DE2123270A1 - Optical brightener dispersions - made by adding complexes with low molecular cpds to aq solns - Google Patents

Abstract

Aq. dispersions of optical brighteners (A) of low solubility, are made by adding their association (electron doner-acceptor) complexes with cpds. (B) of low m. wt. to solns. of polymeric substances (C) opt. contg. surfactants. (A) pref. has solubility below 5 g./l in water, (B) are pref. carboxylic acid amides or imides, urea, sulphoxide, unsat. carboxylic acid, or dimethyl formamide. (C) is pref. a vinyl polymer, graft polymer of vinyl cpds. on polyethers and/or polyacetals, or homo- and co-polymers of maleic acid and its derivs. Stable dispersions are readily obtained without tedious milling procedures and of any required viscosity. They are suitable for brightening textiles and paper and for incorporation in detergent powders.

Description

Stable Aqueous Dispersions of Optical Brighteners The present The invention relates to stable aqueous dispersions which are poorly soluble in water and which are optical Whitening agents, their manufacture and use.

It is generally known that such dispersions can be produced by that in a first stage the optical brightener is relatively more expensive By means of suitable grinders, such as sand or bead mills, up to an optional one Grain size from a, 3 to 0.5 / u crushed and the resulting system in a second Stage by adding dispersants that coat the brightener particles, stabilized. (See Ullmann, Enzykopädie der techn. Chemie, Edition B, Volume 1, p. 718).

The pearl or sand mills to be used for comminuting the active ingredient however, have a number of disadvantages upstream operation must be prepared because active ingredient, water, dispersant and optionally a surfactant, must be mixed. Furthermore, a certain Viscosity must not be exceeded. This is a restriction on the concentration of active ingredient and thus the space-time yield.

After being discharged from the mill, the material to be ground must be removed from the grinding media be separated. If the surfactant or dispersant is not added from the start was closes now a second mixing process to which the further process steps, e.g. spray drying, etc. follow.

It has now been found that stable aqueous solutions can be obtained in a simple manner Dispersions of optical brighteners that are sparingly soluble in water are obtained - if one Association complexes from these brighteners and water-soluble, low molecular weight Complexing agents in aqueous solutions optionally containing surface-active agents of polymeric compounds enters.

Association complexes of optical brighteners have not yet been described been. It was therefore not obvious to use these for the production of aqueous dispersions to use from brighteners.

The term "complexes" used here includes electron donor acceptor complexes, in the literature also often referred to as charge transfer complexes, to be understood such as Briegleb in "Electron Donor Acceptor Complexes" (Springer Verlag Berlin 1961, pp. 1-7).

The so-called charge-transfer band is characteristic of such complexes (CT band in the absorption spectrum.

To measure the CT band, one proceeds in such a way that the increase in Absorbance in the visible or ultraviolet spectral range versus the extinction the donor (D) and acceptor (A) are measured, i.e. the extinction modulus is determined; the is suitable for comparing different complexes of the same kind. For investigation of the module, the following measurement parameters are defined: t Do J = -10) molar = donor (Brightener) concentration Z 2.7 = molar = acceptor concentration.

Dioxane is used as the solvent; 1.3-Dinitrobenzene serves as the acceptor.

The measured data are at a layer thickness d [= 1 cm] and a measuring temperature of 200 ° C., the extinction differences #E in the absorption flanks at 450 and 550 µ drained: # E450-500 total = E 450 total = E500 total Since the complex AD is longer-wave as components A and D are absorbed, the change in absorbance is from formation of the complex AD dependent and then defined as follows: AD total A D ## E450-500 = # E450-500 - # E450-500 - # E450-500 AD AD ## E450-500 = ## m450-500 To simplify the notation the indices are omitted in the following and instead of ## m450-500 AD simply adm needed. vonAm450500 By specifying the dd m value, the complex sufficiently defined: a high value indicates a high affinity.

Such optical brightening agents are used according to the invention, whose solubility in water is preferably below 5 g per liter and whose Association complex with 1,3-dinitrobenzene under the standard conditions given above have an m-value between 5.10 3 and 600.10.

