Title of Invention	AMPHOTERIC BIS-TRIAZINYLAMINOSTILBENE FLUORESCENT WHITENING AGENTS
Abstract	The present invention provides novel bis-triazinylaminostilbene amphoteric fluorescent whitening agents, comprising both individual components and mixtures thereof, a process for their preparation, intermediates useful for their preparation and use of the fluorescent whitening agents for the fluorescent whitening of paper.

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Amphoteric Fluorescent Whitening Agents The present invention relates to amphoteric bis-triazinylaminostilbene fluorescent whitening agents (FWA's,, a process for their preparation and the use thereof for fluorescent whitening of synthetic or natural organic materials, in particular, paper. The most commonly used types of fluorescent whitening agent for the fluorescent whitening of paper are those belonging to the class of di-, tetra- or hexasulphonic acid derivatives of bis-triazinylaminostilbenes, which are anionic in nature. Modern paper-making techniques, however, generally employ cationic polymers as assistants, for example, as retention agents or dewatering aids, in particular, during the production of recycling papers, which, most probably contain residual amounts of anionic FWA's. The presence of cationic polymers, however, results in quenching of the fluorescence of anionic FWA's, which is clearly disadvantageous. Consequently, there is a need for a type of FWA, which is not quenched by such polymers and, in addition, is combfnable with anionic FWA's. Surprisingly, it has now been found that certain novel amphoteric FWA's are neither detrimentally affected by the presence of cationic polymers nor by the presence of residual amounts of anionic FWA's and also exhibit excellent whitening properties when applied to paper. Accordingly, in a first aspect, the present invention provides novel amphoteric fluorescent whitening agents, which comprise a mixture of compounds of the formulae wherein D represents -NR5R6 and E represents -Xt-YrNRrRe, whereby X and Xi each, independently of each other, represent -O- or -NH-, Y and Y1 each, independently of each other, represent a straight-chain C2-C8alkylene or branched C3-C8alkylene chain, which may be interrupted by one or two nitrogen, oxygen or sulphur atoms or represent a 5- or 6-membered cycloaliphatic ring, preferably cyclohexyl, Ri. R2. R5 and R6 each independently of each other, represent hydrogen, C1-8alkyl, C2-C4hydroxyalkyl, C1-C4alkoxy,aIkyl, phenyl, which is unsubstituted or substituted by halogen, ,alkoxy, ,alkyl or sulphonamido, or R, and R2 and /or R5 and R6, together with the nitrogen atom to which they are attached, complete a morpholino-, piperidino- or pyrrolidino-ring, R3. R4. R, and R8, each independently of each other, represent hydrogen, C1-4alkyl, C2-C4hydroxyalkyl or R3 and R4 and/or R7 and R8, together with the nitrogen atom to which they are attached, complete a morpholino-, piperidino- or pyrrolidino-ring and M represents hydrogen, an alkaline or alkaline earth metal, ammonium or alkyl ammonium. Amphoteric compounds of formula (1a, - (1c, may exist either in the form of an internal or external salt. Thus, for example, in the case in which M in the above formulae represents hydrogen, compounds (1a, - (1c, may exist as an equilibrium mixture of a neutral molecule and of a zwitterion, wherein M designates a negative charge in the form of S03 whilst the proton resides on the amine residues in the form of ammonium salts -N+ HR3R4 and -N HR7Re. Consequently, in order for the compounds of formulae (1 a, - (1 c, to be truly amphoteric in character, it is necessary for the total number of acidic groups and of basic amino groups present in the molecule to be equal. Since the diaminostilbene disulphonic acid moiety already contains two sulphonic acid groups, it is preferable that no further acidic groups are present in the molecules (1a, - (1c, and, furthermore, that they are substituted with two amino groupswhich are of sufficiently high basicity to be capable of forming zwitterions i.e. in addition to amino groups attached directly to a triazine ring. In one preferred aspect, the invention relates to a fluorescent whitening agent, which comprises a mixture of compounds of the formulae in which X, Y, R1p R2l R3, R4, R5, R6 and M are as previously defined and, more especially, mixtures of compounds ,1d,, ,1e, and ,If,, in which Y is a straight chain C2-C6alkylene or branched C3-C6alkylene residue which may be interrupted by 1 or 2 oxygen atoms, Ri. R2, Rsand R6 each independently of each other, represent hydrogen, C1-4alkyl, C2-C4hydroxyalkyl, phenyl, which is unsubstituted or substituted by methoxy, ethoxy or -S02NH2 or RT and R2, and/or R5 and R6, together with the nitrogen atom to which they are attached, complete a morpholino ring, R3 and R4 both represent CrC4alkyl, C2-C4hydroxyalkyl or, together with the nitrogen atom to which they are attached, complete a morpholino ring, M represents hydrogen, lithium, potassium or sodium and X is as defined previously. Most preferred mixtures of compounds ,1d, - ,1f, are those in which X represents -O- or -NH-, Y represents a straight chain C2-C4alkylene or branched C3-C4alkylene residue Ri and R5 both represent hydrogen, C1-4alkylf C2-C4hydroxyalkyl or phenyl, R2 and R6 both represent hydrogen or C2-C4hydroxyaIkyl, R3 and R4 both represent C1-4alkyl, C2-C4hydroxyalkyl or, together with the nitrogen which they are attached, complete a morpholino ring and M represents hydrogen or sodium. In a second preferred aspect, the invention relates to a fluorescent whitening agent, which comprises a mixture of compounds of the formulae in which Xt X1t Y, Y1, R1, R2, R3, R4, R7, R6 and M are as defined previously, and, more especially, mixtures of compounds ,1d,, ,1g, and ,1h, in which X and X1 both represent -NH-, Y and Y1 each, independently of each other, represent a straight chain C2-C6alkylene or branched C3-C6alkylene residue which may be interrupted by 1 or 2 or oxygen atoms, Ri and R2l each independently of each other, represent hydrogen, C1-4alkyl, C2-C4hydroxyalkyl, phenyl, which is unsubstituted or substituted by methoxy, ethoxy or -S02NH2or R1 and R2, together with the nitrogen atom to which they are attached, complete a morpholino ring, R3, R4. R7 and Ra, each independently of each other, represent hydrogen, C1-C4alkylf C2-C4hydroxyalkyl or R3 and R4 and/or R7 and R8, together with the nitrogen atom to which they are attached, complete a morpholino ring and M represents hydrogen, lithium, potassium or sodium. Most preferred mixtures of compounds ,1d,, ,1g, and ,1h, are those in which X and X1 both represent -NH-, Y and Y1 each, independently of each other, represent a straight chain C2-C4alkylene or branched C3-C4alkylene residue, Ri represents hydrogen, C1-4alkyl, C2-C4hydroxyalkyl or phenyl, R2 represents hydrogen or C2-C4hydroxyalkyl or RT and R2, together with the nitrogen atom to which they are attached, complete a morpholino ring, R, R4, R7 and R8t each independently of each other, represent hydrogen, C1-C4alkyl C2- C4hydroxyalkyl or R3 and R4 and/or R7 and R8, together with the nitrogen atom to which they are attached, complete a morpholino ring and M represents hydrogen or sodium. In a third aspect, the present invention provides novel amphoteric fluorescent whitening agents of the formula" in which X, Y, Y1, R1. R2, R3l R4, R5, Re. R7, R8 and M are as defined previously, whilst those compounds of formula ,2, are preferred, in which X1 represents oxygen, Y and Y1 each, independently of each other, represent a straight chain C2-C6alkylene or branched C3-C6alkylene residue which may be interrupted by 1 or 2 oxygen atoms, R1, R2, R5 and R6 each independently of each other, represent hydrogen, C1-4alkyl, C2-C4hydroxyalkyl, phenyl, which is unsubstituted or substituted by methoxy, ethoxy or -S02NH2 or RT and R2 and/or R5 and R6l together with the nitrogen atom to which they are attached, complete a morpholino ring, R31 R4, R7 and R8| each independently of each other, represent hydrogen, C1-4alkyl, C2-C4hydroxyalkyl or R3 and R4 and/or R7 and R8, together with the nitrogen atom to which they are attached, complete a morpholino ring and M represents hydrogen, lithium, potassium