GB2313850A

GB2313850A - Triazine based UVA compounds as quenchers in paper making processes

Info

Publication number: GB2313850A
Application number: GB9710863A
Authority: GB
Inventors: Peter Rohringer; Dieter Reinehr; Robert Hochberg; Georges Metzger
Original assignee: Ciba Geigy AG; Ciba Spezialitaetenchemie Holding AG
Current assignee: Novartis AG; BASF Schweiz AG
Priority date: 1996-06-04
Filing date: 1997-05-28
Publication date: 1997-12-10
Also published as: GB9710863D0

Abstract

A process for the inhibition (quenching) of the effect of an anionic fluorescent whitening agent on a substrate such as paper comprises treating the substrate with a triazine UVA compound, some of which are new compounds.

Description

Use of triazine-based UVAs for use as auenchers in paDer-makina processes The present invention relates to a process for inhibiting (quenching) the effect of anionic fluorescent whitening agents on substrates, especially on fibre materials, by treating the substrates with certain triazine-based ultra-violet absorption agents (UVAs), some of which are new compounds.

The fluorescent whitening effect exerted by fluorescent whitening agents on fibre materials treated with the said by fluorescent whitening agents, provides a valuable and aesthetically appealing whiteness improvement in the appearance of fibre materials so treated.

Particularly in the paper industry, however, there are situations in which the fluorescent whitening effect exerted by fluorescent whitening agents can lead to problems. For example, many paper-producing machines are required to produce, altemately, whitened and non-whitened paper. Problems arise when, after the machine has been used to produce whitened paper1 it is subsequently required for the production of non-whitened paper. In these circumstances, residual fluorescent whitening agent from the production of whitened paper remains on the machine parts and contaminates the paper obtained in the subsequent production of non-whitened paper.

It is possible, of course, to thoroughly clean the paper machine and its associated recycling systems whenever it has been used to produce whitened paper and is then immediately to be used to produce non-whitened paper. Such thorough cleaning is expensive, however, and impairs production capacity.

It has already been proposed, in DE-A-2 448 293, to apply a quencher compound to paper material which is not be whitened before or after sheet formation. Such quencher compounds have also been suggested for addition to whitened used paper from which nonwhitened paper is to be produced.

The quencher compounds used in DE-A-2 448 293 are water-soluble acid addition salts or quaternary ammonium salts of compounds which contain a group of formula:

in which the substituents on the phenyl nucleus are in m- or p-position to one another.

Most modem paper-making processes, however, are operated under neutral pH conditions and the compounds of DE-A-2 448293 are unsatisfactory for such use since they only partly absorb on to the fibre under neutral application conditions. As a consequence, nonabsorbed quencher compound is undesirably discharged into the waste water. Moreover, the compounds of DE-A-2 448 293 tend to flocculate, which is disadvantageous for use in the awet-end" (paper formation) part of the paper-making process.

Surprisingly, it has now been found that triazine-based ultra-violet absorption agents (UVAs), when used as quenchers in paper-making processes, provide better absorption on to the fibre, lower waste water contamination and lower influence on dispersion stability (lower tendency to flocculate), relative to the compounds of DE-A-2 448 293.

Accordingly, the present invention provides a process for the inhibition (quenching) of the effect of an anionic fluorescent whitening agents on a substrate, comprising treating the substrate with a triazine UVA compound.

One preferred class of triazine UV absorbers is that having the formula:

in which at least one of R11 R2 and R3 is a radical of formula:

in which R4, R5 and R6, independently, are hydrogen; C1-C12alkoxy; hydroxy; -O-CH2-CO-NH-CH20H; SO3M in which M is hydrogen, sodium, potassium, ammonium, mono-, di-, tri- or tetra-C1-C4alkylammonium, mono-, di- or tri-C1-C4hydroxyalkylammonium or ammonium that is di- or tri-substituted by a mixture of C1-C4alkyl and C14hydrnxyalkyl groups; or