In particular, these are: 1,3-Diaryl-pyrazolines, as z. @.

in Austrian Patent 260,924, French Patent 1,453,061, German Patent 1,080,963, British Patent 883,826 and Swiss Patent 415,535, in particular ## m = 385.10-3 ## m = 600.10-3 ## m = 388.10-3 ## m = 325.10-3 ## m = 335.10-3 ## m = 316.10-3 3-aryl- or 5-IIeteryl-carbostyrils, as described, for example, in British patents 1.087.375 and 1.103-531, in particular ## m = 517.10-3 styrylbenzoxazoles, as described, for example, in French patent 1,397,629, in particular da ta = 13 @ 10 -5 3-aryl or 3-heteryl coumarins, e.g.

## m = 7 # 10-3 Furthermore, optical brighteners which are sparingly soluble in water and which contain a pyrene core, as described, for example, in Belgian patent specification 625,678 and British patent specification 1,141,454, in particular ## m = 237 # 10-3 Tetrahydrothionaphtene as described in German patent application P 19 55 809.1, in particular ## m = 85 # 10-3 bis-benzoxazolylthiophenes according to German patents 1.166.197 and 1.226.58), e.g.

Am m = 5-10-3 bis-benzimidazolylethylenes according to German patents 883.286 and 841.752, for example: ## m = 74 # 10-3 bis-benzoxazolylstilbenes according to American patents 3,260,715 and 3,322,680, e.g. ## m = 57 # 10-3 and bis-triazinylstilbene according to Swiss patent 472.416, Low molecular weight complexing agents are water-soluble, colorless, low-odor and physiologically harmless compounds, preferably those with amide groups, such as open-chain and cyclic carboxamides and imides and ureas, but also sulfoxides and unsaturated, preferably polybasic carboxylic acids.

Suitable amides are, for example: methylformamide, dimethylformamide, diethylformamide, Dimethylacetamide, pyrrolidone, piperidone, N, N-dimethylthioacetamideß acrylamide.

Suitable imides are, for example: maleimide, N-methylmaleinimide, N-ethylmaloinimide, N-propyl maleimide, N-butyl maleimide, N- (ß-hydroxyethyl) maleimide, succinimide, Phthalimide, N-methylphthalimide, N-butylphthalimide, N- (ß-hydroxyethyl) -phthalimide.

Suitable ureas are, for example: urea, methyl urea, N, N-dimethyl urea, N, N'-dimethyl urea, ethylene urea.

Suitable sulfoxides are, for example: DimethylRR Oxi (i and diethyl sulfoxide.

Suitable unsaturated carboxylic acids are, for example: maleic acid, phthalic acid, Tetrachlorophthalic acid, 4,5-dimethylphthalic acid @@ acrylic acid.

The water-soluble polymers to be used according to the invention are used preferably the following types in question: 1) vinyl polymers 2) graft polymers of Vinyl compounds on polyethers and / or polyacetals 3) Homo- and copolymers of maleic acid and its derivatives.

Suitable vinyl polymers are homo- and copolymers of vinylpyrrolidone, Vinyl piperidone, vinyl alcohol, vinyl acetamide, vinyl formamide, N-methylacrylamide, acrylamide, Methacryloyl taurine, - Hydroxyethyl or hydroxypropyl (meth) acrylate. Furthermore, water-soluble, i.e. polyvinyl esters containing carboxyl groups are suitable.

Of these, polyvinylpyrrolidone and polyhydroxyethyl acrylate are particularly preferred to call.

Suitable graft polymers are those of vinyl acetate and / or Vinyl pyrrolidone on polyether made from ethylene oxide and / or propylene oxide or polyacetals from di- and / or triethylene glycol and formaldehyde, provided they are water-soluble.

The production of such graft polymers is known and is for example in the German Auslegeschriften 1,111,394, 1,077,430 and 1,161,423 described.

Suitable polymers derived from maleic acid Homo- and copolymers of maleic acid itself or

their anhydride, their esters and amides, but especially their half-esters and / or ilalbamides and cyclic amides (imides), provided they have a sufficient number contained by water-solubilizing groups.

