and when the brightener is thoroughly dispersed, about 200 to 300 ml. of water (per gram of brightener) are added.

The other ingredients of the detergent mixture are mixed with each other separately and intimately using a sufficient amount of water to obtain a creamy paste, the latter is dried at 60 and granulated.

The detergent granules are then added to the slurry of brightener and the mixture is repeatedly and thoroughly stirred until a smooth, creamy mix is obtained. The resulting slurry is then spread into a uniform layer on a fiat surface and dried in an oven at for 16 hours. The resulting cake is allowed to cool to room temperature, left standing for at least 30 minutes and then crushed in a desiccator. The dried chunks of detergent mixture are then forced through a 20 mesh screen and, if desired, the resulting powder is transferred to a 60 mesh screen to remove the fine portion.

A similar mixture is obtained by replacing the brightener in the above example by 0.06 part of sodium 2-(3"', 4"'-dichloro-stilbyl 4") (naphtho-1',2':4,5)-1,2,3-triazole-2-sulfonate.

EXAMPLE 12 In a similar manner as described in Example 11 there is produced a synthetic, non-soap, heavy-duty detergent of the following composition (in percent by weight):

Dodecyl benzene sulfonate 15.2 Lauryl sulfate 3.8 Sodium tripolyphosphate 25.6 Tetrasodium pyrophosphate 7.6 Anhydrous sodium silicate 4.8 Magnesium silicate 1.9 Sodium carbonate 5.0 Carboxymethyl cellulose 1.4 Sodium ethylenediamine tetraacetate 0.4 Sodium 2 (3"',4-dichloro-stilbyl 4")-naphtho- 1,2':4,5)-l,2,3 triazole-2"-sulfonate 0.057

EXAMPLE 13 A heavy-duty non-soap detergent mixture consisting of 8 parts of lauryl sulfate, 11 parts of dodecylbenzene sulfonate, 11 parts of sodium tripolyphosphate, 17 parts of tetrasodium pyrophosphate, 4.4 parts of sodium silicate, 1.8 parts of carboxymethyl cellulose, 8 parts of sodium perborate, 37 parts of sodium sulfate and 1.7 parts of water is worked up into a paste with a solution of 0.06 part of the sodium salt of 2-(3"',4'"-dichloro-stilbyl-4")- (naphtho l,2':4,5) 1,2,3-triazole-2"-sulfonate in parts of water. This paste is dried at 60 and then milled. In daylight, the washing powder obtained has a con- 19 siderably whiter appearance than the same washing composition produced without the addition of the optical brightening agent.

Beautiful white Washing powders are also obtained if, instead of the brightening agent mentioned above, 0.08 part of the sodium salt of 2-(2",4"-dichloro-stilbyl-4")- (naphtho-1,2:4,5) 1,2,3 triazole-2"-sulfonate is incorporated into the above washing agent preparation.

EXAMPLE 14 A heat-liquifiable soap for use in washing machines is produced as follows:

To a hot mixture of- 40 parts by weight of coconut oil fatty acid sodium soap 31 parts by weight of sodium tripolyphosphate 9 parts by Weight of tetrasodium pyrophosphate 6 parts by weight of sodium silicate 3 parts by Weight of magnesium silicate 0.5 part by weight of sodium ethylenediamine tetraacetate 5 parts by weight of sodium carbonate 5.5 parts by weight of sodium sulfate and 70 parts of water,

tion is prepared, all amounts being expressed as parts by weight:

Sodium alkyl benzene sulfonate (the alkyl group being derived from polypropylene and averaging 12 carbon atoms per molecule) 18.0 Sodium tripolyphosphate 48.0 Water soluble sodium silicate solids 6.0 Sodium sulfate 16.8 Monoethanolamide of coconut oil fatty acids having from to 14 carbon atoms 2.7 Water, carboxymethylcellulose, tarnish inhibitor and perfume 8.5 Sodium salt of 2 (3"',4"' dichloro stilbyl 4")- (naphtho 1',2,:4,5) 1,2,3 triazole 2" sulfonate 0.08

The above composition is prepared in a similar manner as described in Example 11.

EXAMPLE 16 A laundering composition for use in washing white fabrics is prepared with:

Parts by wt. Condensation product of tall oil and ethylene oxide containing 1.6 parts of ethylene oxide per part of tall oil 16.0 Sodium tripolyphosphate 21.0 Sodium pyrophosphate 21.0 Water-soluble sodium solids 10.0 Carboxymethyl cellulose 1.0 Sodium salt of 2 (3"',4" dichloro stilbyl 4")- '(naphtho 1',2:4,5) 1,2,3 triazole 2" sulfonate 0.03

Water 11 A similar laundering composition is obtained if, instead of the brightener mentioned above, the same amount of the sodium salt of 2 (2',4" dichloro stilbyl 4")- (naphtho 1,2':4,5) 1,2,3 triazole 2 sulfonate is incorporated into the above composition.

20 EXAMPLE 17 The following liquid laundering composition is prepared, all amounts being expressed as parts by weight:

Parts Sodium alkyl benzene sulfonate (the alkyl group being derived from polypropylene and averaging 12 A similar liquid laundering composition is obtained if, instead of the brightener mentioned above, the same amount of the sodium salt of 2-(2"',4"-dichloro-stilbyl- 4") (naphtho 1',2':4,5) 1,2,3 triazole 2" sulfonate is incorporated into the above composition.

The laundering compositions described in Examples 11- 17 inclusive are very well suited for use in wash liquors for the laundering of cotton or nylon and afford a very good whitening eflect on these textile materials, also in cases where the wash liquors contain active chlorine in amounts to up to 0.8 g. per liter.