or sodium. Most preferred compounds of formula ,2, are those in which Xt represents oxygen, Y and Y, both represent a straight chain C2-C4alkylene or branched C3-C4alkylene residue, Ri and R5 are each identical and represent hydrogen, C1-4alkyl, C2-C4hydroxyalkyl or phenyl, R2 and R6 are each identical and represent hydrogen, C1-4alkyl, C2-C4hydroxyalkyl or Ri and R2 and R5 and R6, together with the nitrogen atom to which they are attached, complete a morpholino ring, R3. R4, R7 and R8 are all identical and represent hydrogen or C1-4alkyl and M represents hydrogen or sodium, especially hydrogen. In a fourth aspect, the invention relates to a fluorescent whitening agent, which is a compound of the formula in which R9 and R10t each independently of each other, represent hydrogen or C2-C4hydroxyalkyi and Y, Yi, R1R2l R3, R4, R5l R6, and M are as defined previously, with the proviso that when Y and Yt both represent -CH2CH2CHr, Ri and R5 are both phenyl and R2 and R6 are both hydrogen, R3, R^ R9 and R10 are not all -CH2CH2OH, whereby, preferred compounds of formula ,3, are those in which Y and Y, each, independently of each other, represent a straight chain C2-C6alkylene or branched C3-C6alkylene residue which may be interrupted by 1 or 2 oxygen atoms or one nitrogen atom or represent a cyclohexyl moiety, R1R2, R5 and R6 each independently of each other, represent hydrogen, C1-8alkyl, C2-C4hydroxyalkyl, phenyl, which is unsubstituted or substituted by methoxy, ethoxy or -S02NH2 or Ri and R2 and/or R5 and R6, together with the nitrogen atom to which they are attached, complete a morpholino ring, R3, and R4 each independently of each other, represent hydrogen, C1-C4alkyl, C2- C4hydroxyalkyl or R3 and R4f together with the nitrogen atom to which they are attached, complete a morpholino ring and M represents hydrogen, lithium, potassium or sodium. Most preferred compounds of formula ,3, are those in which, Y and Yt both represent a straight chain C2-C6alkylene, which may be interrupted by 1 or 2 oxygen atoms or one nitrogen atom, or represent a cyclohexyl moiety, R1 and R5 are each identical and represent hydrogen, C1-8alkyl, C2-C4hydroxyalkyl, ethoxyphenyl or phenyl, R2 and R6 are each identical and represent hydrogen, C1-4alkyl, C2-C4hydroxyalkyl or each R1 and R2 and Rs and R6, together with the nitrogen atom to which they are attached, complete a morpholino ring, R3 and R9 are identical and each represents hydrogen or hydroxyethyl, R4 and R,0 are identical and each represents hydrogen or hydroxyethyl and M represents hydrogen or sodium, especially hydrogen. Within the scope of the definitions of the substituents, C1-8alkyl groups are, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl or t-butyl, n-pentyl, ethyl propyl, dimethyl propyl, methyl butyl, n-hexyl, dimethyl butyl, methyl pentyl, ethyl butyl, n-heptyl, methyl hexyl, dimethyl pentyl, ethyl pentyl, trimethyl butyl, n-octyl, methyl heptyl, dimethyl or ethyl hexyl or a trimethyl pentyl, whilst C1-4alkoxy groups are, for example, methoxy, ethoxy, n-propoxy, isopropoxy, n-, sec-, iso- or t-butoxy. A C2-C8alkylene chain, in the definitions of Y and Y1t may, for example be an ethylene, n-propylene, methyl ethylene, 1- or 2-methylpropylene, n-butylene, ethylethylene, n-pentylene, ethyl propylene, dimethyl propylene, methyl butylene, n-hexylene, dimethyl butylene, methyl pentylene, ethyl butylene, n-heptylene, methyl hexylene, dimethyl pentylene, ethyl pentylene, trimethyl butylene, n-octylene, methyl heptylene, dimethyl or ethyl hexylene or a trimethyl pentylene chain. Where the C2-C8alkylene chain is interrupted by heteroatoms, these may be sulphur or, especially, oxygen, whilst C2-C4 hydroxyalkyl may be hydroxyethyl, hydroxy-n- or isopropyl or hydroxybutyl. Further, within the scope of the definitions, halogen is iodine, bromine, fluorine or, especially, chlorine, whilst sulphonamido may be-S02NHC1-4alkyl, -S02N,C1-C4alkyl,2 or, especially, S02NH2. Where M represents an alkaline or alkaline earth metal, this may be lithium, potassium, sodium, calcium or magnesium, whilst alkyl ammonium may be ammonium which is mono-, di-, tri- or tetra substituted by C1-4alkyl or C2-C4hydroxyalkyl or a mixture thereof. Preferably, M represents hydrogen or sodium. The mixture of compounds of formulae ,1 a,, ,1 b, and ,1 c, of the invention may be prepared by reacting, under known reaction conditions, cyanuric chloride, successively, in any desired sequence, with each of 4,4,-diaminostilbene-2,2'- disulphonic acid, amino compounds of formulae R1R2NH and R5ReNH or mixtures thereof and compounds of formulae R3R4NYXH and R7R8NY1H or mixtures thereof, whereby X, X1f Y, Y1f R1f R2, R3, R4, R5l R6, R7 and R8 are as previously defined. Depending on the amounts and proportions of the amines R1R2NH and R5R6NH and of the compounds of formulae R3R4NYXH and R7R8NY1H and whether they are added sequentially or simultaneously as a mixture, the proportions of the compounds ,1a,, ,1b, and ,1c, can be varied considerably. Thus, the present invention relates to a fluorescent whitening agent which comprises a mixture of the compounds ,1a,, ,1b, and ,1c, wherein each of the components are present in a molar ratio of between 5 and 80%, preferably they are present in the approximate molar ratios of 5-45% of the compound of formula ,1a,, 15-60% of the compound of formula ,1 b, and 5-45% of the compound of formula ,1c,. More preferably, the compounds ,1a,, ,1b, and ,1c, are present in the approximate molar ratios of 20-50% of the compound of formula ,1a,, 25-50% of the compound of formula ,1b, and 5-35% of the compound of formula ,1c,. Naturally, such mixtures may also be obtained by mechanical mixing of the individually prepared components. Similarly, the compound of formula ,2, may be prepared by reacting, under known reaction conditions, cyanuric chloride, successively, in any desired sequence, with each of 4,4'-diaminostilbene-2,2'- disulphonic acid, an amino compound of formula R1R2NH, an amino compound of formula R5R6NH, a hydroxy compound of formula R3R4NYOH and a compound of formula R7R8NY1H, Xt Y, Ytl R1t R2, R3. R4, R5, Re, R, and R8 being as previously defined. In an analogous manner, the compound of formula ,3, may be by reacting, under known reaction conditions, cyanuric chloride, successively, in any desired sequence, with each of 4,4,-diaminostilbene-2,2'- disulphonic acid, an amino compound of formula R1R2NH, an amino compound of formula R5R6NH, an amino compound of formula R3R4NYNH2 and a compound of formula R7R8NY1H, Y, Yi, R1, R2, R3, R4, R5, Re, R9 and R10 being as previously defined. In certain cases, it may be advantageous to isolate the intermediate dichlorotriazinylamino derivatives of '-diaminostilbene,,- disulphonic acid, either as pure asymmetric compounds or as their mixtures, which are subsequently reacted further to yield either mixtures of compounds of formulae ,1a,t ,1b, and ,1c,, compounds of formula ,2, or compounds of formula ,3,. Since a number of these intermediate dichloro derivatives are novel, a further aspect of the invention is a compound of formula in which Rn and R12l each independently of each other, represent hydrogen, C1-4alkyl, C2-C4hydroxyaIkylf C1-C4alkoxyC1-C4all are attached, complete a morpholino-, piperidino- or pyrrolidino-ring, R13 represents phenyl, which is unsubstituted or substituted by halogen, C1-4alkoxy, C1-4alkyl or sulphonamido and M represents hydrogen, an alkaline or alkaline earth metal, ammonium or alkyl ammonium. Preferably, R^ and R12l each independently of each other, represent hydrogen, C1-4a!kyl, C2-C4hydroxyalkyl, especially, both representing C1-C3hyroxyalkyl or, together with the nitrogen atom to which they are attached, complete a morpholino-ring, whilst R13 represents phenyl, which is unsubstituted or substituted by methoxy, ethoxy or -S02NH2, especially, unsubstituted, sulphonamido- or ethoxy-substituted phenyl and M represents hydrogen, lithium, potassium or sodium, especially, hydrogen or sodium. In analogy to the previously described processes, compounds of formula ,4a, or a mixture of compounds of formulae ,4a,, ,4b, and ,4c, may be prepared by reacting, under known reaction conditions, cyanuric chloride, successively, in any desired sequence, with each