EP0030917B1 - Optical brighteners from bistyryl benzene, process for their preparation and their use - Google Patents

Description

The present invention relates to optical brighteners consisting of two bis-styrylbenzene compounds, to a process for their preparation and to the intermediates which occur in the process, agents containing such optical brighteners and the use of these optical brighteners or the agents containing them for the optical brightening of organic high-molecular materials .

A large number of bis-styrylbenzene compounds and their use as optical brighteners for various substrates are known from the literature, see CH-A-366 512, 382 709 388 294, 388 929, 389 585, 411 329, 416 078 and 465 548 Some individual components which are contained in the composite optical brighteners according to the invention are disclosed in the cited documents, such as, for example, B. 1,4-bis (2-, 3- or 4-cyanostyryl) benzene or 1,4-bis (4-methoxycarbonylstyryl) benzene. Some of these compounds are also commercially available. Mixtures of 1,4-bis-styrylbenzene compounds are also known which consist of three components, namely about 50% of one asymmetrically substituted and about 25% each of two different symmetrically substituted bis-styrylbenzene compounds. Such mixtures arise purely statistically when reacting one mole of terephthalaldehyde with a mixture of one mole each of two optionally substituted benzylphosphonates.

Mixtures of two or more symmetrically substituted bis-styrylbenzenes are also known, which can be obtained by simply mixing pure symmetrical compounds.

The use of the mixtures just described as optical brighteners for various organic substrates, especially of polyester, is also known, see CH-A-366512, 382 709.416 078 and 465 548.

Further mixtures of three bis-styrylbenzene compounds are known from CH-A-366512 and 382 709. Such mixtures are obtained by simultaneous reaction of terephthalaldehyde with a mixture of 50-98, especially 80-87%, a substituted benzylphosphonate and 50-2, especially 20-3% of such a differently substituted benzylphosphonate.

However, due to the production process, these known three-component mixtures mentioned can contain at most about 50% of the respective asymmetrically substituted bis-styrylbenzene compound.

It has now surprisingly been found that an optical brightener consisting of 51-99% by weight, preferably 80-99% by weight, in particular 90-99% by weight, of an asymmetrically substituted 1,4-bis-styrylbenzene compound and 49-1% by weight, preferably 20-1% by weight, in particular 10-1% by weight, of a symmetrically substituted 1,4-bis-styrylbenzene compound is able to achieve significantly higher brightening effects than the known corresponding individual compounds and those above mentioned mixtures.

In addition, this composite brightener can be produced very well by the new method according to the invention.

worin Rund R_i gleich oder verschieden sind, worin für den Fall, daß Rund R, gleich sind, R_i eine andere Position im Phenylring, an den es gebunden ist, besetzen muß als R in seinem Phenylring und worin R und R₁ unabhängig voneinander CN oder eine gegebenenfalls substituierte Carbonsäureestergruppe bedeuten, und 49-1 Gew.-% einer symmetrisch substituierten Verbindung der Formel

worin R die obige Bedeutung hat und beide R in ihren Phenylringen an die gleiche Position gebunden sind.The optical brightener according to the invention consists of 51-99% by weight of an asymmetrically substituted compound of the formula

where R _{i are the} same or different, where in the case where R _{i are the} same, R _i must occupy a different position in the phenyl ring to which it is attached than R in its phenyl ring and where R and R _{1 are} independent of one another CN or an optionally substituted carboxylic acid ester group, and 49-1 wt .-% of a symmetrically substituted compound of the formula

where R has the above meaning and both R are attached to the same position in their phenyl rings.

The bis-styrylbenzene compound (1) must therefore be unsymmetrically substituted in any case. The substituents R and R _i , regardless of whether they are the same or different, are preferably attached to different positions of the respective phenyl ring. The compound (2) is symmetrical both with regard to the substituent R and with regard to its position.

bedeutet, wobei in der letztgenannten Gruppe X für Wasserstoff oder Methyl und n für eine Zahl zwischen 1 und 4 stehen und die Alkylgruppe 1 bis 6 Kohlenstoffatome aufweist. Unter Halogen ist Chlor, Brom und Fluor, insbesondere Chlor oder Brom zu verstehen. Die Substituenten Halogenalkyl und Hydroxyalkyl können ein oder mehrere Halogenatome bzw. eine oder mehrere Hydroxylgruppen enthalten.Preferred carboxylic ester groups are those of the formula -COOY, in which Y is alkyl having 1 to 6 carbon atoms, alkenyl having 3 to 6 carbon atoms, cycloalkyl having 5 or 6 carbon atoms atoms, haloalkyl, aralkyl, especially phenylalkyl, especially benzyl, carbalkoxyalkyl, cyanoalkyl, hydroxyalkyl, aminoalkyl, alkylaminoalkyl, dialkylaminoalkyl, it being possible for all of the composite alkyl groups mentioned above to have 1 to 6 carbon atoms in each alkyl part; Propargyl, tetrahydrofurfuryl or a group of the formula

means, where in the latter group X is hydrogen or methyl and n is a number between 1 and 4 and the alkyl group has 1 to 6 carbon atoms. Halogen means chlorine, bromine and fluorine, in particular chlorine or bromine. The substituents haloalkyl and hydroxyalkyl can contain one or more halogen atoms or one or more hydroxyl groups.

Y particularly preferably represents alkyl having 1 to 6, in particular 1 to 4, carbon atoms, alkenyl with 3 to 6 carbon atoms and benzyl, especially alkyl with 1 to 4 carbon atoms. All alkyl groups belonging to compound groups (which form the substituent Y) preferably have 1 to 4 carbon atoms.

Optical brighteners according to the invention, in which the individual components R and R are the same and each denote CN, have particularly good properties.

und 49-1 Gew.-% der Verbindung der Formel

sowie aus 51-99 Gew.-% der Verbindung der Formel

und 49-1 Gew.-% der Verbindung der Formel

Of particular practical interest are the two optical brighteners consisting of 51-99% by weight of the compound of the formula

and 49-1% by weight of the compound of the formula

and from 51-99% by weight of the compound of the formula

and 49-1% by weight of the compound of the formula

The optical brighteners according to the invention have particularly valuable properties if they consist of 70-99, in particular 80-99, but especially 90-99% by weight of the asymmetrically substituted compound, for. B. of the formula (1) or (3), and 30-1, in particular 20-1, but especially 10-1 wt .-% of the symmetrically substituted compound, for. B. of the formula (2), (4) or (6).

Particularly noteworthy is the optical brightener, consisting of 90-99% by weight of the compound of formula (3) and 10-1% by weight of the compound of formula (4) and that consisting of 90-99% by weight. the compound of formula (3) and 10-1% by weight of the compound of formula (6).

Unless stated otherwise, all percentages in this application are based on weight.

The optical brighteners according to the invention are produced by a new process which is also the subject of the invention.

In the discussion of the known bis-styrylbenzenes and the known mixtures thereof, the processes which lead to such mixtures (statistical mixtures of 3 components) have already been discussed. Furthermore, it is known from DE-A-2 647 179 how 2'-cyanostilben-4-aldehyde, which occurs as an intermediate in the process according to the invention, can be obtained in pure form using a multistage synthesis. In this publication, see page 25, last paragraph to page 27, first paragraph: Preparation of the starting compound (3).

It has surprisingly been found that the optical brighteners according to the invention consist of two individual components can be produced by a very simple synthesis process.

zu einem Gemisch der Verbindungen der Formeln

und

umsetzt und dieses Gemisch dann weiter in Gegenwart eines alkalischen Kondensationsmittels mit einer Verbindung der Formel

zu dem Aufheller bestehend aus den Verbindungen (1) und (2) umsetzt, wobei R und R, die in Formeln (1) und (2) angegebenen Bedeutungen haben und die dort angegebenen Bedingungen bezüglich ihrer Stellungen in den Phenylringen erfüllen müssen und wobei X und Y gleich oder verschieden sind und unabhängig voneinander einen Rest der Formel

oder

bedeuten, und wobei das Mengenverhältnis zwischen Terephthalaldehyd und der Verbindung der Formel (7) so gewählt wird, daß das Verhältnis zwischen symmetrischer und unsymmetrischer Komponente im Endprodukt im oben für die Verbindungen der Formeln (1) und (2) angegebenen Bereich liegt.The process according to the invention is characterized in that terephthalaldehyde in the presence of an alkaline condensing agent with a compound of the formula

to a mixture of the compounds of the formulas

and

and this mixture is then reacted further in the presence of an alkaline condensing agent with a compound of the formula

to the brightener consisting of the compounds (1) and (2), where R and R, which have the meanings given in formulas (1) and (2) and have to meet the conditions specified there with regard to their positions in the phenyl rings, and where X and Y are the same or different and independently of one another are a radical of the formula

or

mean, and wherein the quantitative ratio between terephthalaldehyde and the compound of formula (7) is chosen so that the ratio between symmetrical and asymmetrical component in the end product is in the range given above for the compounds of formulas (1) and (2).