The half esters are prepared in a known manner by the corresponding maleic anhydride polymers in the presence or absence of a solvent or dispersant reacts with alcohols. Preferred alcohols are those Monohydroxylverbindungen used which either contain a maximum of 6 carbon atoms such as Methanol, ethanol or cyclohexanol or water-soluble addition products of at least 2 moles of ethylene oxide to a hydroxyl-containing starter substance such as p-phenylphenol or oleyl alcohol, isononylphenol, phenol, butanol, etc.

represent. For example, addition products of approx. 13 mol Ethylene oxide of p-phenylphenol or of about 10 mol of ethylene oxide of isononylphenol. The representation the polymeric half-ester can also be carried out in a simplified manner by first represents the corresponding maleic acid half esters and these then the homo- or subjected to copolymerization, for example with styrene, vinyl acetate or vinyl ethers. These alcohols can also be used in a stoichiometric excess or, preferably, in excess are used, and they can optionally act as a solvent.

The half-amides are preferred by reaction of maleic anhydride polymerization with primary or secondary amines, amine mixtures such as ammonia, methylamine, Diethanolamine, cyclohexylamine or benzylamine prepared in a known manner, preferably becomes cyclohexylamine and / or diethanolamine.

Of course, you can also use both alcohol as well as amine mixed half-ester-half-amide polymers are produced and used will.

Suitable homo- and copolymers of maleimide are, for example such as those in German Offenlegungsschrift 1.595.704 and the Belgian Patent 745,157 are described.

Copolymers of maleic anhydride are preferred in this group and styrene use with addition products of ethylene oxide to phenyl-phenol or nonylphenol and cyclohexylamine have been reacted and directly or in the form their ammonium salts are water-soluble.

The molecular weights of the polymers should expediently be above of 10,000, preferably between 15,000 and 200,000.

The quantitative ratio of optical brighteners / water-soluble polymer can be between 10: 1 and 1:10, preferably between 5: 1 to 2: 1.

As surface-active substances that improve the dissolution, for lowering the viscosity of highly concentrated settings, for spontaneous ones Distribution and to increase the whitening rate can be added with are to use non-ionic and ionic surfactants2 such as anion-active, cation-active or amphoteric surfactants. A compilation of the ionic surfactants that can be used is in the Schwartz-Perry-Berch "Surface Active Agents and Detergents (Vol. 2 Interscience Publishers Inc. New York, 1958). The anion-active surfactants can be: Alkylsulfonates, as described above, pp. 61-71 Alkylarylsulfonates, such as they are described a.a.o. Pp. 78-100 fatty acid amide alkane sulfonates as described are loc. cit. p. 76 alkyl sulfuric acid ester salts, as they are described loc. P. 40-61 alkyl and alkyl phenol ether sulfonates, as they are described in DRP 605.973 Amphoteric compounds, e.g. alkylamine alkyl sulfonates, as described in DAS 1.020.144 are, alkylbenzimidazole sulfonates, as described in DAS 1.257.779, Cation-active products are mentioned above on pages 112-118.

Condensed aryl sulfonic acids can also be used, such as e.g. di-naphthalene-methane-sulfonic acids, condensation products from naphtholsulfonic acid, Cresol, formaldehyde and sodium bisulfite (Fiat Final Report No. 1013), diphenyl ether sulfonic acid and formaldehyde (US Patent 2,315,951), oxydiphenylsulfonic acid and formaldehyde, urea and phenol such as diphenolsulfonsulfonic acid and formaldehyde (DAS 1,113,457, 1,178,081).

The amounts of these ionic surfactants are through preliminary tests at the individual associations are determined, but they are preferably based on less than 10% to the amount of brightener. This means that these stakes are far below those otherwise Usual amounts of dispersant.

In the preparation of the association complexes to be used according to the invention the general procedure is to use approximately equimolar amounts of the whitening agent and the low molecular weight complexing agent combined and mechanically well mixed. If the complexing agent has a solid consistency at room temperature, it is recommended to melt the components together and then the solidified melt to shred. If the associate is not resistant to hydrolysis, the solvent can be used evaporate and use the residue. The brighteners can also be used in an inert, few polar solvents, e.g. gasoline, low chlorinated hydrocarbons.

inter alia, stirred together with the associating substances and after the formation of associations from the solvent, e.g. by filtration or centrifuging, to be freed.