of 4,4'-diaminostilbene-2,2'- disulphonic acid, an amino compound of formula R11R12 NH and an amino compound of formula Ri3NH2 or with a mixture of amino compounds R11R12NH and R13NH2, R11f R12 and R13 being as previously defined. As previously mentioned, intermediate compounds of formula ,4a, are useful for the preparation of those compounds of formula ,2,, wherefn, R, and R2 each independently of each other, represent hydrogen, C1-C4alkyl, C2-C4hydroxyalkyl, C1-4alkoxyC1-4alkyl or, together with the nitrogen atom to which they are attached, complete a morpholino-, piperidino- or pyrroiidino-ring, R5 represents phenyl, which is unsubstituted or substituted by halogen, C1-4alkoxy, C1-C4alkyl or sulphonamido, R6 represents hydrogen and Xi, Y, Yi, R3| R^ R7, R8 and M are as defined previously and also are useful for the preparation of those compounds of formula ,3,, in which, in formula ,3,, Ri and R2 each independently of each other, represent hydrogen, C1-4alkyl, C2-C4hydroxyalkyl, C1-4aIkoxyC1-4alkyl or, together with the nitrogen atom to which they are attached, complete a morpholino-, piperidino- or pyrrolidino-ring, Rs represents phenyl, which is unsubstituted or substituted by halogen, C1-4alkoxy, C1-4alkyl or sulphonamido, R6 represents hydrogen and Y, Yi, R3, R4f R9, R10, and M are as previously defined. Furthermore, the mixtures of compounds of formulae ,4a,, ,4b, and ,4c, are useful for the preparation of those mixtures of compounds of formulae ,1a,, ,1b, and ,1c,, in which, in formulae ,1a,, ,1b, and ,1c,, Rt and R2 each independently of each other, represent hydrogen, C1-4alkyl, C2-C4hydroxyalkyl, C1-4lkoxyC1-4alkyl or, together with the nitrogen atom to which they are attached, complete a morpholino-, piperidino- or pyrrolidino-ring, R5 represents phenyl, which is unsubstituted or substituted by halogen, C1-4alkoxy, C1-4a!kyI or sulphonamiclo, R6 represents hydrogen and X, Xt, Y, Y1, R3, FU, R7l R8 and M are as defined previously. One further aspect of the preparation of certain compounds and compound mixtures described above is also of importance. In the case in which X or X1 represents oxygen and at least one of the substituents R3, R4, R7 and R8 represents hydrogen, it may be necessary to introduce a protective group such as -COAIkyl onto the nitrogen atom in order to ensure reaction occurring in the desired direction, the protective group being subsequently removed by conventional methods. A further synthetic variation, which may be advantageous for the preparation of asymmetric derivatives, is to replace the 4,4,-diaminostilbene-2,2'- disulphonic acid by 4-amino-4'-nitrostilbene-2,2'- disulphonic acid and, after carrying out the desired condensation reactions, reducing the nitro group to an amino group, whereby further desired condensation reactions may subsequently be performed. All starting materials are known compounds, which are readily available or may be prepared by known methods. A further aspect of the invention is a composition for whitening of paper, which contains water, a fluorescent whitening agent which comprises a mixture of compounds of the formulae ,1a,, ,1b, and ,1c,, a fluorescent whitening agent of formula ,2, or a fluorescent whitening agent of the formula Y, Yi, Rtl R2l R3, FU, R5, R6. and M are as defined previously, and, optionally, auxiliaries. Such compositions may comprise not only mixture of compounds of the formulae ,1a,, ,1b, and ,1c,, compounds of formula ,2, and compounds of formula ,5, alone, but also mixtures of the individual component mixtures and components with one another More specifically, such brightener compositions contain water and, in each case based on the weight of the formulation, from 3 to 25% by weight, preferably from 5 to 15% by weight of the above defined fluorescent whitening agent mixture and also 0 to 60%, preferably 5 to 50% by weight, of auxiliaries. Suitable auxiliaries include, for example, anionic or non-ionic dispersants from the class of ethylene oxide adducts with fatty alcohols, higher fatty acids or alkyl phenols or ethylenediamine ethylene oxide-propylene oxide adducts, copolymers of N-vinylpyrrolidone with 3-vinylpropionic acid, polyethylene glycols, water retention aids, such as ethylene glycol, glycerol or sorbitol, or biocides. Since most of the mixtures of compounds of formulae ,1a,, ,1b, and ,1c,, the compounds of formula ,2, and the compounds of formula ,5, are excellent fluorescent whitening agents for substrates such as paper, the present invention further provides a method for the fluorescent whitening of paper comprising contacting the substrate with a fluorescent whitening agent which comprises a mixture of compounds of formulae ,1a,, ,1b, and ,1 c,, a compound of formula ,2, and/or a compound of formula ,5,. When used for the fluorescent whitening of paper, the mixture of compounds of formulae ,1a,, ,1b, and ,1c,, the compound of formula ,2, and/or the compound of formula ,5,, according to the present invention, may be applied to the paper substrate in the pulp mass, in the form of a paper coating composition, or directly in the size press or metering press. In one preferred aspect, the present invention provides a method for the fluorescent whitening of a paper surface, comprising contacting the paper surface with a coating composition comprising a white pigment; a binder dispersion; optionally a water-soluble co-binder; and sufficient of a fluorescent whitening agent, according to the present invention, to ensure that the treated paper contains 0.01 to 1 % by weight, based on the white pigment, of a fluorescent whitening agent of the invention. As the white pigment component of the paper coating composition used according to the method of the present invention, there are preferred inorganic pigments, e.g., aluminium or magnesium silicates, such as China clay and kaolin and, further, barium sulfate, satin white, titanium dioxide, calcium carbonate ,chalk, or talcum; as well as white organic pigments. The paper coating compositions used according to the method of the present invention may contain, as binder, inter alia, plastics dispersions based on copolymers of butadiene/styrene, acrylonitrile/butadiene/styrene, acrylic acid esters, acrylic acid esters/styrene/acrylonitrile, ethylene/vinyl chloride and ethylene/vinyl acetate; or homopolymers, such as polyvinyl chloride, polyvinylidene chloride, polyethylene and polyvinyl acetate or polyurethanes. A preferred binder consists of styrene/butyl acrylate or styrene/butadiene/ acrylic acid copolymers or styrene/butadiene rubbers. Other polymer latices are described, for example, in U.S.Patent Specifications 3,265,654, 3,657,174, 3,547,899 and 3,240,740. The optional water-soluble protective colloid may be, e.g., soya protein, casein, carboxymethylcellulose, natural or modified starch, chitosan or a derivative thereof or, especially, polyvinyl alcohol. The preferred polyvinyl alcohol protective colloid component may have a wide range of saponification levels and molecular weights; e.g. a saponification level ranging from 40 to 100; and an average molecular weight ranging from 10,000 to 100,000. Recipes for coating compositions for paper are described, for example, in J.P. Casey "Pulp and Paper"; Chemistry and Chemical Technology, 2nd edition, Volume III, pagesl 684-1649 and in "Pulp and Paper Manufacture", 2nd and 5th edition, Volume II, page497 ,McGraw-Hill,. The paper coating compositions used according to the method of the present invention preferably contain 10 to 70% by weight of a white pigment. The binder is preferably used in an amount, which is sufficient to make the dry content of polymeric compound up to 1 to 30% by weight, preferably 5 to 25% by weight, of the white pigment. The amount of fluorescent brightener preparation used according to the invention is calculated so that the fluorescent brightener is preferably present in amounts of 0.01 to 1% by weight, more preferably 0.05 to 1% by weight, and especially 0.05 to 0.6% by weight, based on the white pigment. The paper coating composition used in the method according to the invention can be prepared by mixing the components in any desired sequence at temperatures from 10 to 100°C, preferably 20 to 80°C. The components here also include the