EXAMPLE 18 52 g. of the sodium salt of 2-(3",4'"-dichloro-stilbyl- 4")-(naphtho-1',2':4 ,5)-1,2,3-triazole 2." sulfonic acid are introduced into 160 ml. of dry chlorobenzene, and While stirring any residual water is removed by azeotropic distillation. Then 30 ml. of phosphorus oxychloride are added within 15 to 30 minutes at a temperature of to and the mixture is stirred for 4 to 6 hours under reflux. After cooling, it is poured at a temperature of 0 to 5 into a total of 1500 ml. of an ice-water mixture and stirred for 30 minutes; then it is filtered and thoroughly Washed with cold distilled water. The damp residue is dried in vacuo at an initial temperature of 30 to 40 *Which is then raised to to whereupon the crude product is recrystallized from boiling chlorobenzene. 2(3"',4"'-dichloro stilbyl 4")naphtho -1,2':4,5) 1,2, 3-triazole-2"-sulfonic acid chloride is obtained as a yellowish powder having a melting point of 267 to 269 (uncorrected).

10 g. of this 2-(3"',4'-dichloro stilbyl 4") (naphtho-1,2':4,5)-1,2,3-triazole-'2"-sulfonic acid chloride are added at a temperature of 70 to 75 to a mixture of 300 ml. of Cellosolve (96%) in 40 ml. of water and stirred for 30 to 40 hours under reflux. While stirring the alcohol is distilled off under normal pressure. In the course of the distillation, the free sulfonic acid begins to separate in the form of a thick crystal cake. At this time, about 60 to 90 ml. of water are gradually added so that the reaction mixture can be further stirred. When a distillation temperature of 97 to 98 has been reached, the contents of the reaction vessel is cooled, filtered, washed with a total of 200 ml. of distilled water and dried in vacuo at a temperature of 120 to 125. 2-(3"',4'"-dichloro-stilbyl-4")- (naphtho-l',2:4,5)-1,2,3-triazole-2-sulfonic acid is obtained as a pale yellowish powder. By reacting an aqueous alcohol solution of this acid with an equimolecular solution of potassium hydroxide, lithium hydroxide or ammonium hydroxide, the potassium or lithium or ammonium salts of the 2-(3",4"'-dichloro stilbyl-4")-(naphtho-1',2:4,5)-1,2,3-triazole-2"-sulfonic acid are obtained. All of these compounds are yellowish powders. They are also valuable brightening agents and differ from the so- 21 dium salts only in their solubility and aflinity to cotton and nylon.

When in the above example the sodium salt of 2-(3", 4-dichloro-stilbyl-4")-(naphtho l,2':4,5) 1,2,3 tri aZo1e-2-sulfonic acid is replaced by equal parts of the sodium salt of 2-(2,4-dichloro-stil'oyl-4)-(naphthol',2:4.5)-1,2,3-triaZole-2"-sulfonic acid While methods and conditions remain otherwise unchanged, 2-(2",4- dichloro-stilbyl4")-(naphtho1,2:4.5) 1,2,3 triazole- 2-sulfonic acid chloride is obtained as a greenish-yellow powder having a melting point of 273 to 277 (uncorrected) which further yields the free sulfonic acid and, by reaction with alkali, the corresponding alkali salts of 2-(2',4-dichlorostilbyl-4)-(naphtho 1,2:4,5) 1,2, 3-triazole-2"-sulfonic acid. The free sulfonic acid as well as its alkali salts are brightening agents which have similar properties as the above-mentioned compounds.

EXAMPLE 19 in order to obtain a storable non-soap detergenbcontaining brightener and chlorine-yielding agent, the following components were dry blended in the proportions given below, limonene, perfume, and white mineral oil being sprayed in the other substances of the composition While tumbling them:

Parts Spray dried pentasodium tripolyphosphate 60 Sodium dodecylbenzenesulfonate (containing approximately 3% moisture) 7.3 Sodium sulfate 90 Sodium carbonate d-Limonene 0.35

Perfume 0 .35 Potassium dichlorocyanurate 30.5 White mineral oil 0.5

Sodium 2-(3"'-chloro-stilbyl-4) (naphtho 1,2:

4,5)-1,2,3-triaZole-2-sulfonate 0.35

The resulting detergent powder can be shipped and stored for at least two months in bottles or paper bags and does not require any special precautions for protection against atmospheric moisture such as hermetically sealed, air-tight polyethylene pouches or aluminum-foil covered cardboxes.

Detergent compositions of similar properties which are equally storable under similar conditions are obtained by replacing in the detergent composition of Example 19 the optical brightener by one of the brighteners produced according to Examples 1 and 3 or a mixture of such brighteners.

Similarly, potassium dichlorocyanurate can be replaced by an equal amount of the corresponding sodium salt, or by trichlorocyanuric acid, dichloroisocyanuric acid, dichloro-dimethyl-hydantoin, chlorinated trisodium phosphate or N,N-dichloro-benzoylene urea.

We claim:

1. An optical brightener having the formula:

where M is alkali metal, alkaline earth metal, hydrogen or ammonium.

2. An optical brightener having the formula:

where M is alkali metal, alkaline earth metal, hydrogen or ammonium.

3. An optical brightener having the formula:

Where M is alkali metal, alkaline earth metal, hydrogen or ammonium.

4. An optical brightener having the formu a:

All MOaS SOaM where M is alkali metal, alkaline earth metal, hydrogen or ammonium.

5. An optical brightener having the formula:

U1 MOsS References Cited UNITED STATES PATENTS 2,784,183 3/1957 Keller et a1 260-240 3,101,333 8/1963 Adams et a1 260240 3,119,820 1/1964 Adams et a1. 260-240 FOREIGN PATENTS 717,889 11/1954 Great Britain. 1,316,171 12/1962 France.

JOHN D. RANDOLPH, Primary Examiner US. Cl. X.R.

Images