in which n is an integer from 2 to 6 and is preferably 2 or 3; V1 and Y2, independently, are C,-C4alkyl optionally substituted by halogen, cyano, hydroxy or C1-C4alkoxy or V1 and Y2, together with the nitrogen atom to which they are each attached, form a 5-7 membered heterocyclic ring, preferably a morpholine, pyrrolidine, piperidine or hexamethyleneimine ring; Y3 is hydrogen, C3-C4alkenyl or Ct-C4alkyl optionally substituted by cyano1 hydroxy or Cl-C4alkoxy or V11 Y2 and Y3, together with the nitrogen atom to which they are each attached, form a pyridine or picoline ring; and X1 is a colourless anion, preferably CH3OSO3- or C2HsOSO3~; and the remaining substituent(s) R1, R2 and R3 are, independently, halogen, preferably chlorine, C1-C12alkoxy or phenyl, the phenyl substituent being optionally substituted by one or more of hydroxy, C1-C12-alkoxy, -O-CH2-CO-NH-CH2OH, SO3M in which M has its previous significance.

In the compounds of formula (1), C1-C4alkyl groups Y1, Y2 and V3 may be methyl, ethyl, npropyl, isopropyl, n-butyl, isobutyl, tert.-butyl, methyl and ethyl being preferred C1-C12Alkoxy groups R1, R2, R31 R4, Rs and Re may be, e.g., methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, tert.-butoxy, n-amyloxy, n-hexoxy, n-heptoxy, n-octoxy, isooctoxy, n-nonoxy, n-decoxy, n-undecoxy or n-dodecoxy, methoxy and ethoxy being preferred.

The alkyl radicals in the mono-, di-, tri- or tetra-C1-C4aikylammonium groups M are preferably methyl. Mono-, di- or tri-C1-C4hydroxyalkylammonium groups M are preferably those derived from ethanolamine, diethanolamine or tri-ethanolamine. When M is ammonium that is di- or tri-substituted by a mixture of C1-C4alkyl and C1-C4hydroxyalkyl groups, it is preferably N-methyl-N-ethanolamine or N,N-dimethyl-N-ethanolamine. M is preferably, however, hydrogen or sodium.

Preferred compounds of formula (1) are those having the formulae:

The compounds of formula (1) are known and may be prepared e.g. by the method described in U.S.Patents 3118887 and 5197991.

A second preferred class of triazine UVAs is that having the formula:

in which M has its previous significance and R7 and R8 are C1-C12-alkoxy or SO3M in which M has its previous significance. Preferably halogen is chlorine.

C1-C12AIkoxy groups R7 and R8 may be, e.g., methoxy, ethoxy, n-propoxy, isopropoxy, nbutoxy, isobutoxy, tert.-butoxy, n-amyloxy, n-hexoxy, n-heptoxy, n-octoxy, isooctoxy, nnonoxy, n-decoxy, n-undecoxy or n-dodecoxy, methoxy and ethoxy being preferred.

A preferred compound of formula (2) is that having the formula:

The compounds of formula (2) are known and may be prepared e.g. by the method described in U.S.Patents 3118887 and 5197991.

A third preferred class of triazine UVAs is that having the formula:

in which M has its previous significance; n1 and n2, independently, are 0 or 1, provided that if n1 is 0, n2 is 0; R9 is optionally substituted aryl or a group having the formula:

in which Rt, is optionally substituted alkyl or optionally substituted aryl; or, when n2 is 0, Rg may also be a group having one of the formulae:

in which Rtl has its previous significance;

in which R12 is M, optionally substituted alkyl or optionally substituted aryl;

in which R12 has its previous significance;

in which R13 is hydrogen, optionally substituted alkyl or optionally substituted aryl; and Rlo is hydrogen, halogen, preferably chlorine, optionally substituted alkyl1 optionally substituted aryl,

- NH2,-N(CH2CH2OH)2,-N[CH2CH(OH)CH3]2,-NH-R12,-N(R12)2 or -OR12, in which R12 has its previous significance, or Rro is an aminoacid residue from which a hydrogen atom on the amino group has been removed.

When one or more of R10, R11, R12 and R13 is optionally substituted alkyl, preferred unsubstituted alkyl groups R10, R11, R12 and R13 are C1-C12-, especially C1-C4-alkyl groups.

The alkyl groups may be branched or unbranched and may be optionally substituted, e.g.

by halogen such as fluorine, chlorine or bromine, by Cl-C4-alkoxy such as methoxy or ethoxy1 by phenyl or carboxyl, by C1-C4-alkoxywarbonyl such as acetyl, by a mono- or di-C1 C4alkylated amino group or by -SO3M in which M has its previous significance.