But it is particularly advantageous to form the association complex with the possibly still moist brightener crude product, such as at the end of the manufacturing process is isolated from the filter press. It is omitted in this way further cost-generating operations, such as drying and shredding processes. The complex formation changes in color to red, green, yellow-green o with yellow shades, as well as with associations, one component of which is liquid, to be recognized by hardening of the initially sticky and viscous mass. The reaction time lies between a few Seconds and 24 hours and is very of the reaction conditions and the chemical structure of the components.

With the stable dispersions obtainable by the new process excellent lightening can be achieved on synthetic fiber materials, Whiteness is partly higher than that with conventional settings is attainable. In particular, these dispersions allow perfect, level Dyeing of bobbins, packages, etc., in brilliant white tones. On too Paper and cotton can be used to achieve very good lightening effects.

Furthermore, there is a very rapid distribution in the slurry of washing powders as well as improved whitening from washing liquors.

The new process for the preparation of the whitener dispersions is on Hand of the following examples explained in more detail: Be4wo, iel 1-50 g of an association of dimethylformamide and 5- (p-chlorophenyl-) 1- (p-sulfamidophenyl) -pyrazoline-2 im Molar ratio 1: 1 and 13.1 g of a commercially available polyvinylpyrrolidone are with 45 ml of water containing 2 ml of a 7.5% strength aqueous oleyl benzylaminoethane sulfonic acid contains, rubbed in a mortar.

The thin, finely divided dispersion becomes after standing for some time viscous. This thixotropy can be prevented if instead of water a Solution of 10 g of urea in 55 ml of water is used. The active ingredient content is 35.2% and can be adjusted as required by diluting with water.

The mean grain size diameter is 1.1 / u. Colorations with this preparation are carried out, give on polyacrylonitrile or polyamide fibers a brilliant, bluish white effect. Winding bodies such as Dye packages perfectly in a brilliant white shade.

When incorporating into washing powder, you get at 40u and one Exposure time of 10 minutes with a concentration of 50 mg / l a degree of whiteness according to the whiteness formula according to Berger of 116, compared to 111, as it is with a conventional one Dispersion of the optical brightener is obtained.

The associate used above is obtained in the following way: 67 g 3- (p-chlorophenyl) -1- (p-sulfamidophenyl) pyrazoline-2 (factory made) and 14.6 g dimethylformamide are given together, creating a sticky mass. Shaken overnight hardens them to greenish-yellow, hard chunks that are pulverized. The associate melts at 1900, but immediately solidifies again to melt again at 2280.

Example 2 5 g of 1- (dimethoxy-triazinyl) pyrene as a 1: 1 complex with dimethylformamide are equalized with 5 g of a 50% strength aqueous solution of a graft polymer Share Vin @@ acetate and polyethylene glycol 1550 and 6 g of a 50 are aqueous Urea solution rubbed in a mortar. A thin liquid dispersion is obtained with very good coloring properties; the achievable degree of whiteness on polyester fibers is above that of conventional formations.

Example 5 Instead of the 5- (p-chlorophenyl) -1 mentioned in Example 1 (p-suifamidophenyl) -pyrazolin-2 become 3- (4-chloropyrazolyl-) 7- (3-methylpyrazolyl) -coumarin, 3-phenyl-7- [2- (4-phenyl-5-methyl) -1.2.3-triazolyl] -coumarin or 4-methyl-7-diethylaminocoumarin used, dispersions with similarly good lightening effects receives.

Example 4 24 g of 3 (p-chlorophenyl) -1- (p-sulfamido) -pyrazoline- (2). Dimethylformamide are with 20 g of a 15 point aqueous solution of polyacrylamide and 5 ml of a 50% aqueous urea solution ground in a mortar. The dispersion contains Particles with a mean diameter of 15yu.