The quantitative ratio between terephthalaldehyde and the compound of formula (7) thus depends on which quantitative ratio is desired in the final mixture of asymmetrically and symmetrically substituted bis-styrylbenzenes. Accordingly, the quantitative ratio between the monoaldehyde (8) and the compound of formula (9) reacting therewith can be adjusted. In this way, each quantitative ratio defined above for the compounds of the formulas (1) and (2) can be set by the choice of the quantitative ratios in the starting products. The content of monoaldehyde (8) in the reaction mixture can easily be determined analytically will.

The reaction is preferably carried out with compounds of the formulas (7) and (9) in which X and Y each represent a group of the formula (12). In the formulas (10) to (13), alkyl preferably denotes an unsubstituted alkyl group having 1 to 6 carbon atoms or the benzyl group and aryl, preferably phenyl, optionally substituted with chlorine, methyl or methoxy.

bzw.

zu einem Gemisch der Verbindungen der Formel

und der Formel (4) bzw. zu einem Gemisch der Verbindungen der Formel

und der Formel (6) umsetzt und das jeweils erhaltene Gemisch anschließend mit einer Verbindung der Formel

bzw.

zu den erfindungsgemäßen optischen Aufhellern bestehend aus den Verbindungen der Formeln (3) und (4) bzw. (3) und (6) umsetzt.A preferred implementation in the process of the invention is characterized in that terephthalaldehyde with a compound of the formula

respectively.

to a mixture of the compounds of the formula

and of the formula (4) or to a mixture of the compounds of the formula

and the formula (6) and then reacting the mixture obtained in each case with a compound of the formula

respectively.

to the optical brighteners according to the invention consisting of the compounds of the formulas (3) and (4) or (3) and (6).

The reaction of terephthalaldehyde with a compound of the formula (7) or with a compound of the formula (14) or (15) (first stage) is carried out in the presence of an alkaline condensing agent which serves as a proton acceptor. Such condensation agents are inorganic or organic bases, for. B. hydroxides, hydrides, alkoxides and amides of alkali or alkaline earth metals, monomeric or polymeric strongly basic amines and resin exchangers OH series in question. Sodium and potassium hydroxide and sodium methylate are of particular practical importance. A mixture of different bases can also be used. The amount of condensing agent to be used is within wide limits. The equivalent amount is advantageously used, but an excess can also be used. The second stage (reaction of the mixture of monoaldehyde and symmetrical bis-styrylbenzene compound) is also carried out in the presence of an alkaline condensing agent.

The process according to the invention is expediently carried out in a solvent which is inert under the reaction conditions. As such solvents come apolar and dipolar aprotic and protic solvents such as. B. hexane, octane, cyclohexane, toluene, xylene, chlorobenzene, etc; Formamide, dimethylformamide, N-methylpyrrolidone, acetonitrile, dimethyl sulfoxide, etc .; Methanol, ethanol, isopropanol, hexanol, etc. into consideration. The process of the invention can also be carried out in water or in water-containing mixtures in the presence or absence of phase transfer catalysts.

The first stage is preferably in a solvent in which the resulting monoaldehydes of the formulas (8) or (16) and (17) are sparingly soluble, such as, for. B. in methanol, ethanol, hexane or toluene. The aldehydes formed precipitate during the reaction together with the symmetrical compounds of the formulas (2) or (4) and (6) and can be isolated by filtration or, preferably, can be reacted further without isolation. If the mixtures obtained are isolated, they are preferably used further without purification.

The reaction of the monoaldehydes of the formulas (8) or (16) and (17), as mixtures together with the symmetrical compounds of the formulas (2) or (4) and (6), with a compound of the formula (9) or (15) or (14) (second stage) is preferably carried out in a solvent in which the monoaldehydes are partially or completely soluble. As such solvents come aprotic dipolar solvents such as. B. dimethyl and diethylformamide and dimethyl sulfoxide in question.

The reaction temperature varies within wide limits depending on the solvent selected and can easily be determined by preliminary tests. The first stage is expediently carried out at temperatures between 0 ° C. and 50 ° C., preferably between 20 ° C. and 30 ° C. Temperatures between 20 ° C. and 100 ° C., preferably between 30 ° C. and 50 ° C., are particularly suitable for the second stage.

The compounds of the formulas (7) and (9) used as starting products are known or can be used analogously to known processes (see, for example, DE-A-1 921 466, GB-A-920 988 and 929436) or according to the example below 14 (manufacture of the starting product).

im Gemisch mit Stilbenverbindungen der Formel

worin R₂' Cyano oder eine Carbonsäureestergruppe, insbesondere eine solche der Formel -COOY bedeutet, worin Y Alkyl, Halogenalkyl, Aralkyl, Carbalkoxyalkyl, Cyanoalkyl, Hydroxyalkyl, Aminoalkyl, Alkylaminoalkyl, Dialkylaminoalkyl, wobei alle vorgenannten Alkylgruppen und Alkylteile in zusammengesetzten Gruppen jeweils 1 bis 6 Kohlenstoffatome aufweisen; Alkenyl mit 3 bis 6 Kohlenstoffatomen, Cycloalkyl mit 5 bis 6 Kohlenstoffatomen, Propargyl, Tetrahydrofurfuryl oder eine Gruppe der Formel

darstellt, worin X für Wasserstoff oder Methyl und n für eine ganze Zahl zwischen 1 und 4 stehen und die Alkylgruppe 1 bis 6 Kohlenstoffatome aufweist, das dadurch gekennzeichnet ist, daß man Terephthalaldehyd mit einer Verbindung der Formel

in einem Lösungsmittel, in dem der Stilbenaldehyd schwer löslich ist und in Gegenwart eines alkalischen Kondensationsmittels umsetzt, worin X' einen Rest der Formel

bedeutet. Zur Isolierung des Stilbenaldehyds aus dem erhaltenen Gemisch kann man den Aldehyd durch gegebenenfalls mehrmalige Umkristallisation oder durch Chromatographie abtrennen.The invention further relates to a process for the preparation of the stilbenaldehydes of the formula which occur as intermediates

in a mixture with stilbene compounds of the formula

wherein R ₂ 'cyano or a carboxylic acid ester group, in particular one of the formula -COOY, wherein Y is alkyl, haloalkyl, aralkyl, carbalkoxyalkyl, cyanoalkyl, hydroxyalkyl, aminoalkyl, alkylaminoalkyl, dialkylaminoalkyl, all of the above-mentioned alkyl groups and alkyl parts in composite groups in each case 1 to Have 6 carbon atoms; Alkenyl with 3 to 6 carbon atoms, cycloalkyl with 5 to 6 carbon atoms, propargyl, tetrahydrofurfuryl or a group of the formula

represents in which X is hydrogen or methyl and n is an integer between 1 and 4 and the alkyl group has 1 to 6 carbon atoms, which is characterized in that terephthalaldehyde with a compound of formula

in a solvent in which the stilbenaldehyde is sparingly soluble and reacts in the presence of an alkaline condensing agent, wherein X 'is a radical of the formula

means. To isolate the stilbenaldehyde from the mixture obtained, the aldehyde can be separated off by repeated recrystallization, if necessary, or by chromatography.

The reaction is carried out in the presence of an alkaline condensing agent in a solvent in which the stilbene aldehydes are sparingly soluble. Examples of such condensing agents and solvents are given above in the description of the first stage of the process for the preparation of the brightener mixtures. Preferred temperature ranges and preferred compounds of formula (24) correspond to those described for the first step mentioned. The purification of the aldehydes is conveniently carried out by chromatography, for. B. column chromatography or preferably by recrystallization, if necessary by multiple recrystallization, optionally with the addition of activated carbon or bleaching earth. Dioxane is preferred as the solvent for the recrystallization.

Using the process according to the invention, the stilbenaldehydes mentioned can be reached in one step in a very simple manner, while according to DE-A-2 647 179 (see above), stilbenaldehydes can only be obtained via a complicated, multi-stage synthesis.

The optical brighteners according to the invention are used for optically brightening a wide variety of synthetic, semi-synthetic or natural organic materials.

• I. Synthetische organische hochmolekulare Materialien:
  • a) Polymerisationsprodukte auf Basis mindestens eine polymerisierbare Kohlenstoff-Kohlenstoff-Doppelbindung enthaltender organischer Verbindungen, d. h. deren Homo- oder Copolymerisate sowie deren Nachbehandlungsprodukte wie beispielsweise Vernetzungs-, Pfropfungs- oder Abbauprodukte, Polymerisat-Verschnitte oder durch Modifizierung reaktionsfähiger Gruppen erhaltene Produkte, beispielsweise Polymerisate auf Basis von a,,8-ungesättigten Carbonsäuren oder Derivaten solcher Carbonsäuren, insbesondere von Acrylverbindungen (wie z. B. Acrylestern, Acrylsäure, Acrylnitril, Acrylamiden und deren Derivaten oder deren Methacryl-Analoga), von Olefin-Kohlenwasserstoffen (wie z. B. Äthylen, Propylen, Styrole oder Diene, ferner sogenannte ABS-Polymerisate), Polymerisate auf Basis von Vinyl- und Vinyliden-Verbindungen (wie z. B. Vinylchlorid, Vinylalkohol, Vinylidenchlorid),
  • b) Polymerisationsprodukte, die durch Ringöffnung erhältlich sind, z. B. Polyamide vom Polycaprolactam-Typ, ferner Polymere, die sowohl über Polyaddition als auch Polykondensation erhältlich sind, wie Polyäther oder Polyacetale,
  • c) Polykondensationsprodukte oder Vorkondensate auf Basis bi- oder polyfunktioneller Verbindungen mit kondensationsfähigen Gruppen, deren Homo- und Mischkondensationsprodukte sowie Produkte der Nachbehandlung, wie beispielsweise Polyester, insbesondere gesättigte (z. B. Äthylenglykolterephthalsäure-Polyester) oder ungesättigte (z. B. Maleinsäure-Dialkohol-Polykondensate sowie deren Vernetzungsprodukte mit anpolymerisierbaren Vinylmonomeren), unverzweigte sowie verzweigte (auch auf Basis höherwertiger Alkohole, wie z. B. Alkydharze) Polyester, Polyamide (z. B. Hexamethylendiamin-adipat), Maleinatharze, Melaminharze, deren Vorkondensate und Analoga, Polycarbonate, Silicone,
  • d) Polyadditionsprodukte wie Polyurethane (vernetzt und unvernetzt), Epoxidharze.
• 11. Halbsynthetische organische Materialien, z. B. Celluloseester verschiedener Veresterungsgrade (sogenanntes 2¹/₂-Acetat, Triacetat) oder Celluloseäther, regenerierte Cellulose (Viskose, Kupferammoniak-Cellulose) oder deren Nachbehandlungsprodukte, Casein-Kunststoffe.
• 111. Natürliche organische Materialien animalischen oder vegetabilischen Ursprungs, beispielsweise auf Basis von Cellulose oder Proteinen wie Baumwolle, Wolle, Leinen, Seide, natürliche Lackharze, Stärke, Casein.

For this purpose, the following groups of organic materials, to the extent that they can be optically brightened, may be mentioned, for example, without being restricted to the following overview:

• I. Synthetic organic high molecular materials:
  • a) Polymerization products based on organic compounds containing at least one polymerizable carbon-carbon double bond, ie their homopolymers or copolymers and their aftertreatment products such as crosslinking, grafting or degradation products, polymer blends or products obtained by modifying reactive groups, for example polymers Basis of a ,, 8-unsaturated carboxylic acids or derivatives of such carboxylic acids, in particular of acrylic compounds (such as acrylic esters, acrylic acid, acrylonitrile, acrylamides and their derivatives or their methacrylic analogues), of olefin hydrocarbons (such as Ethylene, propylene, styrenes or dienes, furthermore so-called ABS polymers), polymers based on vinyl and vinylidene compounds (such as vinyl chloride, vinyl alcohol, vinylidene chloride),
  • b) polymerization products obtainable by ring opening, e.g. B. polyamides of the polycaprolactam type, also polymers which are available both via polyaddition and polycondensation, such as polyethers or polyacetals,
  • c) polycondensation products or precondensates based on bifunctional or polyfunctional compounds with groups capable of condensation, their homo- and mixed condensation products and products of aftertreatment, such as polyesters, in particular saturated (e.g. ethylene glycol terephthalic acid polyesters) or unsaturated (e.g. maleic acid) Dialcohol polycondensates and their crosslinking products with polymerizable vinyl monomers), unbranched and branched (also based on higher alcohols, such as alkyd resins) polyesters, polyamides (e.g. hexamethylenediamine adipate), maleate resins, melamine resins, their precondensates and analogues, Polycarbonates, silicones,
  • d) polyaddition products such as polyurethanes (crosslinked and uncrosslinked), epoxy resins.
• 11. Semi-synthetic organic materials, e.g. B. Celluloseester various degrees of esterification (so-called 2 _^1/2 acetate, triacetate), or cellulose ethers, regenerated cellulose (viscose rayon, cuprammonium cellulose) or its post-treatment products, casein plastics.
• 111. Natural organic materials of animal or vegetable origin, for example based on cellulose or proteins such as cotton, wool, linen, silk, natural varnish resins, starch, casein.

The organic materials to be optically brightened can belong to the most varied of processing states (raw materials, semi-finished or finished products). On the other hand, they can be in the form of a wide variety of shaped structures, that is, for example, predominantly three-dimensionally extended bodies such as plates, profiles, injection moldings, various types of workpieces, chips, granules or foams, furthermore as predominantly two-dimensional bodies such as films, foils, lacquers, coatings, impregnations and coatings or as predominantly one-dimensional bodies such as threads, fibers, flakes, Wires. Said materials, on the other hand, can also be in unshaped states in a wide variety of homogeneous or inhomogeneous forms of distribution, such as. B. as powders, solutions, emulsions, dispersions, latices, pastes or waxes.

Fiber materials can be, for example, as endless threads (drawn or undrawn), staple fibers, flakes, extrudates, textile threads, yarns, threads, non-woven fabrics, felts, wadding, flocking structures or as textile fabrics or textile composites, knitted fabrics, and as papers, cardboards or paper pulps are available.

The brighteners to be used according to the invention are of particular importance for the treatment of textile organic materials, in particular textile fabrics. If fibers which can be in the form of staple fibers or continuous threads, in the form of strands, fabrics, knitted fabrics, nonwovens, flocked substrates or composites, are to be optically brightened according to the invention, this is advantageously done in an aqueous medium in which the compounds in question are in finely divided form (suspensions, so-called microdispersions, optionally solutions) are present. If necessary, dispersants, stabilizers, wetting agents and other auxiliaries can be added during the treatment.

When applying, you can work in neutral, alkaline or acid bath. The treatment is usually carried out at temperatures of approximately 20 to 140 ° C., for example at the boiling point of the bath or in the vicinity thereof (approximately 90 ° C.). For the finishing of textile substrates according to the invention, solutions or emulsions in organic solvents are also suitable, as is practiced in dyeing practice in so-called solvent dyeing (pad heat-setting application, exhaust dyeing process in dyeing machines).

The optical brighteners according to the present invention can also be added to or incorporated into the materials before or during their deformation. They can be added to the molding compound or injection molding compound, for example, in the production of films, foils (for example hot rolling in polyvinyl chloride) or moldings.

• - Zugabe zu den Ausgangssubstanzen (z. B. Monomeren) oder Zwischenprodukten (z. B. Vorkondensaten, Präpolymeren), d. h. vor oder während der Polymerisation, Polykondensation oder Polyaddition,
• - Aufpudern auf Polymerisatschnitzel oder Granulate für Spinnmassen,
• - Badfärbung von Polymerisatschnitzeln oder Granulaten für Spinnmassen,
• - Dosierte Zugabe zu Spinnschmelzen oder Spinnlösungen,
• - Applikation auf Spinnkabel vor dem Verstrecken.

If fully or semi-synthetic organic materials are shaped by spinning processes or spinning masses, the optical brighteners can be applied by the following processes:

• Addition to the starting substances (e.g. monomers) or intermediates (e.g. precondensates, prepolymers), ie before or during the polymerization, polycondensation or polyaddition,
• - powdering onto polymer chips or granules for spinning masses,
• - bath coloring of polymer chips or granules for spinning masses,
• - metered addition to spinning melts or spinning solutions,
• - Application on spinning cable before stretching.

• a) Mischungen mit Farbstoffen (Nuancierung) oder Pigmenten (Farb- oder insbesondere z. B. Weißpigmenten) oder als Zusatz zu Färbebädern, Druck-, Ätz- oder Reservepasten, ferner auch zur Nachbehandlung von Färbungen, Drucken oder Ätzdrucken,
• b) in Mischungen mit sogenannten »Carriern«, Netzmitteln, Weichmachern, Quellmitteln, Antioxydantien, Lichtschutzmitteln, Hitzestabilisatoren, chemischen Bleichmitteln (Chlorit-Bleiche, Bleichbäder-Zusätze),
• c) in Mischung mit Vernetzern, Appreturmitteln (z. B. Stärke oder synthetischen Appreturen) sowie in Kombination mit den verschiedensten Textilveredlungsverfahren, insbesondere Kunstharzausrüstungen (z. B. Knitterfest-Ausrüstungen wie »wash-and-wear«, »permanent-press«, »noniron«), ferner Flammfest-, Weichgriff-, Schmutzablöse (»anti-soiling«)- oder Antistatisch-Ausrüstungen oder antimikrobiellen Ausrüstungen,
• d) Einarbeiten der optischen Aufhellmittel in polymere Trägermaterialien (Polymerisations-, Polykondensations- oder Polyadditionsprodukte) in gelöster oder dispergierter Form für Anwendung z. B. in Beschichtungs-, Imprägnier- oder Bindemitteln (Lösungen, Dispersionen, Emulsionen) für Textilien, Vliese, Papier, Leder,
• e) als Zusätze zu den verschiedensten industriellen Produkten, um dieselben marktfähiger zu machen (z. B. Aspektverbesserung von Seifen, Waschmitteln, Pigmenten),
• f) in Spinnbadpräparationen, d. h. als Zusätze zu Spinnbädern, wie sie zur Gleitfähigkeitsverbesserung für die Weiterverarbeitung von Synthese-Fasern verwendet werden, oder aus einem speziellen Bad vor der Verstreckung der Faser,
• g) in Mitteln zum optischen Aufhellen von hochmolekularen organischen Materialien der vorstehend angegebenen Zusammensetzungen, welche Mittel gegebenenfalls übliche Formulierungszusätze und/oder gegebenenfalls weitere optische Aufheller aus anderen Aufhellerklassen enthalten,
• h) als Scintillatoren, für verschiedene Zwecke photographischer Art, wie z. B. für elektrophotographische Reproduktion und Supersensibilisierung,
• j) je nach Substitution als Laser-Farbstoffe.

The optical brighteners according to the invention can also be used, for example, in the following application forms:

• a) Mixtures with dyes (shading) or pigments (dyes or, in particular, for example, white pigments) or as an additive to dye baths, printing pastes, etching pastes or reserve pastes, and also for post-treatment of dyeings, prints or etching prints,
• b) in mixtures with so-called »carriers«, wetting agents, plasticizers, swelling agents, antioxidants, light stabilizers, heat stabilizers, chemical bleaching agents (chlorite bleach, bleach bath additives),
• c) in a mixture with crosslinking agents, finishing agents (e.g. starch or synthetic finishes) as well as in combination with a wide variety of textile finishing processes, in particular synthetic resin finishing (e.g. wrinkle-resistant finishing such as "wash-and-wear", "permanent-press" , "Noniron"), furthermore flame-resistant, soft-grip, dirt ("anti-soiling") or antistatic or antimicrobial equipment,
• d) Incorporation of the optical brighteners in polymeric carrier materials (polymerization, polycondensation or polyaddition products) in dissolved or dispersed form for use, for. B. in coating, impregnating or binding agents (solutions, dispersions, emulsions) for textiles, nonwovens, paper, leather,
• e) as additives to a wide variety of industrial products in order to make them more marketable (e.g. improving aspects of soaps, detergents, pigments),
• f) in spin bath preparations, ie as additives to spin baths, such as those used to improve the slidability for the further processing of synthetic fibers, or from a special bath before drawing the fiber,
• g) in agents for optically brightening high molecular weight organic materials of the above specified compositions, which agents optionally contain customary formulation additives and / or optionally further optical brighteners from other brightener classes,
• h) as scintillators, for various purposes of a photographic nature, such as. B. for electrophotographic reproduction and supersensitization,
• j) depending on the substitution as laser dyes.

Such agents, which contain the optical brighteners according to the invention, are also the subject of the invention.

As usual formulation additives come e.g. B. various auxiliaries and Coupiermittel such. B. anhydrous sodium sulfate, sodium sulfate decahydrate, sodium chloride, sodium carbonate, alkali metal phosphates such as sodium or potassium orthophosphate, sodium or potassium pyrophosphate and sodium or potassium tripolyphosphates or alkali metal silicates into consideration. But aqueous formulations also fall under the agents according to the invention, e.g. B. also the application solutions with which textile fibers are optically brightened and which contain the usual additives.

Particularly preferred within the scope of the agents according to the invention are those which, in addition to an optical brightener according to the invention which produces a greenish to bluish shade on the substrate to be treated (e.g. mixtures of the compounds (1) and (2), (3) and (4 ) or (3) and (6)) additionally contain an optical brightener, which produces a reddish shade on the substrate to be treated.

Such combinations have the advantage that a particularly beautiful neutral white shade of high brilliance can be achieved on textile fibers, especially on polyester fibers.

Means which have an optical brightener consisting of the compounds (3) and (4) or (3) and (6) or other mixtures of a symmetrical and asymmetrical component from which the brighteners according to the invention consist and additionally an optical brightener are therefore very advantageous from the class of naphthalimides, bis-benzoxazolyl-ethylenes, bis-benzoxazolyl-thiophenes, stilbenylbenzoxazoles, naphthotriazol-2-yl-stilbenes (known from DE-A-2 539 537 and 2539461) or coumarins, e.g. B. the 3-phenyl-7-pyrazolylcoumarins, the 3-pyrazolyl-7-v-triazolylcoumarins or the 3-v-triazolylcoumarins (known from CH-A-566 359 and 592 189), especially those which contain Brightener active substance 5-90% by weight, in particular 30-70% by weight, of an optical brightener according to the invention which produces a greenish to bluish shade on the treated substrate (for example mixtures of the compounds (1) and (2 ), (3) and (4) or (3) and (6)) and 95-10% by weight, in particular 70-30% by weight, of an optical brightener which produces a reddish shade on the treated substrate, included, the latter brightener is preferably one of the above classes.

Particularly suitable in the agents according to the invention as brighteners which produce a reddish shade are those from the class of the naphthotriazolyl-stilbene and the triazolylcoumarins.

• 2,5-Bis-(benzoxazol-2-yl)-thiophen, 4-(5-Methylbenzoxazol-2-yl)-4'-carbomethoxystilben,
• 1-Methyl-5-methoxynaphthalimid,
• 3-Phenyl-7-(4-phenyl-5-methyl-v-triazol-2-yl)cumarin,
• 3-(4-Chlorpyrazol-1 -yl)-7-(4-phenyl-5-methyl-v-triazol-2-yl)cumarin
• sowie insbesondere
• 3-(2-Phenyl-v-triazol-4-yl)-7-methoxycumarin und
• 4-(Naphtho[1,2-d]triazol-2-yl)-4'-carbäthoxystilben.

Examples of brighteners which produce a reddish shade and which can be used in agents according to the invention include:

• 2,5-bis (benzoxazol-2-yl) thiophene, 4- (5-methylbenzoxazol-2-yl) -4'-carbomethoxystilbene,
• 1-methyl-5-methoxynaphthalimide,
• 3-phenyl-7- (4-phenyl-5-methyl-v-triazol-2-yl) coumarin,
• 3- (4-chloropyrazol-1-yl) -7- (4-phenyl-5-methyl-v-triazol-2-yl) coumarin
• as well as in particular
• 3- (2-phenyl-v-triazol-4-yl) -7-methoxycoumarin and
• 4- (Naphtho [1,2-d] triazol-2-yl) -4'-carbäthoxystilben.

Substrates made of polyester are particularly preferably brightened with the optical brighteners according to the invention, in particular textile materials made of polyester.

If the lightening process is combined with textile treatment or finishing methods, the combined treatment can in many cases advantageously be carried out with the aid of appropriate stable preparations which contain the optically brightening compounds in such a concentration that the desired lightening effect is achieved.

In some cases, the brighteners are brought to full effect by post-treatment. This can be a chemical (e.g. acid treatment), a thermal or a combined chemical / thermal treatment. This is the procedure, for example, when optically brightening a series of fiber substrates, e.g. B. of polyester fibers, with the brightener according to the invention expedient in such a way that these fibers with the aqueous dispersions (optionally also solutions) of the brightener at temperatures below 75 ° C, z. B. at room temperature, impregnated and subjected to a dry heat treatment at temperatures above 100 ° C, it is generally advisable that fiber material previously at a moderately elevated temperature, for. B. to dry at least 60 ° C to about 130 ° C. The heat treatment in the dry state is then advantageously carried out at temperatures between 120 and 225 ° C., for example by heating in a drying chamber, by ironing in the specified temperature interval or by treatment with dry, superheated steam. The drying and dry heat actions can also be carried out immediately one after the other or combined in a single operation.

The amount of the optical brightener to be used according to the invention, based on the material to be optically brightened, can vary within wide limits. Even with very small quantities, in certain cases e.g. B. those of 0.001 percent by weight, a clear and durable effect can be achieved. However, amounts of up to about 0.8 percent by weight and optionally up to about 2 percent by weight can also be used. For most practical purposes, amounts between 0.01 and 0.5 percent by weight are preferred.

Unless otherwise stated, parts in the following examples are always parts by weight and percentages are always percentages by weight.

example 1

versetzt wird, wobei das Reaktionsprodukt sofort kristallin ausfällt.53.6 g of terephthalaldehyde are suspended in 300 ml of absolute ethanol and 144 g of a 30% strength methanolic sodium methylate solution are added at 20 to 25 ° C. with stirring and nitrogen over the course of 15 minutes. An almost clear solution is formed which is 20 to 25 ° C with stirring and nitrogen within 20 minutes with 102 g of the phosphonate of the formula

is added, the reaction product immediately precipitating crystalline.

und 11,3% der Verbindung der Formel

identifizieren läßt.The resulting thick crystalline slurry is then stirred for six hours at 20 to 25 ° C under nitrogen, then suction filtered, washed with about 50 ml of absolute ethanol and dried under vacuum at 50 ° C to constant weight. 60.06 g (about 64.4% of theory) of a light yellow crystalline powder of melting point 144 to 149 ° C. are obtained, which by gas chromatographic analysis is a mixture consisting of 87.8% of the compound of the formula

and 11.3% of the compound of the formula

can be identified.

The phosphonate of formula (14) used as starting material is prepared and in analogy to example 1 of DE-A-1,921,466 purified by distillation (bp _{o, 35:} 136-138 ° C).

werden in 200 ml Dimethylformamid suspendiert und bei 30°C unter Rühren und Stickstoff innerhalb 30 Minuten mit 19,0 g einer 38%igen methanolischen Natriummethylat-Lösung versetzt, wobei die Reaktionstemperatur bis 40°C steigt. Es entsteht zuerst eine fast klare Lösung, aus welcher das Reaktionsprodukt gegen Ende der Zugabe der Natriummethylat-Lösung als dicker kristalliner Brei ausfällt. Das Reaktionsgemisch wird nun bei 30°C unter Stickstoff vier Stunden weitergerührt, dann bei 20°C mit 200 ml Wasser verdünnt und mit etwa 1 ml Eisessig neutralisiert. Das Reaktionsprodukt wird abgenutscht, mit etwa 100 ml Dimethylformamid/Wasser (1 : 1) und dann mit etwa 100 ml Methanol gewaschen und unter Vakuum bei 100° C bis zum konstanten Gewicht getrocknet. Man erhält 28,9 g (etwa 86,9% der Theorie) eines hellgelben kristallinen Pulvers vom Schmelzpunkt 188 bis 233°C, das sich nach gaschromatographischer Analyse als ein Gemisch bestehend aus 91,2% der Verbindung der Formel

und 7,7% der Verbindung der Formel (4) erweist.23.3 g of a mixture of the compounds (16) and (4) obtained as described above and 25.3 g of the phosphonate of the formula

are suspended in 200 ml of dimethylformamide and 19.0 g of a 38% strength methanolic sodium methylate solution are added at 30 ° C. with stirring and nitrogen within 30 minutes, the reaction temperature rising to 40 ° C. First an almost clear solution is formed, from which the reaction product precipitates as a thick crystalline slurry towards the end of the addition of the sodium methylate solution. The reaction mixture is then stirred for a further four hours at 30 ° C. under nitrogen, then diluted with 200 ml of water at 20 ° C. and neutralized with about 1 ml of glacial acetic acid. The reaction product is filtered off, washed with about 100 ml of dimethylformamide / water (1: 1) and then with about 100 ml of methanol and dried under vacuum at 100 ° C to constant weight. 28.9 g (about 86.9% of theory) of a light yellow crystalline powder of melting point 188 to 233 ° C. are obtained, which, according to gas chromatographic analysis, is a mixture consisting of 91.2% of the compound of the formula

and 7.7% of the compound of formula (4).

The phosphonate of the formula (15) used as starting material is prepared according to Example 1 of DE-A-1 921 466.

Example 2

und 7,1% der Verbindung der Formel

erweist.67 g of terephthalaldehyde are suspended in 300 ml of absolute methanol and 180 g of a 30% strength methanolic sodium methylate solution are added at 20 to 25 ° C. with stirring and nitrogen within 15 minutes. An almost clear solution is formed, to which a solution of 126.6 g of the phosphonate of the formula (15) in 100 ml of absolute methanol is added at 20 to 25 ° C. with stirring and nitrogen within 20 minutes, the reaction product immediately precipitating out in crystalline form . The resulting crystalline reaction mixture is further treated as described in Example 1. 106.1 g (about 91.0% of theory) of a light yellow crystalline powder of melting point 198 to 205 ° C. are obtained, which can be analyzed analytically as a mixture consisting of 92.3% of the compound of the formula

and 7.1% of the compound of the formula

turns out.

After three recrystallizations from dioxane and with the aid of activated carbon, 40.6 g of the aldehyde of the formula (17) are obtained in the form of long pale yellow needles with a melting point of 207 to 210 ° C.

23.3 g of a mixture of the compounds (17) and (6) obtained as described above and 25.3 g of the phosphonate of the formula (14) are suspended in 200 ml of dimethylformamide and at 30 ° C. with stirring and nitrogen within 20 minutes 19 g of a 30% methanolic sodium methylate solution are added, the reaction temperature rising to 40 ° C. First an almost clear solution is formed, from which the reaction product precipitates as a thick crystalline slurry towards the end of the addition of the sodium methylate solution. The reaction mixture is further treated as described in Example 1. 30.56 g (about 91.9% of theory) of a light yellow crystalline powder with a melting point of 200 to 230 ° C. are obtained, which can be analyzed as a mixture consisting of 95.7% of the compound of the formula (3) and 3.2 % of the compound of formula (6) proves.

Example 3

in 60 ml absolutem Methanol versetzt wird, wobei das Reaktionsprodukt langsam kristallin ausfällt. Die entstandene kristalline Reaktionsmischung wird nun 24 Stunden bei 20 bis 25° C unter Stickstoff weitergerührt, auf 0°C abgekühlt, dann abgenutscht, mit etwa 50 ml absolutem Äthanol gewaschen und unter Vakuum bei 50° C bis zum konstanten Gewicht getrocknet. Man erhält 32,0 g (etwa 68,7% der Theorie) eines hellgelben kristallinen Pulvers vom Schmelzpunkt 117 bis 192° C, das sich analytisch als ein Gemisch bestehend aus 81,5% der Verbindung der Formel

und 17,2% der Verbindung der Formel

erweist.26.8 g of terephthalaldehyde are suspended in 100 ml of absolute methanol and 72 g of a 30% strength methanolic sodium methylate solution are added at 20 to 25 ° C. with stirring and nitrogen within 15 minutes. An almost clear solution is formed which, at 20 to 25 ° C. with stirring and nitrogen, within 20 minutes with a solution of 50.6 g of the phosphonate of the formula

in 60 ml of absolute methanol, the reaction product slowly precipitating out in crystalline form. The resulting crystalline reaction mixture is then stirred for 24 hours at 20 to 25 ° C under nitrogen, cooled to 0 ° C, then suction filtered, washed with about 50 ml of absolute ethanol and dried under vacuum at 50 ° C to constant weight. 32.0 g (about 68.7% of theory) of a light yellow crystalline powder of melting point 117 to 192 ° C. are obtained, which can be analyzed analytically as a mixture consisting of 81.5% of the compound of the formula

and 17.2% of the compound of the formula

turns out.

After recrystallization from alcohol twice and removal of the alcohol-insoluble compound of the formula (303), 14.5 g of the aldehyde of the formula (302) are obtained in the form of pale yellow needles with a melting point of 117 to 119 ° C.

The phosphonate of the formula (301) used as starting material is prepared according to Example 2 of GB-A-920 988.

und 10,9% der Verbindung der Formel (303) erweist.23.3 g of a mixture of the compounds (302) and (303) obtained as described above and 25.3 g of the phosphonate of the formula (15) are suspended in 200 ml of dimethylformamide and at 30 ° C. with stirring and nitrogen within 15 minutes 19 g of a 30% methanolic sodium methylate solution were added. An almost clear solution is initially formed, from which the reaction product precipitates as a thick crystalline slurry towards the end of the addition of the sodium methylate solution, the reaction temperature rising at 40 ° C. The reaction mixture is then stirred for a further four hours at 30 ° C. under nitrogen, then diluted with 200 ml of water at 0 ° C. and neutralized with about 1 ml of glacial acetic acid. The reaction product is filtered off with suction, washed with about 100 ml of dimethylformamide / water (1: 1) and then with about 80 ml of ethanol and dried under vacuum at 100 ° C. to constant weight. 28.55 g (about 85.9% of theory) of a light yellow crystalline powder with a melting point of 199 to 217 ° C. are obtained, which can be analyzed as a mixture consisting of 88.3% of the compound of the formula

and 10.9% of the compound of formula (303).

Example 4

23.3 g of the mixture of compounds (17) and (6) obtained according to Example 2 and 25.3 g of the phosphonate of the formula (301) are reacted as described in Example 3. 29.4 g (about 88.5% of theory) of a light yellow crystalline powder with a melting point of 204 to 220 ° C. are obtained, which can be analyzed as a mixture consisting of 95.7% of the compound of the formula (304) and 3 , 8% of the compound of formula (6) proves.

Example 5

und 13,8% der Verbindung der Formel (303) erweist.23.3 g of the mixture of compounds (302) and (303) obtained according to Example 3 and 25.3 g of the phosphonate of the formula (14) are reacted in 100 ml of dimethylformamide as described in Example 3. 23.5 g (about 70% of theory) of a pale yellow crystalline powder with a melting point of 174 to 183 ° C. are obtained, which can be analyzed as a mixture consisting of 85.1% of the compound of the formula

and 13.8% of the compound of formula (303).

Example 6

23.3 g of the mixture of the compounds (16) and (4) obtained according to Example 1 and 25.3 g of the phosphonate of the formula (301) are reacted in 100 m) of dimethylformamide as described in Example 3. 24.5 g (about 73.5% of theory) of a pale yellow crystalline powder with a melting point of 176 to 188 ° C. are obtained, which can be analyzed analytically as a mixture consisting of 91.6% of the compound of the formula (501) and 7 , 1% of the compound of formula (4) proves.

Example 7

werden in 80 ml Dimethylformamid wie im Beispiel 3 beschrieben umgesetzt. Man erhält 9,5 g (etwa 87% der Theorie) eines gelben kristallinen Produktes mit einem Schmelzpunkt von 187 bis 205°C, das sich analytisch als ein Gemisch bestehend aus 93,3% der Verbindung der Formel

und 5,6% der Verbindung der Formel (4) erweist.7 g of the mixture of compounds (16) and (4) obtained according to Example 1 and 7.8 g of the phosphonate of the formula

are reacted in 80 ml of dimethylformamide as described in Example 3. 9.5 g (about 87% of theory) of a yellow crystalline product with a melting point of 187 to 205 ° C. are obtained, which can be analyzed analytically as a mixture consisting of 93.3% of the compound of the formula

and 5.6% of the compound of formula (4).

The phosphonate of the formula (701) used as starting material is prepared according to Example 2 of GB-A-929 436.

Example 8

werden in 120 ml Dimethylformamid suspendiert und bei 30° C unter Rühren und Stickstoff innerhalb 15 Minuten mit 22 ml einer äthanolischen 2 M Natriumäthylat-Lösung versetzt. Das Reaktionsgemisch wird wie in Beispiel 3 beschrieben aufgearbeitet. Man erhält 13 g (etwa 86% der Theorie) eines gelben kristallinen Produktes mit einem Schmelzpunkt von 178 bis 181°C, das sich analytisch als ein Gemisch bestehend aus 95,3% der Verbindung der Formel

und 3,9% der Verbindung der Formel (4) erweist.9.3 g of the mixture of compounds (16) and (4) obtained according to Example 1 and 12 g of the phosphonate of the formula

are suspended in 120 ml of dimethylformamide and 22 ml of an ethanolic 2 M sodium ethylate solution are added at 30 ° C. with stirring and nitrogen within 15 minutes. The reaction mixture is worked up as described in Example 3. 13 g (about 86% of theory) of a yellow crystalline product with a melting point of 178 to 181 ° C. are obtained, which can be analyzed analytically as a mixture consisting of 95.3% of the compound of the formula

and 3.9% of the compound of formula (4).

The phosphonate of the formula (801) used as the starting material is prepared analogously to Example 2 of GB-A-929 436 and purified by distillation (bp _0.25 : 181-185 ° C.).

Example 9

und 9,1% der Verbindung der Formel

identifizieren läßt.40 g of terephthalaldehyde are suspended in 100 ml of absolute ethanol and 300 ml of an ethanolic 2 M sodium ethylate solution are added at 20 to 25 ° C. with stirring and nitrogen within 15 minutes. An almost clear solution is formed, to which 90 g of the phosphonate of the formula (801) are added at 20 to 25 ° C. with stirring and nitrogen within 20 minutes, the reaction product immediately precipitating in crystalline form. The resulting thick crystalline slurry is then stirred for 16 hours at room temperature under nitrogen, then suction filtered, washed with about 50 ml of absolute ethanol and dried under vacuum at 50 ° C to constant weight. 64 g (about 76% of theory) of a light yellow crystalline powder having a melting point of 102 to 169 ° C. are obtained, which can be analyzed analytically as a mixture consisting of 89.5% of the compound of the formula

and 9.1% of the compound of the formula

can be identified.

After recrystallizing twice from ethanol and removing the ethanol-insoluble compound of the formula (902), 32 g of the aldehyde of the formula (901) are obtained in the form of long pale yellow needles with a melting point of 103 to 105 ° C.

Example 10

und 5,5% der Verbindung der Formel (303) erweist.8 g of the mixture of the compounds (302) and (303) obtained according to Example 3 and 9 g of the phosphonate of the formula (701) are reacted in 80 ml of dimethylformamide as described in Example 3. 10 g (about 78% of theory) of a pale yellow crystalline powder with a melting point of 228 to 236 ° C. are obtained, which can be analyzed analytically as a mixture consisting of 93.4% of the compound of the formula

and 5.5% of the compound of formula (303).

Example 11

und 6,5% der Verbindung der Formel (303) erweist.9.3 g of the mixture of compounds (302) and (303) and 12 g of the phosphonate of the formula (801) obtained according to Example 3 are suspended in 120 ml of dimethylformamide and at 30 ° C. with stirring and nitrogen with 22 ml within 15 minutes an ethanolic 2 M sodium ethylate solution. The reaction mixture is worked up as described in Example 3. This gives 12.5 g (about 82% of theory) of a yellow crystalline product with a melting point of 194 to 197 ° C., which can be analyzed analytically as a mixture consisting of 92.6% of the compound of the formula

and 6.5% of the compound of formula (303).

Example 12

und 2,6% der Verbindung der Formel (6) erweist.11.7 g of the mixture of compounds (17) and (6) and 13 g of the phosphonate of the formula (701) obtained according to Example 2 are reacted in 100 ml of dimethylformamide as described in Example 3. 16 g (about 87% of theory) of a yellow crystalline powder having a melting point of 219 to 225 ° C. are obtained, which can be analyzed analytically as a mixture consisting of 97.2% of the compound of the formula

and 2.6% of the compound of formula (6).

Example 13

und 3,4% der Verbindung der Formel (6) erweist.9.3 g of the mixture of compounds (17) and (6) and 12 g of the phosphonate of the formula (801) obtained according to Example 2 are suspended in 120 ml of dimethylformamide and at 30 ° C. with stirring and nitrogen with 22 ml within 15 minutes an ethanolic 2 M sodium ethylate solution. The reaction mixture is worked up as described in Example 3. 13.5 g (about 89% of theory) of a yellow crystalline powder having a melting point of 219 to 221 ° C. are obtained, which can be analyzed as a mixture consisting of 95.5% of the compound of the formula

and 3.4% of the compound of formula (6).

Example 14

werden in 60 ml Dimethylformamid suspendiert und bei 30° C unter Rühren und Stickstoff innerhalb 15 Minuten mit 35 ml einer äthanolischen 2,5 M Natriumäthylat-Lösung versetzt. Das Reaktionsgemisch wird wie im Beispiel 3 beschrieben aufgearbeitet. Man erhält 11,5 g (etwa 38% der Theorie) eines gelben kristallinen Pulvers vom Schmelzpunkt 143 bis 169°C, das sich analytisch als ein Gemisch bestehend aus 90,6% der Verbindung der Formel

und 8,3% der Verbindung der Formel (6) erweist.18.6 g of the mixture of compounds (17) and (6) obtained according to Example 2 and 24 g of the phosphonate of the formula

are suspended in 60 ml of dimethylformamide and 35 ml of an ethanolic 2.5 M sodium ethylate solution are added at 30 ° C. with stirring and nitrogen within 15 minutes. The reaction mixture is worked up as described in Example 3. 11.5 g (about 38% of theory) of a yellow crystalline powder of melting point 143 to 169 ° C. are obtained, which can be analyzed analytically as a mixture consisting of 90.6% of the compound of the formula

and 8.3% of the compound of formula (6).