When one or more of R10, R11, R12 and R13 are optionally substituted aryl, they are preferably a phenyl or naphthyl group which may be substituted by C144-alkyl, e.g. by methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec.-butyl or tert.-butyl, by C1-C4-alkoxy such as methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, sec.-butoxy or tert.-butoxy, by halogen such as fluorine, chlorine or bromine, by CrCsalkanoylamino, such as acetylamino, propionylamino or butyrylamino, by nitro, sulpho or by di-C1-C4alkylated amino.

Preferably, each of the aminoacid residues R10 is the same. Examples of preferred aminoacid residues Rio include those having the formula -NH-CH(CO2H)-R14 in which R14 is hydrogen or a group having the formula -CHR15 R16 in which R15 and R161 independently, are hydrogen or C1-C4alkyl optionally substituted by one or two substituents selected from hydroxy, thio, methylthio, amino, carboxy, sulfo, phenyl, 4-hydroxyphenyl, 3,5-diiodo4- hydroxyphenyl, -indolyl, frimidazolyl and NH=C(NH2)NH-.

Specific examples of aminoacids from which such preferred aminoacid residues Rto are derived include glycine, alanine, sarcosine, serine, cysteine, phenylalanine, tyrosine (4hydroxyphenylalanine), diiodotyrosine, tryptophan (B-indolylalanine), histidine ((for imidazolylalanine), a-aminobutyric acid, methionine, valine (a-aminoisovaleric acid), norvaline, leucine (a-aminoisocaproic acid), isoleucine (a-amino- -methylvaleric acid), norleucine (cr-amino-n-caproic acid), arginine, omithine (a,Sdiaminovaleric acid), lysine (a,- diaminocaproic acid), aspartic acid (aminosuccinic acid), glutamic acid (a-aminoglutaric acid), threonine, hydroxyglutamic acid and taurine, as well as mixtures and optical Isomers thereof. Of these aminoacids from which such preferred aminoacid residues R10 are derived, glutamic acid and aspartic acid are particularly preferred.

A further preferred example of an aminoacid from which an aminoacid residue Rto may be derived is iminodiacetic acid.

Other, less preferred examples of aminoacids from which aminoacid residues R10 may be derived include cystine, lanthionine, proline and hydroxyproline.

In each of the compounds of formula (3) it is preferred that they are used in neutral form, i.e. that M is other than hydrogen, preferably a cation formed from an alkali metal, in particular sodium, or from an amine.

In the compounds of formula (3), preferably Rg is phenyl, methylphenyl, dimethylphenyl or a group of formula:

in which R11 has its previous significance and is preferably C1-C4-alkyl, especially methyl or ethyl; and preferably R10 is phenyl, methylphenyl, dimethylphenyl,

N(CH2CH20H)2 or-N[CH2CH(OH)CH3]2.

Preferred compounds of formula (3) are those having the formula:

The compounds of formula (3) may be produced by reacting, under known reaction conditions, cyanuric chloride, successively, in any desired sequence, with each of an aminostilbenesulfonic acid, an amino compound capable of introducing a group R. and a compound capable of introducing a group Rlo, in which Rs and Rro each have their previous significance. Unsymmetrical compounds of formula (3), namely those in which n2 is zero, may be produced by the method described in GOA-2,298,422.

The starting materials are known compounds which are readily available.

Most of the compounds of formula (3) are known. Those compounds of formula (3), however, in which R9 is optionally substituted aryl and Rlo, M, n1 and n2 have their previous significance, are believed to be new compounds and, as such, form a further aspect of the present invention.

The new compounds of formula (3) may be produced from cyanuric chloride, as described above, but are preferably produced by using the appropriate intermediate selected from 2 chloro-4,6-diphenyl-1 3,5-triazine [produced according to the method of A.Ostrogovich; Chemiker Ztg. 36 (1912) 739], 2-amino-4-chloro-6-phenyl-1 ,3,5-triazine (produced according to the method described by H.K.Reimschuessel, N.T.McDevitt; J.Am.Chem.Soc.

82 (1960) 3756-3762] or the new intermediate 2-chloro-4-N-morpholino-6-phenyl-1 ,3,5- triazine. The latter new intermediate may be obtained by reacting 2,4-dichloro-6-phenyl1,3,5-triazine with morpholine under known reaction conditions.