customary auxiliaries, which can be added to regulate the rheological properties, such as viscosity or water retention capacity, of the coating compositions. Such auxiliaries are, for example, natural binders, such as starch, casein, protein or - gelatin, cellulose ethers, such as carboxyalkylcellulose or hydroxyalkylcellulose, alginic acid, alginates, polyethylene oxide or polyethylene oxide alkyl ethers, copolymers of ethylene oxide and propylene oxide, polyvinyl alcohol, water-soluble condensation products of formaldehyde with urea or-melamine, polyphosphates or polyacrylic acid salts. The coating composition used according to the method of the present invention is preferably used to produce coated printed or writing paper, or special papers such as ink-jet or photographic papers, or cardboard. The coating composition used according to the method of the invention can be applied to the substrate by any conventional process, for example with an air blade, a coating blade, a roller, a doctor blade or a rod, or in the size press, after which the coatings are dried at paper surface temperatures in the range from 70 to 200°C, preferably 90 to 130°C, to a residual moisture content of 3-8%, for example with infra-red driers and/or hot-air driers. Comparably high degrees of whiteness are thus achieved even at low drying temperatures. By the use of the method according to the invention, the coatings obtained are distinguished by optimum distribution of the dispersion fluorescent brightener over the entire surface and by an increase in the level of whiteness thereby achieved, by a high fastness to light and to elevated temperature ,e.g. stability for 24 hours at 60-100°C., and excellent bleed-fastness to water. In a second preferred aspect, the present invention provides a method for the fluorescent whitening of a paper surface comprising contacting the paper in the size press with an aqueous solution containing a size, optionally an inorganic or organic pigment and 0.1 to 20g/l of a fluorescent whitening agent of the invention. Preferably, the size is starch, a starch derivative or a synthetic sizing agent, especially a water-soluble copolymer. In a third preferred aspect, the invention provides a method for the fluorescent whitening of paper during paper formation, whereby the FWA is added directly to the pulp mass. In this case, the FWA may be in the form of a solution, a dispersion or as a powder, whereby the FWA's of the invention are especially valuable in that their effect is not inhibited by the presence of cationic polymers, fixing agents, wet-strengthening agents or de-inking auxiliaries, which are similarly added to the pulp mass prior to paper formation. Examples of such auxiliaries may include dicyandiamide condensation products, polyvinyl amines, polyethylene imines, cationic starches, poly-DADMAC ,diallyl dimethyl ammonium chloride,, polyamide amines and polyepoxides. In a final aspect, the invention relates to paper, which has been treated with a fluorescent whitening agent comprising either a mixture of compounds of formulae ,1 a,, ,1 b, and ,1 c,, a compound of formula ,2, or a compound of formula ,5,. The compounds of the present invention are particularly advantageous in that they exhibit not only extremely high whitening ability, also in the presence of cationic polymers or residual amounts of anionic FWA's, but, in addition, in many cases highly desirable water solubilities and fastness properties. The following Examples serve to illustrate the invention without intending to be restrictive in nature; parts and percentages are by weight, unless otherwise stated. Percentage compositions of reaction mixtures are calculated as the areas under the curves of the respective HPLC spectra, observed at 350nm. 16.7g of 4.4'-bis [,4-N-mqrphoIino-e-chloro-l.1,2,3-triazin-a-yOaminolstilbene-22'-disulphonic acid disodium salt are added over 30 minutes with stirring at 25°C to 50ml of 3-N.N-dimethylamino-1-propylamine, whereby, during the addition, the temperature rises to 60°C. The temperature is then further increased to 10O°C and the mixture maintained at this temperature for a further 1 hour. Heating is then ceased, the mixture allowed to stand overnight at room temperature, then diluted with 25ml of water and evaporated under vacuum to approximately 30g. The resulting residue is dissolved in 50ml of water and the pH adjusted to 1.0 by addition of 20ml of concentrated hydrochloric acid. The pH is then raised to approximately 5 and the mixture stirred overnight at room temperature. The precipitated solids are filtered, washed with water and dried under vacuum at 60°C. There are obtained 14.9g of the compound of formula ,101, as pale yellow crystals with an active content of 83%. The starting material, 4,4'-bis [,4-N-morpholino-6-chloro-1,3l5-tria2in-2-yl,amino]stilbene-2,2,-disulphonic acid disodium salt of formula ,101a,, is prepared as follows: A solution of 120g of cyanuric chloride in 930ml of methyl ethyl ketone is added with stirring over 10 minutes at 5-10°C to 400g of ice/water. Then, during 70 minutes at a pH of from 4.5 to 5.0, 1042g of a 12% solution of M'-diaminostilbene^'-disulphonic acid and sodium carbonate are added such that no excess of 4,4'-diaminostilbene-2t2'-disulphonic acid is present. The mixture is stirred for a further 20 minutes at 5-10°C, after which time a total of 37.9ml of 20% aqueous sodium carbonate solution is consumed. The mixture is warmed to 15-20°C and the pH adjusted to 7.0 by addition of 20% aqueous sodium carbonate solution. 28.0g of morpholine are then added drop wise over 10 minutes, the mixture warmed to 70-75°C during 60 minutes and stirring continued for 30 minutes at this temperature, the pH being maintained at 7.0-7.5 by addition of a total of 46.9ml of 50% aqueous sodium hydroxide solution. The temperature is then raised to 90°C and the methyl ethyl ketone distilled off. The reaction mixture is then slowly cooled to 25°C over 60 minutes, the precipitated solids filtered, washed with 5% brine and dried under vacuum at 60°C. There are obtained 232.2 g of the compound of formula 8.9g of 4,4'-bis [,4-bis-,2-hydroxethyl,amino-6-chloro-1,3,5-tria2in-2-yl,amino]stilbene-2,2,-disulphonic acid disodium salt, obtained by an analogous process to that described for compound ,101a, in Example 1, are added over 10 minutes with stirring at 25°C to 25ml of 3-NtN-dimethylamino-1-propylamine, whereby, during the addition, the temperature rises to 45°C. The temperature is then further increased to 100°C and the mixture maintained at this temperature for a further 1.75 hours. Heating is then ceased, the mixture allowed to stand overnight at room temperature, then diluted with 25ml of water and evaporated under vacuum to approximately 18g. The resulting residue is diluted with 50ml of water and the pH adjusted to 1.0 by addition of aqueous 17% hydrochloric acid. 90ml of acetone are then added, resulting in the formation of 2 phases. The aqueous phase is separated off in a separating funnel and the pH is then raised to 8.5 by addition of 4N aqueous sodium hydroxide solution. The precipitated solids are filtered, washed with water and dried under vacuum at 60°C. There are obtained 5.0g of the compound of formula ,102, as yellow crystals. By proceeding essentially as described in Example 2, but replacing the 4,4'-bis [,4-bis,2-hydroxyethyl,amino-6-chloro-1 ^.S-triazin^-yOamino^tilbene-^Z-disulphonic acid disodium salt by an equivalent quantity of 4,4'-bis [,4-bis,2-hydroxy-n-propyl,amino-6-chloro-1,3,5-triazin-2-yl,amino]stilbene-2,2'-disulphonic acid disodium salt, obtained by an analogous process to that described for compound ,101 a, in Example 1, there are obtained 6.4g of the compound of formula ,103, as pale yellow crystals 24.3g of 4,4'-bis [,4-N-morpholino-6-chloro-1 .3,-triazin4-yOaminoJstilbene-2,2-disulphonic acid disodium salt ,101a, are added over 15 minutes with stirring at 69.6g of 2-N,N-diethylamino-1-ethytamine. The resulting suspension is then heated to 115°C and the mixture maintained at this temperature for a further 2 hours. After diluting with 150ml of water, the pale brown solution is evaporated under vacuum and this procedure repeated twice. Addition of 100ml of water to the residue results in a beige suspension of pH 11.2. The pH is then adjusted to 12.8 by addition of 5ml of 50% aqueous sodium hydroxide solution, then lowered to 4 by addition of 35ml of concentrated hydrochloric acid, the yellow precipitate stirred for 30 minutes, filtered and washed with 1000ml of water. After drying under vacuum at 70°C, there are obtained 26.7g of the compound of formula ,104, as yellow crystals. By proceeding essentially as described in Example 4, but replacing the 2-N,N-diethylamino-1-ethylamine by an equivalent quantity of 3-N,N-diethylamino-1-propylamine, there are obtained 27.0g of the compound of formula ,105, as whitish beige crystals. By proceeding essentially as described in Example 4, but replacing the 4,4'-bis [,4-N-morpholino-6-chloro-1 t3,5-triazin-2-yl,amino]stilbene-2l2,-disulphonic acid disodium salt by an equivalent quantity of 4,4'-bis [,4-anilino-6-chloro-1I3,5-triazin-2-yl,amino]stilbene-2,2,-disulphonic acid disodium salt, obtained by an analogous process to that described for compound ,101a, in Example 1, there are obtained 19.9g of the compound of formula ,106, as beige crystals. By proceeding essentially as described in Example 4, but replacing the 4,4'-bis [,4-N-morpholino-e-chloro-I.S.S-triazin-Z-yOaminolstilbene-3,'-disulphonic acid disodium salt by an equivalent quantity of 4J4,-bis [,4-anilino-6-chloro-1f3I5-triazin-2-yl,amino]stilbene-2,2,-disuiphonic acid disodium salt and the 2-N,N-diethylamino-1-ethylamine by an equivalent quantity of 3-N,N-diethylamino-1 -propylamine, there are obtained 26.6g of the compound of formula ,107, as beige crystals. 9.5g of 4,4'-bis {44sulphonamidoanilinoJ-S-chloro-I4.S-triazin4yllaminoJstiibene4,4-disulphonic acid disodium salt, obtained by an analogous process to that described for compound ,101a, in Example 1, are added over 20 minutes with stirring at 90°C to 32.0g of 3-N,N-dimethylamino-1 -propylamine. The temperature is then further increased to 115-120°C and the mixture maintained at this temperature for a further 2 hours. Heating is then ceased, the mixture then diluted with 120ml of water and evaporated under vacuum. After repeating the latter procedure, the resulting residue is dissolved in 150ml of water and the pH adjusted to 12-13 by addition of aqueous sodium hydroxide. Subsequently, the pH is adjusted to 6 by addition of concentrated hydrochloric acid and the resulting precipitate filtered, washed with water and dried under vacuum at 70°C. There are obtained 8.4g of the compound of formula ,108, as paie yellow crystals. 10.0g of 4,4'-bis [,4anilino-e4hloro-I4.S-triazin-a-yOaminolstilbene-Z.4-disulphonic acid disodium salt are added over 15 minutes with stirring at 30°C to 30ml of 1,3-diaminopropane, whereby the temperature rises to 50°C. The yellow suspension is then heated to 80°C and stirring continued at this temperature for a further 90 minutes. After cooling, the mixture is poured into 300ml of water and the pH adjusted to 2 by addition of 65ml of concentrated _ hydrochloric acid. The aqueous liquors are decanted from the oily residue, which residue is ground with water in a mortar and then stirred for 2 hours at pH 5. The solids are filtered off, washed with 5% brine and dried under vacuum at 70°C, There are obtained 10.1g of the compound of formula ,109, as yellow crystals. By fo,,owing the procedure described in examp,e 9, but rep,acing the 4,4'-bis [,4-ani,ino-6-ch,oro-1 4.S-triazin4-yOamino,sti,bene44'-disuiphonic acid disodium sa,t by an equiva,ent quantity of 4,4,-bis {[4-,4-su,phonamidoani,ino,,6-ch,oro-1,3,5-t4ia2in-2-yI]amino}sti,bene-2,2,-disu,phonic acid disodium sa,t, 12.0g of the compound of formu,a ,110, are obtained as pa,e brown crysta,s. In a manner ana,ogous to that described in Examp,e 9, 8.5g of 4,4'-bis [,4-N-morpho,ino-6-ch,oro-1 .S.S-triazin4-yOaminojsti,bene44'-disu,phonic acid disodium sa,t are reacted with 30m, of 1,3-diaminopropane to yie,d 9.1 g of the compound of formu,a ,111, as ye,,ow crysta,s. Examp,e 12 A mixture of compounds of formu,ae 16.46g of 4,4'-bis [,4-ani,ino-6-ch,oro-1,3,5-triazin-2-y,,am acid disodium sa,t are added over 30 minutes with stirring at 50°C to a mixture of 33.95g of 3-N.N-dimethy,amino-1-propy,amine and 12.25g of 1,3-diaminopropane, wherby the temperature rises to 85°C. The ye,,owish brown viscous so,ution is then heated to 90°C and stirring continued for a further 5 hours at this temperature. After coo,ing, the mixture is poured into 300m, of water and the resu,ting ye,,ow so,ution of pH 11.4 a,,owed to stand overnight. The pH is then adjusted to 3 by addition of 85m, of concentrated hydroch,oric acid, the mixture stirred for a further 2 hours and the precipitated so,ids fi,tered, washed with 5% brine and dried under vacuum at 70°C. There are obtained 18.2g of the mixture of compounds of formu,ae containing 40% ,112a,, 44% ,112b, and 13% ,112c, as ye,,ow crysta,s. A so,ution of 120g of cyanuric ch,oride in 930m, of methy, ethy, ketone is added with stirring over 10 minutes at 5-10°C to 400g of ice/water. Then, during 70 minutes at a pH of from 4.5 to 5.0,1093g of a 12% so,ution of 4f4'-diaminosti,bene-2I2'-disu,phonic acid and sodium carbonate are added such that no excess of 4,4'-diaminosti,bene-2,2'-disu,phonic acid is present. The mixture is stirred for a further 10 minutes at 5-10°C, after which time a tota, of 21.2m, of 20% aqueous sodium carbonate so,ution is consumed. The mixture is warmed to 8-20°C and the pH adjusted to 7.5 by addition of 50% aqueous sodium hydroxide so,ution. A mixture of 29.9g of ani,ine and 28.0g of morpho,ine is then added drop wise over 10 minutes, the mixture warmed to 70°C during 60 minutes and stirring continued for 90 minutes at this temperature, the methy, ethy, ketone being disti,,ed off. A tota, of 54.2m, of 50% aqueous sodium hydroxide so,ution are required to maintain a pH of 7.5 during this period. The reaction mixture is then coo,ed to 30°C over 60 minutes and a,,owed to stand overnight at room temperature. The supernatant ,iquid is decanted off, the residue suspended in 750m, of 5% brine, warmed to 60°C and then s,ow,y coo,ed to 30°C over 60 minutes. The precipitated so,ids are fi,tered, washed with 5% brine and dried under vacuum at 70°C. There are obtained 259.1 g of a ye,,ow crysta,,ine product containing 27% of the compound of formu,a ,113a,, 46% ,113b, and 24% ,101 a,. Examp,e 14 A mixture of compounds of formu,ae By fo,,owing the procedure described in Examp,e 13, but rep,acing the 28.0g of morpho,ine by 33.7g of diethano,amine, there are obtained 287.3g of a ye,,ow crysta,,ine product containing 24% of the compound of formu,a ,113a,, 38% ,114b, and 30% ,114c,. • 30.0g of 4,4'-bis 4ani,ino-e-ch,oro-I.S.S-triazin4-yOaminoJsti,bene44'-disu,phonic acid disodium sa,t are added with stirring over 10 minutes at 80°C to 100.0g of 2-N,N-dimethy,amino ethano,. The beige suspension is then heated to 120°C and stirred for a further 1.5 hours at this temperature. After coo,ing to 100°C, the mixture is di,uted with 100m, of water and evaporated on a rotary evaporator. The residue ,56g, is taken up in 300m, of water, the pH of the ye,,owish brown suspension adjusted to 5 by addition of hydroch,oric acid and the mixture stirred for a further 1 hour. The precipitated so,ids are fi,tered, washed with water and dried under vacuum at 70°C. There are obtained 30.2g of the compound of formu,a ,115, as whitish beige crysta,s. Examp,e 16 A mixture of compounds of formu,ae A so,ution of 120g of cyanuric ch,oride in 930m, of methy, ethy, ketone is added with stirring over 10 minutes at 5-10°C to 400g of ice/water. Then, during 70 minutes at a pH of from 4.5 to 5.0, 978g of a 12% so,ution of 4,4'-diaminosti,bene-2,2,-disu,phonic acid and sodium carbonate are added such that no excess of 4,4,-diaminosti,bene-2,2,-disu,phonic acid is present. The mixture is stirred for a further 10 minutes at 5-10°C, after which time a tota, of 24.2m, of 20% aqueous sodium carbonate so,ution is consumed. The mixture is warmed to 10-20°C and the pH adjusted to 7.5 by addition of 50% aqueous sodium hydroxide so,ution. 