A dispersion of 34 percent by weight optical brightener that does not is present as a complex, and provides 8.2 percent by weight of the same polymer analogously treats an average particle diameter of only 3.1 µ.

Instead of polyacrylamide, polyvinyl acetamide can be used with the same effect use.

Example 5 24 g of 7fp-chlorophenyl) - (p-sulfamidophenyl) -p -dimethylformamide with 2Q g of a 16 own aqueous solution -, 9 g of polyacrylic acid glycol ester and 5 g of water rubbed in a mortar. Dispersions are obtained in this way with a mean particle diameter of 1.0 / u, with which, for example achieve excellent whitening effects on polyacrylonitrile. Instead of of the polyacrylic acid glycol ester can also be a copolymer of acrylic acid and oxypropyl acrylate, a copolymer of equal parts of acrylic acid and acrylamide and oxypropyl methacrylate or a polymer prepared according to the following procedure use: 100 parts of an equimolar copolymer of vinyl acetate and maleic anhydride are hydrolyzed in 200 parts of water at 800 C, a clear solution of the Acid form of the polymer arises.

Example 6 24 g of 3- (p-chlorophenyl) -1- (p-sulfamidophenyl) -pyrazoline-2 Dimethylformamide with 20 g of a 50 weight percent aqueous solution of a Polyethylene oxide graft polymer and 20 ml of a 50 percent strength by weight aqueous Urea solution intimately mixed. The mean particle diameter is 0.6 µ compared to 2.9 / u when unassociated optical brightener is used.

To prepare the graft polymer, a mixture of 100 is stirred Parts of polyethylene oxide (molecular weight about 1,500) and a mixture of 67 parts of vinyl acetate and 55 parts of N-vinylpyrrolidone, in which 1 part of azodiisobutyronitrile is dissolved, under N2 20 hours at 750. Then 200 parts of water are added and receives a clear, aqueous 50% solution of the resulting graft polymer.

Those obtainable according to the above regulation can be obtained with the same effect Use polymers in which a) instead of vinyl acetate / N-vinylpyrrolidone Mixture of 100 parts of vinyl acetate, or b) a mixture of 50 parts each of vinyl acetate and N-vinyl pyrrolidone can be used.

Used in place of 100 parts of polyethylene oxide in the above regulation a diethylene glycol-formaldehyde-polyacetal with a molecular weight of approx. 1,300 is used, the mean grain diameter when using the association is l, l / u, at Use of the unassociated brightener 34'u. A delivers the same results Polymer in which instead of 100 parts of polyethylene oxide, 50 parts of diethylene glycol-formaldehyde-polyacetal with a molecular weight of approx. 1,300 can be used. Graft polymers can also be used from 50 parts of N-vinylpyrrolidone to 100 parts of polyethylene oxide 1,550 or the same Use parts of N-vinylpyrrolidone and polyethylene oxide 1.550.

Example 7 24 g of 3- (p-chlorophenyl) -1- (p-sulfoamidophenyl) -pyrazoline-2 .

Dimethylformamide with 20 g of a 30 percent by weight aqueous Solution of a reaction product of 1 part of an equimolar styrene-maleic anhydride copolymer with 1 part of 3-dimethylamino-1-aminopropane and 10 ml of a TO 50 strength aqueous urea solution rubbed in a mortar. The mean grain diameter of the dispersion is 0.4 µ.

Instead of 3-dimethylamino-1-aminopropane, comparable Effect in the above regulation diethanolamine are used'or polymers that obtained according to the following procedures: a) 300 parts of an equimolar copolymer from cyclohexyl maleate and styrene with a molecular weight of approx. 30,000 are at 800 C in 500 parts of an adduct of about 10 moles of ethylene oxide dissolved in 1 mole of isononylphenol and stirred for several hours. Then you sit down 55 parts of concentrated aqueous ammonia solution and 750 parts of water are added and obtained an approx. 50% well pourable solution - which can be used directly. The middle one Grain diameter of a dispersion with 44.5% optical brightener as dimethylformamide adduct and 77 ffi of the solution of the polymer is b) A mixture is placed in an autoclave introduced from: 400 parts of an equimolar copolymer of styrene and maleic anhydride, Molecular weight about 52,000, 220 parts of diethanol amine, 600 parts of adduct of approx. 14 moles of ethylene oxide in 1 mole of p-phenylphenol, 2,800 parts of water. Then heated one 10 hours at 1600 ° C. and, after cooling, a clear solution is obtained which directly can be used; Dry content approx. 30%.

c) As above, only a 10% aqueous ammonia solution is used instead of water used, i.e. an aqueous solution of the hemamidammon salt is formed.