The triazine-based ultra-violet absorption agents used as quencher compounds according to the process of the present invention are preferably used in an amount ranging from 0.5 to 50 times the amount of fluorescent whitening agent present in the substrate to be treated.

The following Examples further illustrate the present invention.

ExamDles 1 to 5 5 g of dry sulfite pulp, consisting of a 1:1 mixture of bleached beech fibres and bleached spruce fibres (Schopper-Riegler), are suspended in 150 mls of water. 5% of a calcium carbonate filler is then added to the fibre suspension, followed by 0.2% of active substance, each based on the weight of fibre, of the fluorescent whitening agent having the formula:

(as the diethanolamine salt). The mixture is then stirred at room temperature for 15 minutes.

There are then added 25 mls of a solution, in a dimethylsulfoxide/water (20:80) mixture, of one of the following quencher test compounds, to give respective pulp suspensions containing 0.2% by weight, based on the weight of pulp, of the test quencher compound:

The respective test quencher compounds are then stirred for an additional 15 minutes at room temperature in order to allow them to exert their effect.

Paper sheets are then formed from the respective suspensions (diluted to a consistency of 0.2% with water of 10 German hardness) using a Rapid-Kothen apparatus. After drying the finished paper sheet for 15 minutes, a dry paper sheet having a weight per unit area of 160 9lem2.

For the purpose of comparison, a paper sheet is produced in the same way from the basic pulp suspension containing the fluorescent whitening agent but no test quencher compound.

24 Hours after the production of the respective paper sheets, the Ganz whiteness and the fluorescence (ISO) are determined using the Spektaflash device. The Ganz method is described in detail in the Ciba-Geigy Review, 1973/1, and also in the article "Whiteness Measurement", ISCC Conference on Fluorescence and the Colorimetry of Fluorescent Materials, Williamsburg, February 1972, published in the Joumal of Color and Appearance, 1, No.5 (1972).

The results obtained are set out in the following Table.

Table

Example Test Quencher Ganz Whiteness ISO Fluorescence control none 187.4 17.8 1 101 142.0 13.8 2 102 126.8 11.9 3 103 87.5 7.4 4 104 78.5 8.7 5 105 107.5 9.5 The results in the Table indicate the significant reduction in whiteness and fluorescence of paper treated with a quencher compound according to the present invention.

ExamDle 6

4.32 g of 4,4'-diaminostilbene-2,2'-disullonic add are stirred in 200 mls of dimethylformamide and heated to 55"C. There are then added to this mixture 4.32 g of 2 chloro-4,6-diphenyl-1 ,3,5-triazine [produced according to the method of A.Ostrogokh; Chemiker Ztg. 36 (1912) 739] and 2.27 g of sodium carbonate and the resulting mixture is heated to 105-11 00C. for 28 hours. After cooling, the yellow suspension so obtained is rotated, boiled with 150 mis of a methanol/methylethylketone/water mixture, alowed to cool and then filtered. After drying in vacuum, there are obtained 5.45 g of a yellow powder of formula (106) characterized as follows: 4, 370nm/ e 54000 (DMF): 'H-NMR (DMSO-d6): 6(in ppm)= 10.42 (s, 2H, NH-), 8.75 (d, 2H, aromatic), 8.65 (d, 8H, aromatic), 8.14 (s, 2H, -CH=CH-), 7.89 (dd, 2H, aromatic), 7.71 (d, 2H, aromatic), 7.68-7.56 (m, 12H, aromatic).

Example 7

Using an analogous procedure to that described in Example 6, the compound of formula (107) is obtained and is characterized as follows: #max 370nm/ e 52900 (DMF): tH-NMR (DMSO-d6): 6(in ppm)= 10.42 (s, 2H, NH-), 8.76 (d, 2H, aromatic), 8.55 (d, 8H, aromatic), 8.14 (s, 2H, -CH=CH-), 7.85 (dd, 2H, aromatic), 7.70 (d, 2H, aromatic), 7.43 (d, 8H, aromatic), 2.45 (s, 12H, -CH3). Example 8

Using an analogous procedure to that described in Example 6, the compound of formula (108) is obtained and is characterized as follows: 4 364nm/ e 52900 (DMF): 1H-NMR (DMSOd6): b(in ppm)= 10.31 (s, 2H, NH-), 8.33 (d, 2H, aromatic), 8.08 (s, 2H, -CH=CH-), 8.02 (d, 4H, aromatic), 7.90 (dd, 2H, aromatic), 7.63 (d, 2H, aromatic), 7.21 (d, 4H, aromatic), 7.18 (s, 4H, aromatic), 2.66 (s, 12H, -CH3), 2.36 (s, 12H, -CH3).