29.9g of ani,ine are then added drop wise over 10 minutes, the mixture warmed to 30°C and stirring continued for 30 minutes at this temperature. A so,ution of 17.2g of ammonium ch,oride in 50m, of water is then added drop wise over 15 minutes and the resu,ting ye,,ow suspension heated to 70°C. After stirring for a further 60 minutes, 100m, of 25% aqueous ammonia are added, the mixture stirred for 30 minutes and the methy, ethy, ketone is fina,,y disti,,ed off. The resu,ting mixture is coo,ed to 30°C, the precipitated so,ids fi,tered, washed with a ,itt,e water, then with 5% brine and dried under vacuum at 70°C. There are obtained 199.7g of a ye,,ow crysta,,ine product consisting of a mixture of compounds containing 26% ,113a,, 26% ,116b, and 36% ,116c,. 30.0g of the mixture of compounds of formu,ae ,113a,, ,113b, and ,101 a,, obtained as described in Examp,e 13, are added with stirring over 20 minutes at 45°C to 100m, of 3-N,N-dimethy,amino-1 -propy,amine. The mixture is warmed to 120°C and stirred for a further 1 hour at this temperature. After coo,ing to 90°C, 100m, of water are added and the reaction mixture evaporated on a rotary evaporator. The residue is disso,ved in 250m, of water, the pH adjusted to 5 by addition of concentrated hydroch,oric acid and the precipitated so,ids fi,tered, washed with water and dried under vacuum at 70°C. There are obtained 27.2g of a ye,,ow crysta,,ine product, which is a mixture of compounds containing 26% ,112a,, 45% ,117b, and 23% ,101,. By fo,,owing the procedure described in Examp,e 15, but rep,acing the 4,4'-bis [,4-ani,ino-6-ch,oro-1 4.S-triazin4-y,Jaminojsti,bene4.Z'-disu,phonic acid disodium sa,t by 30g of 4,4'-bis [,4-amino-6-ch,oro-1,3,5-triazin-2-y,,amino]sti,bene-2,2'-disu,phonic acid disodium sa,t, obtained by an ana,ogous process to that described for compound ,101a, in Examp,e 1, there are obtained 30.0g of the compound of formu,a ,118, as ye,,ow crysta,s. , By fo,,owing the procedure described in Examp,e 15, but rep,acing the 4,4'-bis [,4-ani,ino-6-ch,oro-1 AS-triazin-a-yOamino,sti,bene-Z4'-disu,phonic acid disodium sa,t by 30g of 4,4'-bis [,4-N-morpho,ino-6-ch,oro-1 ,3,5-triazin-2-y,,amino]sti,bene-2,2'-disu,phonic acid disodium sa,t ,101a,, there are obtained 30.0g of the compound of formu,a ,119, as ye,,ow crysta,s. 30.0g of the mixture of compounds of formu,ae ,113a,, ,113b, and ,113c,t obtained as described in Examp,e 13, are added with stirring over 45 minutes at 80°C to 100m, of 2-N,N-dimethy,amino-1-ethano,. The mixture is stirred for a further 2 hours at 80°C and then di,uted with 100m, of water and the reaction mixture evaporated on a rotary evaporator. The residue is disso,ved in 100m, of water, the pH adjusted to 5.5 by addition of 10m, of concentrated hydroch,oric acid and the Supernatant ,iquid decanted off. The residue is ground in a mortar with 150m, of 5% brine, stirred overnight and the precipitated so,ids fi,tered, washed with 5% brine water and dried under vacuum at 70°C. There are obtained 28.6g of a ye,,ow crysta,,ine product, which is a mixture of compounds containing 21% ,115,, 35% ,120b, and 19% ,119,. Examp,e 21 A mixture of compounds of the formu,ae By fo,,owing the procedure described in Examp,e 20, but rep,acing the 30.0g of the mixture of compounds of formu,ae ,113a,, ,113b, and ,113c, by 30.0g of the mixture of compounds of formu,ae ,114a,, ,114b, and ,114c,, prepared as described in Examp,e 14, there are obtained 27.3g of a mixture of compounds containing 26% ,115,, 39% ,121b, and 29% ,121c, in ye,,ow crysta,,ine form. By fo,,owing the procedure described in Examp,e,3, but rep,acing the morpho,ine by an equiva,ent quantity of di-isopropano,amine, 210.5g of a mixture of compounds containing 31% of the compound of formu,a ,113a,, 45% ,122b, and 20% ,122c, is obtained, as ye,,ow crysta,s. Examp,e 23 A mixture of compounds of formu,ae By fo,,owing the procedure described in Examp,e13, but rep,acing the morpho,ine by an equiva,ent quantity of monoethano,amine, 244g of a mixture of compounds containing 26% of the compound of formu,a ,113a,, 40% ,123b, and 33% ,123c, is obtained, as ye,,ow crysta,s. By fo,,owing the procedure described in Examp,e 15, but rep,acing the 4t4,-bis [,4-ani,ino-6-ch,oro-I4.S-triazin4-yOaminoJsti,bene44'-disu,phonic acid disodium sa,t by 30g 4,4'-bis [,4-bis-,2-hydroxethy,,amino-6-ch,oro-1,3,5-tria2in-2-y,,amino]sti,bene-2,2,-disu,phonicacid disodium sa,t, there are obtained 27.3g of the compound of formu,a ,124, as ye,,ow crysta,s. To a stirred mixture of 150m, of water, 150m, of dioxane and 40.7g of ethy,ene diamine, heated to 70-75°C, 40.0g of 4,4,-bis [,4-amino-6-ch,oro-1 ,3,5-triazin-2-y,,amino]stiIbene-2,2'-disuiphonic acid disodium sa,t are added over 30 minutes. The brown so,ution is then heated to 88°C and stirring continued for a further 2 hours. After coo,ing to 70°C, the pH is adjusted to 5.5 by addition of 115m, of concentrated hydroch,oric acid and the precipitated so,ids fi,tered at 60°C and washed with a ,itt,e water. The fi,ter cake is suspended in 350m, of water, 50% aqueous sodium hydroxide so,ution added to pH 11 and the resu,ting ye,,ow so,ution stirred for 1 hour. The pH is adjusted to 5 by addition of concentrated hydroch,oric acid, the ye,,ow precipitate fi,tered, washed with water and dried under vacuum at 70°C. There are obtained 31.5g of the compound of formu,a ,125, as ye,,ow crysta,s. By proceeding essentia,,y as described in Examp,e 25, but rep,acing the 40.0g of 4,4'-bis [,4-amino-e-ch,oro-I4.S-triazin4-yOaminoJsti,bene44'-disuiphdnic acid disodium sa,t by 40.0g of 4,4'-bis [,4-ani,ino-6-ch,oro-1 AS-triazin4-yOaminojsti,bene44'-disu,phonic acid disodium sa,t, there are obtained 30.4g of the compound of formu,a ,126, as ye,,ow crysta,s. By proceeding essentia,,y as described in Examp,e 25, but rep,acing the 40.7g of ethy,ene diamine by 91.6g of N-,3-aminopropy,,diethano,amine, there are obtained 50.4g of the compound of formu,a ,127, as ye,,ow crysta,s. By reacting 40.0g of the mixture of compounds of formu,ae ,113a,f ,113b, and ,113c,, obtained as described in Examp,e 13, with 100m, of 3-N,N-dimethy,amino-1-propy,amine, 4 essentia,,y as described in Examp,e 20, there are obtained 33.8g of ye,,owish brown crysta,s of a mixture of compounds containing 25% of the compound of formu,a ,112a,, 39% ,128b, and 27% ,102,. By proceeding essentia,,y as described in Examp,e 25, but rep,acing the 40.0g of 4f4'-bis [,4-amino-6-ch,oro-1,3I5-triazin-2-y,,amino]sti,bene-2,2,-disu,phonic acid disodium sa,t by 40.0g of 4,4'-bis [,4-ani,ino-6-ch,oro-1,3,5-triazin-2-y,,amino]sti,bene-2,2,-disu,phonic acid disodium sa,t and the 40.7g of ethy,ene diamine by 68.1 g of 2-,3-aminopropy,amino, ethano,, there are obtained 35.8g of the compound of formu,a ,129, as ye,,ow crysta,s. By proceeding essentia,,y as described in Examp,e 25, but rep,acing the 40.0g of 4,4'-bis [,4-amino-e-ch,oro-,.S.S-triazin4-yOaminoJsti,bene44'-disu,phcnic acid disodium sa,t by 35.0g of 4,4'-bis [{4-ethano,amino-6-ch,oro-1 .S.S-triazin4-yOaminoJstiibene-Z4'-disu,phonic acid disodium sa,t and the 40.7g of ethy,ene diamine by 47.0g of 3-N,N-dimethy,amino-1-propy,amine, there are obtained 39.3g of the compound of formu,a ,130, as ye,,ow crysta,s. Treatment of 30.0g of 4,4'-bis [,4-ani,ino-6-ch,oro-1 ,3,5-triazin-2-y,,amino]sti,bene-2,2'-disu,phonic acid disodium sa,t with 90m, of N-,2-hydroxyethy,, ethy,ene diamine, essentia,,y as described in Examp,e 9, resu,ts in 28.0g of the compound of formu,a ,131, as beige crysta,s. By fo,,owing the procedure described in Examp,e13, but rep,acing the morpho,ine by an equiva,ent quantity of 2-N-methy,aminoethano,, 213.3g of a mixture of compounds containing 26% of the compound of formu,a ,113a,, 34% ,132b, and 32% ,132c, is obtained, as ye,,ow crysta,s. By fo,,owing the procedure described in Examp,e13, but rep,acing the morpho,ine by an equiva,ent quantity of 1-aminopropan-2-o,, 188.5g of a mixture of compounds containing 33% of the compound of formu,a ,113a,, 40% ,133b, and 23% ,133c, is obtained, as ye,,ow crysta,s. A so,ution of 120g of cyanuric ch,oride in 930m, of methy, ethy, ketone is added with stirring over 10 minutes at 5-10°C to 400g of ice/water. Then, during 70 minutes at a pH of from 4.5 to 5.0,1083g of a 12% so,ution of 4,4,-diaminosti,bene-2,2,-disu,phonic acid and sodium carbonate are added such that no excess of 4,4,-diaminosti,bene-2,2,-disu,phonic acid is present. The mixture is stirred for a further 10 minutes at 5-10°C, after which time a tota, of 29.8m, of 20% aqueous sodium carbonate so,ution is consumed. The mixture is warmed to 10-20°C and the pH adjusted to 7.0-7.5 by addition of 50% aqueous sodium hydroxide so,ution. 