Example 8 24 g of 3- (p-chlorophenyl) -1- (p-sulfamidophenyl) pyrazoline-2 Dimethylformamide with 20 g of a 15 own aqueous solution of a maleic acid polymer, ground with 10 ml of a 50 percent by weight aqueous urea solution for 1/2 hour. The mean grain size in the dispersion is 1.1 / u, but 2.5 / u if the Brightener was not used in association.

The 1: 1 complex of 3- (p-chlorophenyl) -1- (p-methoxycarbonylphenyl) pyrazoline-2 gives under the same conditions and dimethyl sulfoxide have a similarly good effect.

The polymer can be produced as follows: In an autoclave are introduced: 3,300 parts of water, 80 parts of NaOH, 546 parts of sulfanilic acid and 400 parts of an equimolar maleic anhydride-styrene copolymer with a molecular weight of approx. 80,000. The mixture is heated to 170 ° C. under No for 10 hours and a clear one is obtained Solution of the imide formed, which tends to gel on cooling. Most expedient this solution of the Na salt is diluted to a solids content of 15% and then used.

With a comparable effect one can also obtain those obtained in the following way Using polymers: a) In an autoclave are introduced: 800 parts of one equimolar styrene-maleic anhydride copolymer with a molecular weight of approx. 50,000, 2,800 parts of water, 400 parts of N-dimethyl-propylenediamine-1,3, 240 parts of acetic acid. The mixture is then heated to 1700 ° C. for 10 hours and, after cooling, a clear color is obtained Solution of the basic imide in the form of the acetate; b) In an autoclave are introduced: 800 parts of an equimolar styrene-maleic anhydride copolymer, 800 parts more concentrated. aqueous ammonia solution and 2,400 parts of water. One heats up 10 hours at 1700 C urS a slightly cloudy solution of the formed cyclic Imids that precipitate on acidification. The solution obtained becomes easier to handle diluted to a dry content of 10 percent by weight.

c) As above, only this time there will only be 200 parts of the primary-tertiary-diamine used and added 200 parts of cyclohexylamine. The amount of acetic acid is reduced to 70 parts. The resulting imide also forms a solution; it tends to gel and is therefore expediently diluted to 25% dry matter.

Example 9 Instead of the dimethylformamide mentioned in Example 1 the following low molecular weight complexing agents can also be used: monomethyl formamide, Dimethyl acetamide, phthalimide, N-8utyl phthalimide and tetrachlorophthalic acid.

This gives a dispersion with a content of 15 percent by weight of the graft polymer of 1 part of N-vinylpyrrolidone and 2 parts of vinyl acetate Polyethylene glycol 1,550 and 57 percent by weight brightener active ingredient a medium - Grain diameter with the associate of dimethyl acetamide 1.0 / us from monomethyl formamide 1.5 / u, off, dimethylformamide 0.6 µ, compared to 2.8 for unassociated brightener.

The whiteness of the lightening and the properties of the dispersion - are correct with the data given in Example 1 agree.

ie110 Instead of oleylbenzylaminoethane sulfonic acid in example 1 -can be used as surfactants or dispersants in the presence of polyacrylic acid glycol ester, which takes the place of the polyvinylpyrrolidone mentioned in Example 1, -following Compounds used are: bis (hydroxydiphenyl ether) methane sulfonic acid, bis (hydroxytrimethylene) urea, Diisobutyl naphthalene sulfonate.

The degree of whiteness and properties of the dispersion correspond to those in the example 1 given data.