Example 9

A) 15.82 g of 2,4-dichloro-6-phenyl-1 ,3,5-triazine are stirred at 20"C. into 200 mis of acetone and treated with 6.2 mls of morpholine and 9.4 mls of collidine. The mixture is stirred for 6 hours, made up to 1000 mls with cooled water and acidified with concentrated HCI. After stirring for 20 minutes, the suspension is filtered with suction, washed with deionised water and dried over phosphorus pentoxide. In this way, there are obtained 18.21 g of a beige powder having the formula (109A) and being characterized as follows: 1H-NMR (acetone-d6): 6(in ppm)= 8.41 (d, 2H, aromatic), 7.62 (t, 1H, aromatic), 7.52 (t, 2H, aromatic), 4.05 (t, 2H, -CH2-), 3.87 (t, 2H, -CH2-), 3.80-3.72 (m, 4H, -CH2-).

B) Using an analogous procedure to that described in Example 6, the compound of formula (109A) is reacted with 4,4'-diaminostilbene-2,2'-disulfonic acid and the compound of formula (103) is obtained and is characterized as follows: 4, 363nm/ 55557 (DMF/water): 'H-NMR (D20): & (in ppm)= 8.56 (s, 2H, aromatic), 8.27 (d, 4H, aromatic), 7.84 (s, 2H, -CH=CH-), 7.73 (d, 2H, aromatic), 7.63 (t, 2H, aromatic), 7.59-7.48 (m, 6H, aromatic), 3.89 (s, 8H, -OH2-), 3.80 (s, 8H, -CH2-).

Example 10

Using an analogous procedure to that described in Example 6, 2-amino4chlorn-6-phenyl- 1,3,5-triazine [produced according to the method described by H.K.Reimschuessel, N.T.McDevitt; J.Am.Chem.Soc. 82 (1960) 3756-3762] is reacted with 4,4'-diaminostilbene 2,2'-disulfonic acid and the compound of formula (110) is obtained and is characterized as follows: #max 360nm/# 45366 (DMFhvater): rH-NMR (MeOH-d4): 8(in ppm)= 8.65 (s, 2H, aromatic), 8.47 (d, 4H, aromatic), 8.17 (s, 2H, -CH=CH-), 7.96 (d, 2H, aromatic), 7.85 (dd, 2H, aromatic), 7.63-7.52 (m, 6H, aromatic).

Example 11

1.2 g of 1 aminoacetophenone are dissoived in 30 ml of methylcellosolve. To this solution are then added 3.3 g of the compound (91% purity) having the formula:

The reaction mixture is heated to 130"C. in an oilbath and held at this temperature for 4 hours. After a short time, the free acid version of the salt compound (111) crystallises out.

After filtration with suction, the filtercake, dissolved in methanol, is converted into the disodium salt of formula (111) using sodium methylate. After filtration with suction, washing with water and drying1 there are obtained 4.0 g (91% theory) of the di-sodium salt of formula (111).

Elemental analysis of the compound having the formula (111) and having the empirical formula C48H38Nr2Na208S2.11.0 H20 gives: Req.% C 47.29; H 4.96; N 13.78; S 5.26; H2O 16.24.

Found % C 47.05; H 4.96; N 13.87; S 5.28; H2O 15.99.

Example 12

18.81 g of cyanuric chloride (98% purity) are dissolved in 95 ml of acetone and poured on to 100 g of a mixture of ice and water. Over 30 minutes, a solution of 18.5 g of of diaminostilbene-di-sulfonic acid (100% purity) is added, dropwise, into 320 g of a mixture of ice and water at a temperature in the range of from -5 C. to 0 C. Finally, over 15 minutes, 50 ml of a 1 molar soda solution are added, dropwise, at this temperature, and the whole is stirred for a further 1 hour. 13.5 g of 4-aminoacetophenone are added and the mixture is heated to 50"C., over 90 minutes. During this procedure, the pH of the reaction mixture is held at 78 by the addition of sodium carbonate. In order to complete the reaction, the acetone is distilled off until the temperature of the reaction mixture has reached 66"C. The precipitated deposit is filtered warm with suction, washed with dilute aqueous sodium chloride (2%) and then with 300 ml of cold water. After drying, there remain 44.8 g (88% theory) of the compound of formula (101).