52.5g of 1-amino propan-2-o, are then added drop wise over 10 minutes, the mixture warmed to 70°C over 1 hour and stirring continued for a further 90 minutes at this temperature, the methy, ethy, ketone being disti,,ed off, then coo,ed to 50°C during 30 minutes, then to 25°C during a further 30 minutes, stirred for a further 3 hours at this temperature and, fina,,y, a,,owed to stand overnight at room temperature. The pH is maintained at 7.0-7.5 during the entire period, whereby a tota, of 53.4m, of a so,ution of 50% aqueous sodium hydroxide so,ution is consumed. The precipitated so,ids are fi,tered washed with water, then with 2.5% brine and dried under vacuum at 70°C. There are obtained 230.6g of the compound of formu,a as ye,,ow crysta,s. To a mixture of 150m, of water, 150m, of dioxane and 43.1 g of 3-N,N-dimethy,amino-1-propy,amine, previous,y warmed to 70°C, 35.0g of the compound of formu,a ,134a, are added with stirring. The ye,,owish brown so,ution is warmed to 86-88°C and stirring continued for 90 minutes at this temperature. After coo,ing to 70°C, 100m, of water are added and the pH adjusted to 5.0 by addition of 70m, of concentrated hydroch,oric acid. After adjusting the pH to 1.5 and coo,ing to 10°C, 25g of sodium ch,oride are added and the mixture stirred overnight. The mixture is then evaporated on a rotary evaporator and the resu,ting viscous residue added in portions to 400m, of acetone. The supernatant ,iquids are discarded and the procedure repeated unti, a crysta,,ine product resu,ts. After fi,tering, the so,ids are stirred overnight in 200m, of water, the supernatant ,iquids discarded, the residue evaporated on a rotary evaporator and fina,,y dried under vacuum at 70°C. There are obtained 13,0g of the compound of formu,a ,134, as pa,e ye,,ow crysta,s. Treatment of 30.0g of 4,4'-bis [,4-ani,ino-6-ch,oro-1,3t5-triazin-2-y,,amino]sti,bene-2t2,-disu,phoniG acid disodium sa,t with 100m, of 2,2'-,ethy,enedioxy,-diethy,ene diamine, essentia,,y as described in Examp,e 9t resu,ts in 34.0g of the compound of formu,a ,135, as pa,e brown crysta,s. By fo,,owing the procedure described in Examp,e 1 for the preparation of the compound of formu,a ,101a,, but rep,acing the morpho,ine by an equiva,ent quantity of p-phenetidine, there are obtained 232.7g of the compound of formu,a as greenish ye,,ow crysta,s. By proceeding essentia,,y as described in Examp,e 25, but rep,acing the 40.0g of 4,4'-bis [,4-amino-S-ch,oro-,44triazin4-yOamino,sti,bene44'-disu,phonic acid disodium sa,t by 35.0g of the compound of formu,a ,136a,, 27.2g of the compound of formu,a ,136, are obtained as ye,,ow crysta,s. By proceeding essentia,,y as described in Examp,e 25, but rep,acing the 40.0g of 4,4,-bis [,4-amino-6-ch,oro-1 .3,-triazin-a-yOamino,sti,bene-3,'-disu,phonic acid disodium sa,t by 40,0g of 4,4,-bis [,4-ani,ino-6-ch,oro-1,3,5-triazin-2-y,,amino]sti,bene-2,2'-disu,phonic acid disodium sa,t and the 40.7g of ethy,ene diamine by 35.5g of 1,2-propy,ene diamine, there are obtained 34.7g of the compound of formu,a ,137, as ye,,ow crysta,s. By proceeding essentia,,y as described in Examp,e 25, but rep,acing the 40.0g of 4,4'-bis [,4-amino-e-ch,oro-I4.S-triazin4-yOaminoJsti,bene44'-disu,phonic acid disodium sa,t by 30.0g of 4,4'-bis [,4-ani,ino-6-ch,oro-1,3,5-triazin-2-y,,amino]sti,bene-2,2'-disu,phonic acid disodium sa,t and the 40.7g of ethy,ene diamine by 48.3g of 1,2-diamincyc,ohexane, there are obtained 27.1g of the compound of formu,a ,138, as ye,,ow crysta,s. By proceeding essentia,,y as described in Examp,e 13, but rep,acing the mixture of 29.9g of ani,ine and 28.0g of morpho,ine by 89.1 g of 2-ani,inoethano,, there are obtained 281.5g of the compound of formu,a as ye,,ow crysta,s. To 150m, of water, previous,y warmed to 70-75°C, 35.0g of the compound of formu,a ,139a, are added. The resu,ting ye,,ow so,ution is then treated with 12.6g of diethy,amino-propy,amine and the mixture stirred for 4 hours at 95-97°C, the pH being maintained at 10.0-10.5 by addition of a tota, of 1.5m, of 4N aqueous sodium hydroxide so,ution. After coo,ing to 70°C, the pH is adjusted to 4.0 by addition of 6.5mf of concentrated hydroch,oric acid and the precipitated so,ids fi,tered, washed with water and dried under vacuum at 80°C. There are obtained 37.4g of the compound of formu,a ,139, as ye,,ow crysta,s. Treatment of 25.0g of 4,4'-bis {[4-,4-su,phonamidoaniIino,-6-ch,oro-1 4.S-triazin-a-yI]amino}sti,bene-2f2'-disuIphonic acid disodium sa,t ,see Examp,e 8, with 9.6g of 3-diethy,amino-1 -propy,amine by an ana,ogous process to that described for compound ,139, in the previous examp,e, resu,ts in the formation of 24.0g of the compound of formu,a ,140, as ye,,ow crysta,s. By proceeding essentia,,y as described in Examp,e 30, but rep,acing the 3-N.N-dimethy,amino-1-propy,amine by 3-N,N-diethy,amino-1 -propy,amine, there are obtained 40.4g of the compound of formu,a ,141, as ye,,ow crysta,s. Treatment of. 65.2g of 4f4,-bis [,4-bis ,2-hydroxy-n-propy,,amino-6-ch,oro-1,3,5-triazin-2-y,,amino]stiIbene-2,2'-disu,phonic acid disodium sa,t ,see Examp,e 3, with 13.9g of 3-diethy,amino-1-propy,amine by an ana,ogous process to that described for compound ,139, in Examp,e 39, resu,ts in the formation of 28.8g of the compound of formu,a ,142, as ye,,ow crysta,s. Treatment of 25g of 4,4'-bis [,4-bis-,2-hydroxethy,,amino-6-ch,oro-1,3f5-tria2:in-2-yOaminojsti,bene4'-disu,phonic acid disodium sa,t ,see Examp,e 2, with 11.6g of 3-diethyIamino-1-propy,amine by an ana,ogous process to that described for compound ,139, in Examp,e 39, resu,ts in the formation of 24.1 g of the compound of formu,a ,143, as ye,,ow crysta,s. Treatment of 25g of the compound of formu,a ,134a, ,see Examp,e 34, with 9.95g of 3-diethy,amino-1 -propy,amine by an ana,ogous process to that described for compound ,139, in Examp,e 39, resu,ts in the formation of 24.6g of the compound of formu,a ,144, as ye,,ow crysta,s. By proceeding essentia,,y as described in Examp,e 13, but rep,acing the mixture of 29.9g of ani,ine and 28.0g of morpho,ine by 84.0g of 2-ethy,-1-hexy,amine, there are obtained 270.7g of the compound of formu,a as ye,,owish beige crysta,s. Treatment of 25.0g of the compound of formu,a ,145a, with 10.5g of 3-diethy,amino-1-propy,amine by an ana,ogous process to that described for compound ,139, in Examp,e 39, resu,ts in the formation of 26.7g of the compound of formu,a ,145, as pa,e ye,,ow crysta,s. By proceeding essentia,,y as described in Examp,e 13, but rep,acing the mixture of 29.9g of ani,ine and 28.0gof morpho,ine by 64.3g of 2-amino-2-methy,-1-propanoI, there are obtained 162.4g of the compound of formu,a as ye,,ow crysta,s. Treatment of 25g of the compound of formu,a ,146a, with 11.6g of 3-diethy,amino-1-propy,amine by an ana,ogous process to that described for compound ,139, in Examp,e 39, resu,ts in the formation of 29.2g of the compound of formu,a ,146, as beige crysta,s. By proceeding essentia,,y as described in Examp,e 25, but rep,acing the 40.0g of 4,4'-bis [,4-amino-e-ch,oro-,.1,2,3-triazin-2-y,Jaminojsti,bene-2,2'-disu,phonic acid disodium sa,t by 35.0g of 4,4'-bis [,4-ani,ino-6-ch,oro-1,3,5-triazin-2-y,,amino]sti,bene-2f2,-disu,phonic acid disodium sa,t and the 40.7g of ethy,ene diamine by 44.6g of diethy,ene triamine, there are obtained 37.1 g of the compound of formu,a ,147, as ye,,ow crysta,s. By reacting 25.0g of the mixture of compounds of formu,ae ,113a,, ,123b, and ,123c,, obtained as described in Examp,e 23, with 11.9g of 3-N,N-diethy,amino-1-propy,amine, by an ana,ogous process to that described for compound ,139, in Examp,e 39, there are obtained 25.9g of a mixture of compounds containing 29% of the compound of formu,a ,107,, 42% ,148b, and 28% ,130, as ye,,ow crysta,s. App,ication Examp,es The various f,uorescent whitening agents ,FWA's, are disso,ved in 25m, of a 9:1 mixture of dimethy, su,phoxide/water, the pH adjusted to approximate,y 10 by addition of 4IM aqueous sodium hydroxide so,ution and the so,utions made up to 50m, with water. To a fibre dispersion consisting