Example 11 instead of oleylbenzylaminoethanesulfonic acid in example 1 can be selected as surfactants or dispersants in the presence of the reaction product an equimolar maleic anhydride "styrene copolymer and sulfanilic acid, the The following compounds take the place of the polyvinylpyrrolidone mentioned in Example 1 are used: Glycerin-1,9- bis- (2-ethylhexyl ether) -2, sulfuric acid ester, stearylbenzylaminopropanesulfonic acid, Oleyl alcohol polyglycol ether (16 mol ethylene oxide), sucrose polypropyl ethyl ether (10 moles of polypropylene, 8 moles of ethylene oxide). Degree of whiteness and properties of the dispersion correspond to the data given in Example 1.

Example 12 Instead of oleylbenzylaminoethane sulfonic acid in example 1 can be used as surfactants or dispersants in the presence of a graft polymer of 1 part of N-vinylpyrrolidone and 2 parts of vinyl acetate to 5 parts of polyethylene oxide 1.550, which takes the place of the polyvinylpyrrolidone mentioned in Example 1, the following compounds are used: bis-diphenyl ether methanesulfonate, sucrose polypropyl ätllyläther (iO mol propylene oxide, 8 mol ethylene oxide), dodecyl-benzyldimethyl-ammonium chloride, Glycerine 1,3 bis (2-ethylhexyl ether) -2, sulfuric acid ester, sulfation products the compound given in the German Patent SchrtSt 740.104 in Example 4.

Claims (15)

Claims 1) Process for the preparation of stable aqueous dispersions of in Water-poorly soluble optical brighteners, characterized in that they are association complexes from these brighteners and low molecular weight complexing agents in optionally surface-active Aqueous solutions of polymeric compounds containing agents enters. 2) Method according to claim 1, characterized in that as optical brighteners are used whose association complexes with 1,5-dinitrobenzene in a dioxane solution, which the brightener in 10-3 molar and 1,3-dinitrobenzene Contains 2.7 molar concentration, at 20 ° C and a layer thickness of 1 cm have a JSm value between 5w10) and 600-10. 3) Method according to claim 1, characterized in that as optical brighteners are used whose water solubility is below 5 g / l. 4) Method according to claim 1, characterized in that as Brighteners from the series of diarylpyrazolines,) -aryl and 5-heteryl-carbostyriles, 5-aryl- and 3-heteryl-coumarins, triazinylpyrene, bis -benzoimidazo lyläthylene, Bis-benzoxazolylthiophenes, bis-benzoxazolylstilbenes, styrylbenzoxazoles and bis-triazinylstilbenes used. 5) Method according to claim 1, characterized in that as low molecular complexing agents carboxamides, carboximides, ureas, Sulphoxides or unsaturated, carboxylic acid @ used. 6) Method according to claims 1 and 4, characterized in that that is used as a low molecular weight complexing agent Di methylformamide. 7) Method according to claims 1 and 4, characterized in that that the optical brightener is an unground, possibly still moist brightener raw product begins. 8) method according to claim 1, characterized in that as water-soluble polymeric compounds vinyl polymers, graft polymers of vinyl compounds on polyethers and / or polyacetals or homo- and copolymers of maleic acid and their derivatives are used. 9) Method according to claims 1 and 8, characterized in that that the water-soluble vinyl polymers are polyvinylpyrrolidone or polyhydroxyethyiacrylate used. lO) Process according to claims 1 and 8, characterized in that that the water-soluble graft polymers are those of vinyl acetate and / or vinylpyrrolidone on polyethers made from ethylene oxide and / or propylene oxide or polyacetals made from di- and / or Triethylene glycol and formaldehyde are used. 11) VerSwren according to claims 1 and 8, characterized in that that the water-soluble maleic acid polymers are homopolymers and copolymers of the Maleic acid half-esters and / or half-amides used. 12) Method according to claim 1, characterized in that the quantitative ratio between optical brightener and polymeric compounds is between 10: 1 and 1:10. 13) Stable aqueous dispersions, prepared according to the procedures according to of claims 1-11. 14) 'Process for the optical brightening of textile materials, thereby characterized in that dispersions prepared according to claims 1-11 are used. 15) With dispersions, prepared according to claims 1-11, lightened Textile materials.