Elemental analysis of the compound having the formula (101) and having the empirical formula C3sH28N1008C12S2Na2 6.0 H20 gives: Req.% C 42.57; H 3.77; N 13.79.

Found % C 42.59; H 3.85; N 13.74.

Example 13

5 g of the compound of formula (101) obtained in Example 12 are suspended in 100 ml of water. 1.3 g of taurine are added and the reaction mixture is heated to 90"C. and the pH is held at 9-10 using sodium carbonate. The reactants are allowed to further react at this pH and temperature for 15 hours. Finally, the reaction mixture is concentrated and the compound (113) is precipitated with acetone. After filtration with suction, washing with acetone and drying, there remain 5.9 g (81% theory) of the compound (113).

Elemental analysis of the compound having the formula (113) and having the empirical formula C40H3sN,2Na4014S4. 0.66 NaCI. 16.5 H20 gives: Req.% C 32.8; H 4.74; N 11.47; S 8.75; Cli 1.60; Na 7.32.

Found % C 32.7; H 4.7; N 11.5; S 9.1; Cl 1.6; Na 7.4.

Example 14

Using an analogous procedure to that described in Example 13, compound (114) is produced by reacting the compound (101) with 0.9 g of sarcosine instead of taurine. The reaction is complete after 6 hours and the yield of the compound (114) is 93% of theory.

Elemental analysis of the compound having the formula (114) and having the empirical formula C92H3SN12Na9012S2 15 H20 gives: Req.% C 38.02; H 5.01; N 12.66.

Found % C 38.10; H 4.87; N 12.65.

Example 15

Using an analogous procedure to that described in Example 13, compound (115) is produced by reacting the compound (101) with N-methyl-ethanolamine instead of taurine.

The reaction is complete after 6.5 hours and the yield of the compound (115) is 81% of theory.

The material analyzed was partly present as the N- methyl-ethanolamine salt.

Elemental analysis of the compound having the formula (115) and having the empirical formula C42H42N12Na2O10S2. 0.6 N- methyl-ethanolamine. 5 H2O gives: Req.% C 47.0; H 5.02; N 15.78; S 5.73.

Found % C 46.75; H 4.92; N 15.46; S 5.71.

Example 16

10 g of the compound of formula (101) are reacted with 5.8 g of L-glutamic acid in a 6:9 by weight mixture of water and methylcellosolve at 120"C. in an oil bath, the pH being held at 8-9 by the addition of sodium carbonate. After 6 hours, the reaction is complete. The reaction mixture is dropped into acetone acidified with HCI, whereupon the compound of formula (116) precipitates out as the free acid. After filtration with suction and washing with acetone-water, the filtercake is converted into the corresponding hexa-sodium salt by the addition of the calculated amount of aqueous sodium hydroxide, and evaporation to dryness. The yield is 90% of theory.

Elemental analysis of the compound having the formula (116) and having the empirical formula C46HN12Na6O10S2. 0.3 NaCI. 17 H2O gives: Req.% C 35.9; H 4.71; N 10.92; S 4.16.

Found % C 36.0; H 4.7; N 10.9; S 4.1.

Example 17

The compound of formula (117) is obtained in a yield of 87% of theory using the procedure described in Example 16, except that the L-glutamic acid is replaced by iminodiacetic acid.

Elemental analysis of the compound having the formula (117) and having the empirical formula C44H34N,2Na6016S2. 0.8 NaCI. 15 H20 gives: Req.% C 35.1; H 4.28; N 11.16; S 4.26.

Found % C 35.0; H 4.3; N 11.2; S 4.4.

Examples 18to26 The activity as quenchers of various triazine-based UVAs used according to the present invention is investigated as follows. The fibre suspension used is an industrially produced suspension consisting predominantly of eucalyptus pulp taken from the pulp circulating in a paper machine. Since the test fibre suspension contains only a minor amount of fluorescent whitening agent, there is added to the fibre suspension 0.1% by weight of active substance of a commercial paper fluorescent whitening agent based on a substituted tetrasulfostilbene. After a further 24 hours has elapsed, to enable the added fluorescent whitening agent to exert its effect, the test quencher compound is added1 at a level of 0.8% by weight of active substance, to the fibre suspension in a consistency of 1 % by weight.