of 70 parts birch and 30 parts pine Kraft fibre with a degree of refining of 35° SR, 10% ca,cium carbonate ,Hydrocarb 60, is added as fi,,er. Sufficient of the FWA so,utions are then added such that the FWA concentration, based on the weight of the pu,p fibre, is 0.2%. The FWA is a,,owed to exhaust for 15 minutes, 0.03% of a cationic po,yacry,amide ,Perco, 292, added as retention auxi,iary and the hand sheet formed immediate,y by means of the Rapid-Koethen system. The degrees of whiteness of the sheets ,W CIE, are then measured by SCAN-P66-93 using a spectrophotometer. The resu,ts of the measurements are summarized in the fo,,owing Tab,e 1. Tab,e 1 The above resu,ts c,ear,y demonstrate the exce,,ent whitening effects of the f,uorescent whitening agents of the invention. Claims 1. A fluorescent whitening agent, which comprises a mixture of compounds of the formulae in which A* represents a group of the formula wherein A represents -X-Y-NR3R4 and C is-NR1R2and B* represents a group of the formula D represents -NR5R6 and E represents -X1Y1NR1R8, whereby X and X1 each, independently of each other, represent -O- or -NH-, Y and Y1 each, independently of each other, represent a straight-chain C2-C8alkylene or branched C3-C8alkylene chain, which may be interrupted by one or two nitrogen, oxygen or sulphur atoms or represent a 5- or 6-membered cycioaliphatic ring, R1. R2, R5 and R6 each independently of each other, represenrhydrogen, C1-8alkyl, C2-C4hydroxyalkyl, C1-4alkoxyC1-4alkylt phenyl, which is unsubstituted or substituted by halogen, C1-4aIkoxy, C1-4alkyl or sulphonamido, or R1 and R2 and /or R5 and R6l together with the nitrogen atom to which they are attached, complete a morpholino- piperidino- or pyrrolidino-ring, R3. R4. R7 and R8, each independently of each other, represent hydrogen, C1-4aIkyl, C2-C4hydroxyaIkyl or R3 and R4 and/or R7 and R8, together with the nitrogen atom to which they are attached, complete a morpholino-, piperidino- or pyrrolidino-ring and M represents hydrogen, an alkaline or alkaline earth metal, ammonium or alkylammonium. 2. A fluorescent whitening agent, according to claim 1, which comprises a mixture of compounds of the formulae in which X, Y, R1 R2l R3, R4, R5t R6 and M are as defined in claim 1. 3. A fluorescent whitening agent, according to claim 1, which comprises a mixture of compounds of the formulae in which X, Xu Y, Y1, Rl R2, R3, R4, R7) Ra and M are as defined in claim 1. 4. A compound of formula II I TV I 111*1 I X1, Y, Y1, R,, R2, R3, R4, RS, R5, R7, Ra and M are as defined in claim 1. 5. A compound of the formula in which R9 and R10, each independently of each other, represent hydrogen or C1-4hydroxyalkyl and Y, Yi, R1, R2l R3, R4, R5. Re. and M are as defined in claim 1, with the proviso that when Y and Y, both represent -CH2CH2CH2-, R1 and R5 are both phenyl and R2 and R6 are both hydrogen, R3| R4, R9 and R10 are not all -CH2CH2OH. 6. A process for the preparation of a mixture of compounds of formulae (1a), (1b) and (1c), according to claim 1, by reacting, under known reaction conditions, cyanuric chloride, successively, in any desired sequence, with each of 4,4,-diaminostilbene-2,2'- disulphonic acid, amino compounds of formulae R1R2NH and RSR6NH or mixtures thereof and compounds of formulae R3R4YXH and RyRaY^H or mixtures thereof, X, X1( Y, Ytf Rtl R2, R3, R4, R5, R6. R7 and R8 being as defined in claim 1. 7. A process for the preparation of a compound of formula (2), according to claim 4, by reacting, under known reaction conditions, cyanuric chloride, successively, in any desired sequence, with each of 4,4,-diaminostilbene-2,2'- disulphonic acid, an amino compound of formula R1R2NH, an amino compound of formula R5R6NH, a hydroxy compound of formula R3R4NYOH and a compound of formula RrRaNYtXiH, XI, Y, Y1, R1, R2, R3, R4, R5, Re. R7 and R8 being as defined in claim 1. 8. A process for the preparation of a compound of formula (3), according to claim 5, by reacting, under known reaction conditions, cyanuric chloride, successively, in any desired sequence, with each of 4,4,-diaminostilbene-2,2,- disulphonic acid, an amino compound of formula R1R2NH, an amino compound of formula R5R6NH, an amino compound of formula R3R4NYNH2 and a compound of formula R9RioNY1NH2l Y, Y1, R,, R2, R3i R4. Rsr Re. R9 and R10being as defined in claims 1 and 5. 9. A compound of the formula or a mixture comprising compounds of the formulae in which R11 and R12l each independently of each other, represent hydrogen, C1-4alkyl, C2-C4hydroxyalkyl, C1-4alkoxyC1-4alkyl or, together with the nitrogen atom to which they are attached, complete a morpholino-, piperidino- or pyrrolidino-ring, R13 represents phenyl, which is unsubstituted or substituted* by halogen, C1-C4alkoxy) C1-4aIkyl or sulphonamido and M represents hydrogen, an alkaline or alkaline earth metal, ammonium or alkyl ammonium. 10. A process for the preparation of a compound of formula (4a) or a mixture of compounds of formulae (4a), (4b) and (4c), according to claim 9, by reacting, under known reaction conditions, cyanuric chloride, successively, in any desired sequence, with each of 4,4'-diaminostiibene-2,2'- disulphonic acid, an amino compound of formula R11R12 NH and an amino compound of formula R13NH2 or with a mixture of amino compounds R11R12NH and R13NH2, R11 R12 and R13 being as previously defined in claim 9. 11. Use of the compound of formula (4a), according to claim 9, for the preparation of a compound of formula (2), according to claim 3, in which, in formula (2), R1 and R2 each independently of each other, represent hydrogen, C1-4alkyl, C2-C4hydroxyalkyl, C1-4alkoxyC1-4aIkyl or, together with the nitrogen atom to which they are attached, complete a morpholino-, piperidino- or pyrrolidino-ring, R5 represents phenyl, which is unsubstituted or substituted by halogen, C1-4alkoxy, C1-4alkyl or sulphonamido, R6 represents hydrogen and X1f Y, Y1f R3, R4, R7l Rs and M are as defined in claim 1; for the preparation of compound of formula (3), according to claim 5, in which, in formula (3), R1 and R2 each independently of each other, represent hydrogen, C1-4alkyl, C2-C4hydroxyaIkyi, C1-4alkoxyC1-4alkyl or, together with the nitrogen atom to which they are attached, complete a morpholino-, piperidino- or pyrrolidino-ring, R5 represents phenyl, which is unsubstituted or substituted by halogen, C1-4alkoxy, C1-4alkyl or sulphonamido, R6 represents hydrogen and Y, Y1( R3| R4,. R9, R10I and M are as previously defined in claims 1 and 5 respectively or use of the mixture of compounds of formulae (4a)t (4b) and (4c), according to claim 9, for the preparation of a mixture of compounds of formulae (1a), (1b) and (1c), according to claim 1, in which, in formulae (1a), (1b) and (1c), Ri and R2 each independently of each other, represent hydrogen, C1-4alkyl, C2-C4hydroxyalkyl, C1-4alkoxyC1-4alkyl or, together with the nitrogen atom to which they are attached, complete a morpholino-, piperidino- or pyrrolidino-ring, R5 represents phenyl, which is unsubstituted or substituted by halogen, C1-4aIkoxy, C1-4alkyl or sulphonamido, R6 represents hydrogen and X, Xu Y, Yt, R3(R4, R7, Ra and M are as defined in claim 1. 12. Use of the mixture of compounds of formulae (1a), (1b) and (1c), according to claim 1, for the fluorescent whitening of paper. 13. Use of the compound of formula (2), according to claim 4, for the fluorescent whitening of paper. 14. Use of the compound of formula Ru and R1Sl each independently of each other, represent hydrogen, C1-4alkyl or C2-C4hydroxyalkyl and Y, Y1,R1,R2l R3l R4|R5, R6| and M are as defined in claim 1, for the fluorescent whitening of paper. 15. Paper, which has been treated with a fluorescent whitening agent comprising either a mixture of compounds of formulae (1a), (1b) and (1c), according to claim 1, a compound of formula (2), according to claim 4 or a compound of formula (5), according to claim 14.

Documents:

1295-chenp-2005-abstract.pdf

1295-chenp-2005-claims.pdf

1295-chenp-2005-correspondnece-others.pdf

1295-chenp-2005-correspondnece-po.pdf

1295-chenp-2005-description(complete).pdf

1295-chenp-2005-form 1.pdf

1295-chenp-2005-form 26.pdf

1295-chenp-2005-form 3.pdf

1295-chenp-2005-form 5.pdf

1295-chenp-2005-form18.pdf

1295-chenp-2005-pct.pdf