• 55,2 g Natrium werden in 360 ml Toluol vorgelegt und das Toluol auf Rückflußtemperatur erhitzt. Das geschmolzene Natrium wird mit Hilfe eines Vibro-Mischers unter rascher Abkühlung fein gepulvert. Zur erhaltenen toluolischen Natrium-Suspension werden nun bei 60° C unter starker Vibro-Mischung zuerst 5 ml wasserfreies Äthanol und dann 331 g Diäthylphosphit innerhalb einer Stunde zugetropft, wobei das Natrium rasch in Lösung geht. Nach einer weiteren Stunde bei 60°C hat sich das Natrium vollständig gelöst, wobei eine klare Lösung entsteht. Zu dieser Lösung des Natriumsalzes des Phosphorigsäure-Diäthylesters werden nun bei 60°C unter Vibro-Mischung 600 g der Verbindung der Formel
  
  innerhalb einer Stunde zugetropft, wobei Natriumbromid ausfällt. Die erhaltene Suspension wird 20 Stunden bei 60° C unter Vibro-Mischung gehalten, dann auf Raumtemperatur abgekühlt, in Methylenchlorid aufgenommen, mit einer 2 N-Natriumcarbonat-Lösung und dann mit Wasser neutral gewaschen, mit Natriumsulfat getrocknet und unter Vakkuum am Rotationsverdampfer zur Trockne eingeengt. Man erhält 696 g eines gelb-braunen Öls, das nach Destillation 503 g (70% der Theorie) des Phosphonates der Formel (1401) als gelbes Öl (Kp_0,08 : 158-160°C) liefert.

The phosphonate of formula (1401) used as the starting material is prepared as follows:

• 55.2 g of sodium are placed in 360 ml of toluene and the toluene is heated to the reflux temperature. The molten sodium is finely powdered with the help of a vibrator while cooling rapidly. 5 ml of anhydrous ethanol and then 331 g of diethyl phosphite are then added dropwise to the toluene sodium suspension obtained at 60.degree. C. with a strong vibro mixture, the sodium rapidly dissolving. After another hour at 60 ° C, the sodium has completely dissolved, creating a clear solution. 600 g of the compound of the formula are now added to this solution of the sodium salt of the phosphorous acid diethyl ester at 60 ° C. with a vibro mixture
  
  added dropwise within one hour, whereby sodium bromide fails. The suspension obtained is kept for 20 hours at 60 ° C. under a vibro mixture, then cooled to room temperature, taken up in methylene chloride, washed neutral with a 2 N sodium carbonate solution and then with water, dried with sodium sulfate and dried to dryness in vacuo on a rotary evaporator constricted. This gives 696 g of a yellow-brown oil which, after distillation, gives 503 g (70% of theory) of the phosphonate of the formula (1401) as a yellow oil (bp _0.08 : 158-160 ° C.).

The 2-bromomethyl-benzoic acid ethyl ester of formula (1403) is according to J. Chem. Soc. 121, 2202-2215 (1922).

Example 15

und 12,1% der Verbindung der Formel (902) erweist.19.6 g of the mixture of the compounds (901) and (902) obtained according to Example 9 and 21 g of the phosphonate of the formula (1401) are suspended in 60 ml of dimethylformamide and at 30 ° C. with stirring and nitrogen within 15 minutes with 31 ml an ethanolic 2.5 M sodium ethylate solution. The reaction mixture is worked up as described in Example 3. 11 g (about 37% of theory) of a pale yellow crystalline powder of melting point 125 to 250 ° C. are obtained, which can be analyzed analytically as a mixture consisting of 87.5% of the compound of the formula

and 12.1% of the compound of formula (902).

Example 16

werden in 50 ml Dimethylformamid suspendiert und bei 30° C unter Rühren und Stickstoff innerhalb 15 Minuten mit 31 ml einer äthanolischen 2,5 M Natriumäthylat-Lösung versetzt. Das Reaktionsgemisch wird wie im Beispiel 3 beschrieben aufgearbeitet. Man erhält 23 g (etwa 74% der Theorie) eines blaßgelben kristallinen Pulvers vom Schmelzpunkt 183 bis 250°C, das sich analytisch als ein Gemisch bestehend aus 94,7% der Verbindung der Formel

und 5,4% der Verbindung der Formel (902) erweist.19.6 g of the mixture of compounds (901) and (902) obtained according to Example 9 and 21 g of the phosphonate of the formula

are suspended in 50 ml of dimethylformamide and mixed with 31 ml of an ethanolic 2.5 M sodium ethylate solution at 30 ° C. with stirring and nitrogen within 15 minutes. The reaction mixture is worked up as described in Example 3. 23 g (about 74% of theory) of a pale yellow crystalline powder of melting point 183 to 250 ° C. are obtained, which can be analyzed analytically as a mixture consisting of 94.7% of the compound of the formula

and 5.4% of the compound of formula (902).

The phosphonate of the formula (1601) used as the starting material is prepared analogously to Example 2 of GB-A-929 436 and purified by distillation (bp _0.3 : 183-185 ° C.).

Example 17

1 g of the brightener consisting of 91.2% of the compound of formula (3) and 7.7% of the compound of formula (4) is dispersed in 1000 ml of water. 7.5 ml of this dispersion are added to 100 ml of water containing 0.1 g of a fatty alcohol polyglycol ether. To this heated to 60 ° C Brightener dispersion is given a 15 g polyester fabric. The temperature is raised to 120 ° C. in the course of 15 to 20 minutes and left at this temperature for 30 minutes. Then it is cooled to 60 ° C. within 10 to 15 minutes. The fabric is then rinsed in running cold water for 2 minutes and then dried at 60 ° C for 20 minutes.

The fabric treated in this way has a strong lightening effect and good lightfastness.

If, instead of the brightener mentioned, one uses from 95.7% of the compound of the formula (3) and 3.2% of the compound of the formula (6) or one from 88.3% of the compound of the formula (304) and 10.9% of the compound of formula (303), similarly good lightening effects are obtained.

Example 18

Polyester fabric is padded at room temperature with an aqueous dispersion which contains 0.5 g of a brightener consisting of 91.2% of the compound of the formula (3) and 7.7% of the compound of the formula (4) and 1 g of an addition product per liter contains about 8 moles of ethylene oxide to 1 mole of p-tert-octylphenol. The fluid intake is 60 to 70%. The fabric is dried at 100 ° C and then heated to 180 ° C for 15 seconds.

The fabric treated in this way has a strong lightening effect and good lightfastness.

If, instead of the brightener mentioned, one uses from 95.7% of the compound of the formula (3) and 3.2% of the compound of the formula (6) or one from 88.3% of the compound of the formula (304) and 10.9% of the compound of formula (303), similarly good lightening effects are obtained.

Similar brightening effects are achieved by the two methods of Examples 17 and 18, if a two-component brightener consisting of 95.7% of the compound of the formula (304) and 3.8% of the compound of the formula (6); 85.1% of the compound of formula (501) and 13.8% of the compound of formula (303); 91.6% of the compound of formula (501) and 7.1% of the compound of formula (4); 93.3% of the compound of formula (702) and 5.6% of the compound of formula (4); 95.3% of the compound of formula (802) and 3.9% of the compound of formula (4); 93.4% of the compound of formula (1001) and 5.5% of the compound of formula (303); 92.6% of the compound of formula (1101) and 6.5% of the compound of formula (303); 97.2% of the compound of formula (1201) and 2.6% of the compound of formula (6); 95.5% of the compound of formula (1301) and 3.4% of the compound of formula (6); 90.6% of the compound of formula (1402) and 8.3% of the compound of formula (6); 87.5% of the compound of formula (1501) and 12.1% of the compound of formula (902); or 94.7% of the compound of formula (1602) and 5.4% of the compound of formula (902).

Example 19

1 g of the brightener consisting of 91.2% of the compound of formula (3) and 7.7% of the compound of formula (4) is dispersed in 1000 ml of water. 3m) 100 ml of water are added to this dispersion, which contain 0.06 g of an alkyl polyglycol ether. A 3 g heavy polyamide fabric (polyamide 6 or 66) is added to this brightener dispersion heated to 60 ° C. The temperature is raised to 95 to 97 ° C. within 10 to 15 minutes and left at this temperature for 30 minutes. The fabric is then rinsed in running cold water for 2 minutes and then dried at 60 ° C for 20 minutes.

The fabric thus obtained has a strong lightening effect with good light fastness.

If, instead of the brightener mentioned, one uses from 95.7% of the compound of the formula (3) and 3.2% of the compound of the formula (6) or one from 88.3% of the compound of the formula (304) and 10.9% of the compound of formula (303), similarly good lightening effects are obtained.

Example 20

in einem Mischungsverhältnis von 1 : 2 bzw. 2 : 1, sowie 1 g eines Fettalkoholpolyglykoläthers enthält.A bath is produced which contains 0.0125.0.025 or 0.05% by weight, based on the polyester material to be lightened, of a brightener mixture consisting of a brightener composed of 95.7% of the compound of formula (3) per liter of plasticizer. and 3.2% of the compound of formula (6) and a brightener of the formula

in a mixing ratio of 1: 2 or 2: 1, and 1 g of a fatty alcohol polyglycol ether.

At 40 ° C a polyester fabric (»Terylene® Type 540«) in a liquor ratio of 1:20 is placed in the bath, which is in a conventional HT dyeing machine. The mixture is heated to 110, 120 and 130 ° C. over a period of 30 minutes and the bath is kept at the respective temperature for 30 minutes. The mixture is then cooled to 40 ° C. within 15 minutes. The treated fabric is rinsed in flowing, softened water for 30 seconds and then dried.

The treated fabric pieces show strong, brilliant lightening effects with a pleasing nuance. The greenish-bluish shade obtained from the compounds (3) and (6) when lightening with the brightener is clearly shifted into the reddish area.

Example 21

Polyester fabric ("Terylene type 540") is padded at room temperature with an aqueous dispersion which contains 0.125, 0.25, 0.5 or 1 g of a brightener mixture, consisting of a brightener made from 95.7% of the compound of the formula ( 3) and 3.2% of the compound of formula (6) and a brightener of formula (2001) in a mixing ratio of 1: 2 or 2: 1, and 1 ml of an alkylphenol polyglycol ether. The fleet intake is 80%. The fabric is dried for 10 minutes at 80 ° C and then heat set for 30 seconds at 180 °, 200 or 220 ° C.

The treated fabric pieces show strong, brilliant lightening effects with a pleasing nuance. The greenish-bluish shade obtained from the compounds (3) and (6) when lightening with the brightener is clearly shifted into the reddish area.

Example 22

oder

ein, so erhält man auf den behandelten Gewebestücken ähnlich gute Effekte, wie sie in den Beispielen 20 und 21 beschrieben sind.If example 20 or 21 are repeated, but instead of the brightener of the formula (2001), the same amount of one of the brighteners of the formula is used

or

a, similarly good effects are obtained on the treated tissue pieces as described in Examples 20 and 21.

The brightener from compounds (3) and (6) can also be replaced by any other two-component brightener obtainable according to Examples 1, 3-8 and 10-16.

Claims (21)

1. A fluorescent brightener comprising a mixture of bis-styrylbenzene compounds and consisting of 51-99% by weight of an unsymmetrically substituted compound of the formula

wherein R and R, are identical or different and, if R and R, are identical, R, must occupy in the phenyl ring to which it is attached a position which differs from the position occupied by R in its phenyl ring, and wherein R and R, independently of each other are CN or an unsubstituted or substituted carboxylic acid ester group, and 49-1 % by weight of a symmetrically substituted compound of the formula

wherein R is as defined above and each R is attached to an identical position in its phenyl ring.

2. A fluorescent brightener according to claim 1, wherein R₁ in the unsymmetrically substituted compound of the formula (1) occupies a different position in the phenyl ring to which it is attached than the position occupied by R in its phenyl ring.

3. A fluorescent brightener according to claim 1 or 2, wherein, in the two individual components, R and R₁ independently of each other are CN or a group of the formula -COOY, in which Y is alkyl, haloalkyl, aralkyl, carbalkoxyalkyl, cyanoalkyl, hydroxyalkyl, aminoalkyl, alkylaminoalkyl or dialkylaminoalkyl, and each of the abovementioned alkyl groups and alkyl moieties in composite groups contains 1 to 6 carbon atoms; or Y is alkenyl of 3 to 6 carbon atoms, cycloalkyl of 5 to 6 carbon atoms, propargyl, tetrahydrofurfuryl or a group of the formula

in which X is hydrogen or methyl and n is a value from 1 to 4 and the alkyl group contains 1 to 6 carbon atoms.

4. A fluorescent brightener according to claim 3, wherein R and R₁, each independently of the other, are -CN or -COOY', in which Y' is alkyl of 1 to 4 carbon atoms, but R and R' are preferably each -CN.

5. A fluorescent brightener according to claim 4, consisting of 51-99% by weight of the compound of the formula

and 49-1 % by weight of the compound of the formula

or of the formula

6. A fluorescent brightener according to any one of claims 1 to 5, consisting of 70-99% by weight, preferably 90-99% by weight, of the unsymmetrically substituted compound, especially of the formula (1) or (3), and 30 to 1% by weight, preferably 20 to 1% by weight and most 10 to 1% by weight, of the symmetrically substituted compound, especially of the formula (2), (4) or (6).

7. A process for the preparation of a fluorescent brightener as defined in claim 1 or 2, which comprises reacting terephthalaldehyde with a compound of the formula

in the presence of an alkaline condensing agent, to give a mixture of the compounds of the formula

and

and then further reacting this mixture with a compound of the formula

in the presence of an alkaline condensing agent, to give the fluorescent brightener defined in claim 1 or 2, wherein R and R₁ are as defined in claim 1 or 2 and must satisfy the conditions laid down in these claims with regard to their positions in the phenyl rings, and X and Y are identical or different and independently of each other are hydrogen or a radical of the formula

the ratio of terephthalaldehyde to the compound of formula (7) being so chosen that the ratio of symmetrical to unsymmetrical component in the final product is within the range indicated in claim 1.

8. A process according to claim 7, wherein the reaction of terephthalaldehyde with a compound of the formula

is carried out in a solvent or solvent mixture in which the resulting monoaldehyde is sparingly soluble and crystallises out.

9. A process according to either claims 7 or 8, wherein the reaction of terephthalaldehyde with a compound of the formula

is carried out in the presence of an alkali metal alcoholate, in the temperature range from 0° to 50° C, preferably from 20° to 30° C.

10. A process according to either claims 7 or 8, wherein the monoaldehyde-containing mixture obtained in the first stage is further reacted without isolation.

11. A process according to claim 7, wherein the reaction of the mixture obtained in the first stage with a compound of the formula

is carried out in the presence of an alkali metal alcoholate, in the temperature range from 20° to 100° C, preferably from 30° to 50° C.

12. A composition for brightening high molecular weight organic materials, which contains a fluorescent brightener as defined in claims 1 to 10.

13. A composition according to claim 12, which additionally contains conventional formulation assistants.

14. A composition according to claim 12, which, in addition to containing a fluorescent brightener as defined in claims 1 to 6, which gives a greenish to bluish hue on the treated substrate, also contains a fluorescent brightener which gives a reddish hue on the treated substrate.

15. A composition according to claim 14, which additionally contains a fluorescent brightener of the class of the naphthalimides, bis-benzoxazolylethylenes, bis-benzoxazolylthiophenes, stilbenylbenzox- azoles, naphthotriazolylstilbenes or triazolylcoumarins.

16. A composition according to claim 14, which contains, as fluorescent brightener 5-90% by weight, preferably 30-70% by weight, of a fluorescent brightener as defined in claims 1 to 6, which gives a greenish to bluish hue on the treated substrate, and 95-10% by weight, preferably 70-30% by weight, of a fluorescent brightener which gives a reddish hue on the treated substrate.

17. A composition according to claim 16, which contains a fluorescent brightener comprising the compounds (3) and (4) or (3) and (6) and, in addition, a fluorescent brightener of the class of the naphthotriazolylstilbenes or of the triazolylcoumarins.

18. A process for brightening natural, regenerated man-made or synthetic high molecular weight organic substrates, e. g. polyester, preferably textile fibres, e. g. polyester fibres, which comprises incorporating into said substrates or applying thereto, preferably to textile fibres, a fluorescent brightener as defined in claims 1 to 6, or a composition according to claims 12 to 17.

19. The use of a fluorescent brightener defined in claims 1to 6 for brightening natural, regenerated man-made or synthetic high molecular weight organic material, especially made of polyester, in particular of polyester fibres.

20. A process for the preparation of a stilbenealdehyde of the formula

in admixture with a bis-styrylbenzene of the formula

in which R₂' is a cyano or a carboxylic acid ester group, especially a carboxylic acid ester group of the formula -COOY, in which Y is alkyl, haloalkyl, aralkyl, carbalkoxyalkyl, cyanoalkyl, hydroxyalkyl, aminoalkyl, alkylaminoalkyl or dialkylaminoalkyl, and each of the abovementioned alkyl groups and alkyl moieties in composite groups contains 1 to 6 carbon atoms; or alkenyl of 3 to 6 carbon atoms, cycloalkyl of 5 or 6 carbon atoms, propargyl, tetrahydrofurfuryl or a group of the formula

in which X is hydrogen or methyl and n is a value from 1 to 4 and the alkyl group contains 1 to 6 carbon atoms, which comprises reacting terephthalaldehyde with a compound of the formula

in which X' is a radical of the formula

in a solvent in which the stilbene aldehyde is sparingly soluble and in the presence of an alkaline condensing agent.

21. A process according to claim 20, which comprises isolating the stilbene aldehyde from the mixture by recrystallisation, which is repeated if necessary, or by chromatography.