After 15 minutes exhaustion time, a paper sheet is formed using the Rapid Kothen system and the sheet is dried. The dried sheet is then exposed to xenon light (Spektraflash SF 500) and the fluorescence of the sheet is determined, firstly using a UV barrier filter (420 nm) and then without the use of the UV barrier filter. The difference between the two measurements at 440 nm is designated as the fluorescence (F 440).

The test quencher compounds have the formula:

The test results obt

Table

Example R F440 control (no quencher) 31 18 NH2 (compound 104) 9 19 anilino (NH-phenyl) (compound 111) 10 20 NH-(CH2)2OCH3 9 21 O-(CH2)2-CH3 18 22 NH-(CH2)s-COOH 12 23 N(CH3)(CH2COOH) (compound 114) 11 24 NH-(CH2)2-SO3H (compound 113) 12 25 N(CH3)-(CH2)rOH (compound 115) 10 26 N(2Hs)-(CH2)2-OH 11 Since the higher the value of F 440, the higher the fluorescence, it will be noted that the test compounds significantly reduce (quench) the fluorescence, relative to the control experiment.

Claims

1. A process for the inhibition (quenching) of the effect of an anionic fluorescent whitening agents on a substrate, comprising treating the substrate with a triazine UVA compound.

2. A process according to claim 1 in which the triazine UVA compound is a compound having the formula:

in which at least one of R1, R2 and R3 is a radical of formula:

in which R4, R5 and R6, independently, are hydrogen; C1-Cl2alkoxy; hydroxy; -O-CH2-CO-NH-CH2OH; SO3M in which M is hydrogen, sodium, potassium, ammonium, mono-, di-, tri- or tetra-C1-C4alkylammonium, mono-, di- or tri-C,-C4hydroxyalkylammonium or ammonium that is di- or tri-substituted by a mixture of C1-C4alkyl and C1-C4hydroxyalkyl groups; or

in which n is an integer from 2 to 6; Y1 and V21 independently, are C1-C4alkyl optionally substituted by halogen, cyano, hydroxy or C1- C4alkoxy or V1 and Y2, together with the nitrogen atom to which they are each attached, form a 5-7 membered heterocyclic ring; Y3 is hydrogen, C3-C4alkenyl or C,-C4alkyl optionally substituted by cyano, hydroxy or C1-C4alkoxy or V1, Y2 and V3, together with the nitrogen atom to which they are each attached, form a pyridine or picoline ring; and X1 is a colourless anion; and the remaining substituent(s) R1, R2 and R3 are, independently, halogen, C1-Ct2alkoxy or phenyl, the phenyl substituent being optionally substituted by one or more of hydroxy, Ci- Ct2-alkoxy, -O-CH2-CO-NH-CH2OH, SO3M in which M has its previous significance.

3. A process according to claim 2 in which n is 2 or 3.

4. A process according to claim 3 in which V1 and V21 together with the nitrogen atom to which they are each attached, form a morpholine, pyrrolidine, piperidine or hexamethyleneimine ring.

5. A process according to any of claims 2 to 4 in which X1 is CH30SO3- or C2H5OSO3.

6. A process according to any of claims 2 to 4 in which the remaining substituent(s) R11 R2 and R3 are, independently, chlorine.

7. A process according to claim 2 in which the compound of formula (1) has the formula:

8. A process according to claim 1 in which the the triazine UVA compound is a compound having the formula:

halogen N1N S7 0 0 (2) NH-O1-O1-NHNH N NH-SO2OH2OH2-O-SO3M in which M is as defined in claim 2 and R7 and R8 are C1-C12-alkoxy or SO3M in which M is as defined in claim 2.

9. A process according to claim 8 in which halogen is chlorine.

10. A process according to claim 8 or 9 in which the compound of formula (2) has the formula:

11. A process according to claim 1 in which the the triazine UVA compound is a compound having the formula:

in which M is as defined in claim 2; n1 and n2, independently, are 0 or 1, provided that if n1 is 0, n2 is 0; Rg is optionally substituted aryl or a group having the formula:

in which R11 is optionally substituted alkyl or optionally substituted aryl; or, when n2 is 0, Rg may also be a group having one of the formulae:

in which R11 is optionally substituted alkyl or optionally substituted aryl;

in which R12 is M, optionally substituted alkyl or optionally substituted aryl;

in which R12 has its previous significance;

in which R13 is hydrogen, optionally substituted alkyl or optionally substituted aryl; and Rio is hydrogen, halogen, optionally substituted alkyl, optionally substituted aryl,

- NH2, -N(CH2CH2OH)2, -N[CH2CH(OH)CH3]2, -NH-R121 -N(R12)2 or -OR,2, in which R12 has its previous significance, or Rio is an aminoacid residue from which a hydrogen atom on the amino group has been removed.

12. A process according to claim 11 in which R10 is an aminoacid residue having the formula -NH-CH(CO2H)-R14 in which R14 is hydrogen or a group having the formula -CHR15R16 in which R15 and R16, independently, are hydrogen or C1C4alkyl optionally substituted by one or two substituents selected from hydroxy, thio, methylthio, amino, carboxy, sulfo, phenyl, 4hydroxyphenyl, 3,5-diiodo-4-hydroxyphenyl, findoiyl, fimidazolyl and NH=C(NH2)NH-.

13. A process according to claim 11 in which R10 is an aminoacid residue derived from glycine, alanine, sarcosine, serine, cysteine, phenylalanine, tyrosine (4hydroxyphenylalanine), diiodotyrosine, tryptophan ( > indolylalanine), histidine (( > imidazolylalanine), a-aminobutyric acid, methionine, valine (a-aminoisovaleric acid), norvaline, leucine (a-aminoisocaproic acid), isoleucine (α-amino-ss-methylvaleric acid), norleucine (a-amino-n caproic acid), arginine, omithine ( ,Wiaminovaleric acid), lysine (a,e- diaminocaproic acid), aspartic acid (aminosuccinic acid), glutamic acid (a-aminoglutaric acid), threonine, hydroxyglutamic acid or taurine, or a mixture or optical isomer thereof. Of these aminoacids from which such preferred aminoacid residues R10 are derived, glutamic acid and aspartic acid are particularly preferred.

14. A process according to claim 11 in which R10 is an aminoacid residue derived from iminodiacetic acid.

15. A process according to claim 11 in which R10 is an aminoacid residue derived from taurine, sarcosine, glutamic acid or iminodiacetic acid.

16. A process according to claim 11 in which Rro is chloro, amino, phenyl, methylphenyl, dimethylphenyl, morpholino or an aminoacid residue from which a hydrogen atom on the amino group has been removed.

17. A process according to claim 11 in which Rg is phenyl, methylphenyl, dimethylphenyl or a group of formula:

in which R11 is defined in daim 11; and Rio is phenyl, methylphenyl, dimethylphenyl,

-N[CH2CH(OH)CH312 or an aminoacid residue from which a hydrogen atom on the amino group has been removed.

18. A process according to claim 17 in which R11 is C1-C4-alkyl.

19. A process according to claim 17 in which R11 is methyl or ethyl.

20. A process according to claim 11 in which the compound of formula (3) has the formula:

21. A process according to any of the preceding daims in which the triazine-based ultra violet absorption agent used as a quencher compound is used in an amount ranging from 0.5 to 50 times the amount of fluorescent whitening agent present in the substrate to be treated.

22. A substrate when treated according to a process claimed in any of the preceding claims.

23. A compound having the formula:

in which M is as defined in claim 2; n1 and n2, independently, are 0 or 1, provided that if nl is 0, n2 is 0; Rg is optionally substituted aryl; and R10 is hydrogen, halogen, optionally substituted alkyl, optionally substituted aryl,

in which R13 is as defined in claim 11.

24. A compound according to claim 23 in which n1 and n2 are each 1; Rg is phenyl, methylphenyl or dimethylphenyl; and Rlo is chlorine, amino, phenyl, methylphenyl or dimethylphenyl,

-N(R13)2 or -OR13, in which R13 is as defined in claim 11.

25. The compound having the formula:

26. The compound having the formula:

27. The compound having the formula:

28. The compound having the formula:

29. The compound having the formula:

30. The compound having the formula:

31. The compound having the formula: