Fluorescent whitening agents and mixtures thereof

Abstract

Novel fluorescent whitening agents, compositions or mixtures thereof with known fluorescent whitening agents, their preparation, and their use. The novel fluorescent whitening agents (FWAs) contain three structural subunits derived from 4,4-diamino-2,2-stilbenedisulfonic acid. The novel compounds and their mixtures with known FWAs show very good effectiveness as fluorescent whitening agents for cellulosic materials, in particular for paper.

Claims

1. A compound having the following formula (1): ##STR00013## wherein n is 0, 1, or 2; and wherein R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, R.sub.6, R.sub.7 and R.sub.8 independently of each other are H, linear or branched C.sub.1-C.sub.4 alkyl, linear or branched C.sub.2-C.sub.4 hydroxyalkyl, linear or branched C.sub.1-C.sub.4 alkoxyalkyl, linear or branched C.sub.2-C.sub.4 cyanoalkyl, phenyl substituted with SO.sub.3.sup., (CH.sub.2).sub.iSO.sub.3.sup., (CH.sub.2).sub.i-phenyl, (CH.sub.2).sub.kCOOM, (CH.sub.2).sub.kCOOR.sub.9, (CH.sub.2).sub.kCONH.sub.2, (CH.sub.2).sub.kOR.sub.9, wherein i is an integer from 1 to 3, k is an integer from 1 to 4, and R.sub.9 is linear or branched C.sub.1-C.sub.3 alkyl; or R.sub.1 and R.sub.2, or R.sub.3 and R.sub.4, or R.sub.5 and R.sub.6, or R.sub.7 and R.sub.8 independently of each other together with the nitrogen atom form a morpholine, a piperidine or a pyrrolidine ring; and wherein M represents the corresponding cationic charge equivalent selected from the cations H.sup.+, alkali metal cation, Ca.sup.2+, Mg.sup.2+, ammonium, C.sub.1-C.sub.4 tetraalkyl ammonium, ammonium which is mono-, di-, tri- or tetra-substituted by C.sub.2-C.sub.3 hydroxyalkyl radicals, and NH(R.sub.10).sub.o(R.sub.11).sub.p.sup.+ with R.sub.10 being C.sub.1-C.sub.4 alkyl and R.sub.11 being C.sub.2-C.sub.3 hydroxyalkyl, wherein both o and p are an integer of 1 or 2, and op, alkyl is linear or branched; and mixtures of said cations.

2. The compound of claim 1, wherein n is an integer of 1 or 2; the substituent NR.sub.1R.sub.2 is identical to NR.sub.7R.sub.8, the substituent NR.sub.3R.sub.4 is identical to NR.sub.5R.sub.6; and M is selected from the cations H.sup.+, Na.sup.+, Li.sup.+, K.sup.+, ammonium, ammonium which is mono-, di-, tri- or tetra-substituted by C.sub.2-C.sub.3 hydroxyalkyl radicals, or mixtures of said cations.

3. The compound of claim 1, wherein n is an integer of 1 or 2; the substituents R.sub.1 to R.sub.8 are selected from H, linear or branched C.sub.1-C.sub.4 alkyl, linear or branched C.sub.2-C.sub.4 hydroxyalkyl, (CH.sub.2).sub.iSO.sub.3.sup.+, wherein i is an integer from 1 to 3, and phenyl substituted with SO.sub.3.sup.; and M is selected from the cations H.sup.+, Na.sup.+, Li.sup.+, K.sup.+, ammonium, ammonium which is mono-, di-, tri- or tetra-substituted by C.sub.2-C.sub.3 hydroxyalkyl radicals, or mixtures of said cations.

4. The compounds of claim 1, wherein R.sub.1 to R.sub.8 independently of each other are selected from H, linear or branched C.sub.1-C.sub.3 alkyl, linear or branched C.sub.2-C.sub.3 hydroxyalkyl, phenyl substituted with SO.sub.3.sup., and CH.sub.2CH.sub.2SO.sub.3.sup..

5. A process for preparing a compound of formula (1) according to claim 1, wherein the process comprises the following steps: in a first reaction step, 2,4,6-trichloro-1,3,5-triazine (cyanuric chloride) is reacted with an aromatic amine of the formula (2) and a compound of formula (3) according to the following reaction scheme, to obtain a mixture of the compounds of formula (5) and formula (6): ##STR00014## wherein n is 0, 1, or 2; and wherein M represents the corresponding cationic charge equivalent selected from the cations H.sup.+, alkali metal cation, Ca.sup.2+, Mg.sup.2+, ammonium, C.sub.1-C.sub.4 tetraalkyl ammonium, ammonium which is mono-, di-, tri- or tetra-substituted by C.sub.2-C.sub.3 hydroxyalkyl radicals, and NH(R.sub.10).sub.o(R.sub.11).sub.p.sup.+ with R.sub.10 being C.sub.1-C.sub.4 alkyl and R.sub.11 being C.sub.2-C.sub.3 hydroxyalkyl, wherein both o and p are an integer of 1 or 2, and op, alkyl is linear or branched; and mixtures of said cations; in a second reaction step, the obtained mixture of the compounds of formulae (5) and (6) is reacted with a compound of formula (3) according to the following reaction scheme, to obtain a mixture of the compounds of formula (7) and formula (8): ##STR00015## wherein n is 0, 1 or 2; and M represents the corresponding cationic charge equivalent selected from the cations H.sup.+, alkali metal cation, Ca.sup.2+, Mg.sup.2+, ammonium, C.sub.1-C.sub.4 tetraalkyl ammonium, ammonium which is mono-, di-, tri- or tetra-sibstituted by C.sub.2-C.sub.3, hydroxyalkyl radicals, and NH(R.sub.10).sub.o(R.sub.11).sub.p.sup.+ with R.sub.10 being C.sub.1-C.sub.4alkyl and R.sub.11 being C.sub.2-C.sub.3 hydroxyalkyl, wherein both o and p are an integer of 1 or 2, and op, alkyl is linear or branched, and mixtures of said cations; in a third reaction step the obtained mixture of the compounds of formulae (7) and (8) is reacted with at least one amine selected from ammonia, primary and secondary amines, wherein the organic substituents of the primary and secondary amine are selected from linear or branched C.sub.1-C.sub.4 alkyl, linear or branched C.sub.2-C.sub.4 hydroxyalkyl, linear or branched C.sub.1-C.sub.4 alkoxyalkyl, linear or branched C.sub.2-C.sub.4 cyanoalkyl, phenyl substituted with SO.sub.3.sup., (CH.sub.2).sub.iSO.sub.3.sup., (CH.sub.2).sub.i-phenyl, (CH.sub.2).sub.kCOOM, (CH.sub.2).sub.kCOOR.sub.9, (CH.sub.2).sub.kCONH.sub.2, (CH.sub.2).sub.kOR.sub.9, wherein i is an integer from 1 to 3, k is an integer from 1 to 4, and R.sub.9 is linear or branched C.sub.1-C.sub.3 alkyl; or the substituents of the secondary amine together with the nitrogen atom form a morpholine, a piperidine or a pyrrolidine ring, ##STR00016##

6. The process of claim 5, wherein, in the first reaction step, the molar ratio of cyanuric chloride to the compound of formula (2) to the compound of formula (3) is in the range of from 1:0.65 to 1.095:0.0025 to 0.15.

7. The process of claim 5, wherein in the first reaction step, the molar ratio of cyanuric chloride to the compound of formula (2) to the compound of formula (3) is in the range of from 1:0.70 to 0.80:0.10 to 0.15.

8. The process of claim 5, wherein in the first reaction step, the molar ratio of cyanuric chloride to the compound of formula (2) to the compound of formula (3) is in the range of from 1:0.80 to 1:08:0.01 to 0.075.

9. The process of claim 5, wherein, in the second reaction step, the molar ratio of cyanuric chloride to the compound of formula (3) is in the range of from 1:0.425 to 0.525.

10. The process of claim 5, wherein in the second reaction step, the molar ratio of cyanuric chloride to the compound of formula (3) is in the range of from 1:0.425 to 0.500.

11. The process of claim 5, wherein, in the third reaction step, the molar ratio of cyanuric chloride to the total amount of amines is in the range of from 1:1.00 to 1.50.

12. The process of claim 5, wherein in the third reaction step, the molar ratio of cyanuric chloride to the total amount of amines is in the range of from 1:1.00 to 1.25.

13. The process of claim 5, wherein a compound (1a) is prepared, wherein the process comprises the first and second reaction steps of the preparation of the compound of formula (1), and wherein in the third reaction step, the obtained mixture of the compounds of formulae (7) and (8) is reacted with an amine of the formula NHR.sub.XR.sub.y, to obtain a mixture of the compound of formula (1a) and the compound of formula (10): ##STR00017## wherein n is 0, 1, or 2; and M represents the corresponding cationic charge equivalent selected from the cations H.sup.+, alkali metal cation, Ca.sup.2+, Mg.sup.2+, ammonium, C.sub.1-C.sub.4 tetraalkyl ammonium, ammonium which is mono-, di-, tri- or tetra-substituted by C.sub.2-C.sub.3 hydroxyalkyl radicals, and NH(R.sub.10).sub.o(R.sub.11).sub.p.sup.+ with R.sub.10 being C.sub.1-C.sub.4 alkyl and R.sub.11 being C.sub.2-C.sub.3 hydroxyalkyl, wherein both o and p are an integer of 1 or 2, and op, alkyl is linear or branched; and mixtures of said cations, and wherein R.sub.x and R.sub.y independently of each other are H, linear or branched C.sub.1-C.sub.4 alkyl, linear or branched C.sub.2-C.sub.4 hydroxyalkyl, linear or branched C.sub.1-C.sub.4 alkoxyalkyl, linear or branched C.sub.2-C.sub.4 cyanoalkyl, or (CH.sub.2).sub.iSO.sub.3.sup., (CH.sub.2).sub.i-phenyl, (CH.sub.2).sub.kCOOM, (CH.sub.2).sub.kCOOR.sub.9, (CH.sub.2).sub.kCONH.sub.2, (CH.sub.2).sub.kOR.sub.9, wherein i is an integer from 1 to 3 and wherein k is an integer from 1 to 4, R.sub.9 is linear or branched C.sub.1-C.sub.3 alkyl, or R.sub.x and R.sub.y independently of each other together with the nitrogen atom form a morpholine, a piperidine or a pyrrolidine ring.

14. A composition comprising at least one compound of formula (1) ##STR00018## wherein n is 0, 1, or 2; and wherein R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, R.sub.6, R.sub.7 and R.sub.8 independently of each other are H, linear or branched C.sub.1-C.sub.4 alkyl, linear or branched C.sub.2-C.sub.4 hydroxyalkyl, linear or branched C.sub.1-C.sub.4 alkoxyalkyl, linear or branched C.sub.2-C.sub.4 cyanoalkyl, phenyl substituted with SO.sub.3.sup., (CH.sub.2).sub.iSO.sub.3.sup., (CH.sub.2).sub.i-phenyl, (CH.sub.2).sub.kCOOM, (CH.sub.2).sub.kCOOR.sub.9, (CH.sub.2).sub.kCONH.sub.2, (CH.sub.2).sub.kOR.sub.9, wherein i is an integer from 1 to 3, k is an integer from 1 to 4, and R.sub.9 is linear or branched C.sub.1-C.sub.3 alkyl; or R.sub.1 and R.sub.2, or R.sub.3 and R.sub.4, or R.sub.5 and R.sub.6, or R.sub.7 and R.sub.8 independently of each other together with the nitrogen atom form a morpholine, a piperidine or a pyrrolidine ring; and wherein M represents the corresponding cationic charge equivalent selected from the cations H.sup.+, alkali metal cation, Ca.sup.2+, Mg.sup.2+, ammonium, C.sub.1-C.sub.4 tetraalkyl ammonium, ammonium which is mono-, di-, tri- or tetra-substituted by C.sub.2-C.sub.3 hydroxyalkyl radicals, and NH(R.sub.10).sub.o(R.sub.11).sub.p.sup.+ with R.sub.10 being C.sub.1-C.sub.4 alkyl and R.sub.11 being C.sub.2-C.sub.3 hydroxyalkyl, wherein both o and p are an integer of 1 or 2, and op, alkyl is linear or branched; and mixtures of said cations: and at least one further fluorescent whitening agent (FWA) selected from the compound of formula (4) and the compound of formula (9): ##STR00019## wherein n=0, 1, or 2, R.sub.x and R.sub.y independently of each other are H, C.sub.1-C.sub.4 alkyl, C.sub.2-C.sub.4 hydroxyalkyl, C.sub.1-C.sub.4 alkoxyalkyl, C.sub.2-C.sub.4 cyanoalkyl, wherein the alkyl residue is linear or branched, or (CH.sub.2).sub.iSO.sub.3.sup., (CH.sub.2).sub.i-phenyl, (CH.sub.2).sub.kCOOM.sub.1, (CH.sub.2).sub.kCOOR.sub.9, (CH.sub.2).sub.kCONH.sub.2, (CH.sub.2).sub.kOR.sub.9, wherein i is an integer from 1 to 3 and wherein k is an integer from 1 to 4, R.sub.9 is linear or branched C.sub.1-C.sub.3 alkyl, or R.sub.x and R.sub.y independently of each other together with the nitrogen atom form a morpholine, a piperidine or a pyrrolidine ring; and wherein M.sub.1 represents the corresponding cationic charge equivalent selected from the cations H.sup.+, alkali metal cation, Ca.sup.2+, ammonium, C.sub.1-C.sub.4 tetraalkyl ammonium, ammonium which is mono-, di-, tri- or tetra-substituted by C.sub.2-C.sub.3 hydroxyalkyl radicals, and NH(R.sub.10).sub.o(R.sub.11).sub.p.sup.+ with R.sub.10 being C.sub.1-C.sub.4 alkyl and R.sub.11 being C.sub.2-C.sub.3 hydroxyalkyl, wherein both o and p are an integer of 1 or 2 and op, and alkyl is linear or branched; and mixtures of said cations.

15. The composition of claim 14, wherein the compound of formula (1) is the compound of formula (1a): ##STR00020## wherein n is 0, 1, or 2; and M represents the corresponding cationic charge equivalent selected from the cations H.sup.+, alkali metal cation, Ca.sup.2+, Mg.sup.2+, ammonium, C.sub.1-C.sub.4 tetraalkyl ammonium, ammonium which is mono-, di-, tri- or tetra-substituted by C.sub.2-C.sub.3 hydroxyalkyl radicals, and NH(R.sub.10).sub.o(R.sub.11).sub.p.sup.+ with R.sub.10 being C.sub.1-C.sub.4 alkyl and R.sub.11 being C.sub.2-C.sub.3 hydroxyalkyl, wherein both o and p are an integer of 1 or 2 and op alkyl is linear or branched; and mixtures of said cations, and wherein R.sub.x and R.sub.y independently of each other are H, linear or branched C.sub.1-C.sub.4 alkyl, linear or branched C.sub.2-C.sub.4 hydroxyalkyl, linear or branched C.sub.1-C.sub.4 alkoxyalkyl, linear or branched C.sub.2-C.sub.4 cyanoalkyl, or (CH.sub.2).sub.iSO.sub.3.sup., (CH.sub.2).sub.i-phenyl, (CH.sub.2).sub.kCOOM.sub.1, (CH.sub.2).sub.kCOOR.sub.9, (CH.sub.2).sub.kCONH.sub.2, (CH.sub.2).sub.kOR.sub.9, wherein i is an integer from 1 to 3 and wherein k is an integer from 1 to 4, R.sub.9 is linear or branched C.sub.1-C.sub.3 alkyl, or R.sub.x and R.sub.y independently of each other together with the nitrogen atom form a morpholine, a piperidine or a pyrrolidine ring.

16. The composition of claim 14, wherein the compound of formula (1) is present in an amount of 1 to 90 weight-%, and the at least one further fluorescent whitening agent (FWA) is present in an amount of 10 to 99 weight %, in each case based on the total amount of the compounds of formula (1) and the further fluorescent whitening agent (FWA).

17. A coating color comprising at least one white pigment; at least one binder; and at least one compound of formula (1): ##STR00021## wherein n is 0, 1, or 2; and wherein R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, R.sub.6, R.sub.7 and R.sub.8 independently of each other are H, linear or branched C.sub.1-C.sub.4 alkyl, linear or branched C.sub.2-C.sub.4 hydroxyalkyl, linear or branched C.sub.1-C.sub.4 alkoxyalkyl, linear or branched C.sub.2-C.sub.4 cyanoalkyl, phenyl substituted with SO.sub.3.sup., (CH.sub.2).sub.iSO.sub.3.sup., (CH.sub.2).sub.i-phenyl, (CH.sub.2).sub.kCOOM, (CH.sub.2).sub.kCOOR.sub.9, (CH.sub.2).sub.kCONH.sub.2, (CH.sub.2).sub.kOR.sub.9, wherein i is an integer from 1 to 3, k is an integer from 1 to 4, and R.sub.9 is linear or branched C.sub.1-C.sub.3 alkyl; or R.sub.1 and R.sub.2, or R.sub.3 and R.sub.4, or R.sub.5 and R.sub.6, or R.sub.7 and R.sub.8 independently of each other together with the nitrogen atom form a morpholine, a piperidine or a pyrrolidine ring; and wherein M represents the corresponding cationic charge equivalent selected from the cations H.sup.+, alkali metal cation, Ca.sup.2+, Mg.sup.2+, ammonium, C.sub.1-C.sub.4 tetraalkyl ammonium, ammonium which is mono-, di-, tri- or tetra-substituted by C.sub.2-C.sub.3 hydroxyalkyl radicals, and NH(R.sub.10).sub.o(R.sub.11).sub.p.sup.+ with R.sub.10 being C.sub.1-C.sub.4 alkyl and R.sub.11 being C.sub.2-C.sub.3 hydroxyalkyl, wherein both o and p are an integer of 1 or 2, and op, alkyl is linear or branched; and mixtures of said cations, or a composition comprising the compound of formula (1) and at least one further fluorescent whitening agent (FWA) selected from the compound of formula (4) and the compound of formula (9): ##STR00022## wherein n=0, 1, or 2, R.sub.x and R.sub.y independently of each other are H, C.sub.1-C.sub.4 alkyl, C.sub.2-C.sub.4 hydroxyalkyl, C.sub.1-C.sub.4 alkoxyalkyl, C.sub.2-C.sub.4 cyanoalkyl, wherein the alkyl residue is linear or branched, or (CH.sub.2).sub.iSO.sub.3.sup., (CH.sub.2).sub.i-phenyl, (CH.sub.2).sub.kCOOM.sub.1, (CH.sub.2).sub.kCOOR.sub.9, (CH.sub.2).sub.kCONH.sub.2, (CH.sub.2).sub.kOR.sub.9, wherein i is an integer from 1 to 3 and wherein k is an integer from 1 to 4, R.sub.9 is linear or branched C.sub.1-C.sub.3 alkyl, or R.sub.x and R.sub.y independently of each other together with the nitrogen atom form a morpholine, a piperidine or a pyrrolidine ring; and wherein M.sub.1 represents the corresponding cationic charge equivalent selected from the cations H.sup.+, alkali metal cation, Ca.sup.2+, ammonium, C.sub.1-C.sub.4 tetraalkyl ammonium, ammonium which is mono-, di-, tri- or tetra-substituted by C.sub.2-C.sub.3 hydroxyalkyl radicals, and NH(R.sub.10).sub.o(R.sub.11).sub.p.sup.+ with R.sub.10 being C.sub.1-C.sub.4 alkyl and R.sub.11 being C.sub.2-C.sub.3 hydroxyalkyl, wherein both o and p are an integer of 1 or 2 and op, and alkyl is linear or branched; and mixtures of said cations.

18. The coating color of claim 17, wherein said composition comprises the compound of formula (1a): ##STR00023## wherein n is 0, 1, or 2; and M represents the corresponding cationic charge equivalent selected from the cations H.sup.+, alkali metal cation, Ca.sup.2+, Mg.sup.2+, ammonium, C.sub.1-C.sub.4 tetraalkyl ammonium, ammonium which is mono-, di-, tri- or tetra-substituted by C.sub.2-C.sub.3 hydroxyalkyl radicals, and NH(R.sub.10).sub.o(R.sub.11).sub.p.sup.+ with R.sub.being C.sub.1-C.sub.4 alkyl and R.sub.11 being C.sub.2-C.sub.3 hydroxyalkyl, wherein both o and p are an integer of 1 or 2, and op, alkyl is linear or branched; and mixtures of said cations, and wherein R.sub.x and R.sub.y independently of each other are H, linear or branched C.sub.1-C.sub.4 alkyl, linear or branched C.sub.2-C.sub.4 hydroxyalkyl, linear or branched C.sub.1-C.sub.4 alkoxyalkyl, linear or branched C.sub.2-C.sub.4 cyanoalkyl, or (CH.sub.2).sub.iSO.sub.3.sup., (CH.sub.2).sub.i-phenyl, (CH.sub.2).sub.kCOOM, (CH.sub.2).sub.kCOOR.sub.9, (CH.sub.2).sub.kCONH.sub.2, (CH.sub.2).sub.kOR.sub.9, wherein i is an integer from 1 to 3 and wherein k is an integer from 1 to 4, R.sub.9 is linear or branched C.sub.1-C.sub.3 alkyl, or R.sub.x and R.sub.y independently of each other together with the nitrogen atom form a morpholine, a piperidine or a pyrrolidine ring.

19. A size press or film press liquor comprising: at least one sizing agent; and at least one compound of formula (1): ##STR00024## wherein n is 0, 1, or 2; and wherein R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, R.sub.6, R.sub.7 and R.sub.8 independently of each other are H, linear or branched C.sub.1-C.sub.4 alkyl, linear or branched C.sub.2-C.sub.4 hydroxyalkyl, linear or branched C.sub.1-C.sub.4 alkoxyalkyl, linear or branched C.sub.2-C.sub.4 cyanoalkyl, phenyl substituted with SO.sub.3.sup., (CH.sub.2).sub.iSO.sub.3.sup., (CH.sub.2).sub.i-phenyl, (CH.sub.2).sub.kCOOM, (CH.sub.2).sub.kCOOR.sub.9, (CH.sub.2).sub.kCONH.sub.2, (CH.sub.2).sub.kOR.sub.9, wherein i is an integer from 1 to 3, k is an integer from 1 to 4, and R.sub.9 is linear or branched C.sub.1-C.sub.3 alkyl; or R.sub.1 and R.sub.2, or R.sub.3 and R.sub.4, or R.sub.5 and R.sub.6, or R.sub.7 and R.sub.8 independently of each other together with the nitrogen atom form a morpholine, a piperidine or a pyrrolidine ring; and wherein M represents the corresponding cationic charge equivalent selected from the cations H.sup.+, alkali metal cation, Ca.sup.2+, Mg.sup.2+, ammonium, C.sub.1-C.sub.4 tetraalkyl ammonium, ammonium which is mono-, di-, tri- or tetra-substituted by C.sub.2-C.sub.3 hydroxyalkyl radicals, and NH(R.sub.10).sub.o(R.sub.11).sub.p.sup.+ with R.sub.10 being C.sub.1-C.sub.4 alkyl and R.sub.11 being C.sub.2-C.sub.3 hydroxyalkyl, wherein both o and p are an integer of 1 or 2, and op, alkyl is linear or branched; and mixtures of said cations, or a composition comprising the compound of formula (1) and at least one further fluorescent whitening agent (FWA) selected from the compound of formula (4) and the compound of formula (9): ##STR00025## wherein n=0, 1, or 2, R.sub.x and R.sub.y independently of each other are H, C.sub.1-C.sub.4 alkyl, C.sub.2-C.sub.4 hydroxyalkyl, C.sub.1-C.sub.4 alkoxyalkyl, C.sub.2-C.sub.4 cyanoalkyl, wherein the alkyl residue is linear or branched, or (CH.sub.2).sub.iSO.sub.3.sup., (CH.sub.2).sub.i-phenyl, (CH.sub.2).sub.kCOOM.sub.1, (CH.sub.2).sub.kCOOR.sub.9, (CH.sub.2).sub.kCONH.sub.2, (CH.sub.2).sub.kOR.sub.9, wherein i is an integer from 1 to 3 and wherein k is an integer from 1 to 4, R.sub.9 is linear or branched C.sub.1-C.sub.3 alkyl, or R.sub.x and R.sub.y independently of each other together with the nitrogen atom form a morpholine, a piperidine or a pyrrolidine ring; and wherein M.sub.1 represents the corresponding cationic charge equivalent selected from the cations H.sup.+, alkali metal cation, Ca.sup.2+, ammonium, C.sub.1-C.sub.4 tetraalkyl ammonium, ammonium which is mono-, di-, tri- or tetra-substituted by C.sub.2-C.sub.3 hydroxyalkyl radicals, and NH(R.sub.10).sub.o(R.sub.11).sub.p.sup.+ with R.sub.10 being C.sub.1-C.sub.4 alkyl and R.sub.11 being C.sub.2-C.sub.3 hydroxyalkyl, wherein both o and p are an integer of 1 or 2 and op, and alkyl is linear or branched; and mixtures of said cations.

20. The size press or film press liquor of claim 19, wherein said composition comprises the compound of formula (1a): ##STR00026## wherein n is 0, 1, or 2; and M represents the corresponding cationic charge equivalent selected from the cations H.sup.+, alkali metal cation, Ca.sup.2+, Mg.sup.2+, ammonium, C.sub.1-C.sub.4 tetraalkyl ammonium, ammonium which is mono-, di-, tri- or tetra-substituted by C.sub.2-C.sub.3 hydroxyalkyl radicals, and NH(R.sub.10).sub.o(R.sub.11).sub.p.sup.+ with R.sub.10 being C.sub.1-C.sub.4 alkyl and R.sub.11 being C.sub.2-C.sub.3 hydroxyalkyl, wherein both o and p are an integer of 1 or 2, and op, alkyl is linear or branched; and mixtures of said cations, and wherein R.sub.x and R.sub.y independently of each other are H, linear or branched C.sub.1-C.sub.4 alkyl, linear or branched C.sub.2-C.sub.4 hydroxyalkyl, linear or branched C.sub.1-C.sub.4 alkoxyalkyl, linear or branched C.sub.2-C.sub.4 cyanoalkyl, or (CH.sub.2).sub.iSO.sub.3.sup.31 , (CH.sub.2).sub.i-phenyl, (CH.sub.2).sub.kCOOM, (CH.sub.2).sub.kCOOR.sub.9, (CH.sub.2).sub.kCONH.sub.2, (CH.sub.2).sub.kOR.sub.9, wherein i is an integer from 1 to 3 and wherein k is an integer from 1 to 4, R.sub.9 is linear or branched C.sub.1-C.sub.3 alkyl, or R.sub.x and R.sub.y independently of each other together with the nitrogen atom form a morpholine, a piperidine or a pyrrolidine ring.

21. A method for optically whitening cellulose-based materials comprising treating the cellulose-based material with at least one compound of formula (1): ##STR00027## wherein n is 0, 1, or 2; and wherein R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, R.sub.6, R.sub.7 and R.sub.8 independently of each other are H, linear or branched C.sub.1-C.sub.4 alkyl, linear or branched C.sub.2-C.sub.4 hydroxyalkyl, linear or branched C.sub.1-C.sub.4 alkoxyalkyl, linear or branched C.sub.2-C.sub.4 cyanoalkyl, phenyl substituted with SO.sub.3.sup., (CH.sub.2).sub.iSO.sub.3.sup., (CH.sub.2).sub.i-phenyl, (CH.sub.2).sub.kCOOM, (CH.sub.2).sub.kCOOR.sub.9, (CH.sub.2).sub.kCONH.sub.2, (CH.sub.2).sub.kOR.sub.9, wherein i is an integer from 1 to 3, k is an integer from 1 to 4, and R.sub.9 is linear or branched C.sub.1-C.sub.3 alkyl; or R.sub.1 and R.sub.2, or R.sub.3 and R.sub.4, or R.sub.5 and R.sub.6, or R.sub.7 and R.sub.8 independently of each other together with the nitrogen atom form a morpholine, a piperidine or a pyrrolidine ring; and wherein M represents the corresponding cationic charge equivalent selected from the cations H.sup.+, alkali metal cation, Ca.sup.2+, Mg.sup.2+, ammonium, C.sub.1-C.sub.4 tetraalkyl ammonium, ammonium which is mono-, di-, tri- or tetra-substituted by C.sub.2-C.sub.3 hydroxyalkyl radicals, and NH(R.sub.10).sub.o(R.sub.11).sub.p.sup.+ with R.sub.10 being C.sub.1-C.sub.4 alkyl and R.sub.11 being C.sub.2-C.sub.3 hydroxyalkyl, wherein both o and p are an integer of 1 or 2, and op, alkyl is linear or branched; and mixtures of said cations, or a composition comprising the compound of formula (1) and at least one further fluorescent whitening agent (FWA) selected from the compound of formula (4) and the compound of formula (9): ##STR00028## wherein n=0, 1, or 2, R.sub.x and R.sub.y independently of each other are H, C.sub.1-C.sub.4 alkyl, C.sub.2-C.sub.4 hydroxyalkyl, C.sub.1-C.sub.4 alkoxyalkyl, C.sub.2-C.sub.4 cyanoalkyl, wherein the alkyl residue is linear or branched, or (CH.sub.2).sub.iSO.sub.3.sup., (CH.sub.2).sub.i-phenyl, (CH.sub.2).sub.kCOOM.sub.1, (CH.sub.2).sub.kCOOR.sub.9, (CH.sub.2).sub.kCONH.sub.2, (CH.sub.2).sub.kOR.sub.9, wherein i is an integer from 1 to 3 and wherein k is an integer from 1 to 4, R.sub.9 is linear or branched C.sub.1-C.sub.3 alkyl, or R.sub.x and R.sub.y independently of each other together with the nitrogen atom form a morpholine, a piperidine or a pyrrolidine ring; and wherein M.sub.1 represents the corresponding cationic charge equivalent selected from the cations H.sup.+, alkali metal cation, Ca.sup.2+, ammonium, C.sub.1-C.sub.4 tetraalkyl ammonium, ammonium which is mono-, di-, tri- or tetra-substituted by C.sub.2-C.sub.3 hydroxyalkyl radicals, and NH(R.sub.10).sub.o(R.sub.11).sub.p.sup.+ with R.sub.10 being C.sub.1-C.sub.4 alkyl and R.sub.11 being C.sub.2-C.sub.3 hydroxyalkyl, wherein both o and p are an integer of 1 or 2 and op, and alkyl is linear or branched; and mixtures of said cations.

22. The method of claim 21, wherein said composition comprises the compound of formula (1a): ##STR00029## wherein n is 0, 1, or 2; and M represents the corresponding cationic charge equivalent selected from the cations H.sup.+, alkali metal cation, Ca.sup.2+, Mg.sup.2+, ammonium, C.sub.1-C.sub.4 tetraalkyl ammonium, ammonium which is mono-, di-, tri- or tetra-substituted by C.sub.2-C.sub.3 hydroxyalkyl radicals, and NH(R.sub.10).sub.o(R.sub.11).sub.p.sup.+ with R.sub.10 being C.sub.1-C.sub.4 alkyl and R.sub.11 being C.sub.2-C.sub.3 hydroxyalkyl, wherein both o and p are an integer of 1 or 2, and op, alkyl is linear or branched; and mixtures of said cations, and wherein R.sub.x and R.sub.y independently of each other are H, linear or branched C.sub.1-C.sub.4 alkyl, linear or branched C.sub.2-C.sub.4 hydroxyalkyl, linear or branched C.sub.1-C.sub.4 alkoxyalkyl, linear or branched C.sub.2-C.sub.4 cyanoalkyl, or (CH.sub.2).sub.iSO.sub.3.sup., (CH.sub.2).sub.i-phenyl, (CH.sub.2).sub.kCOOM, (CH.sub.2).sub.kCOOR.sub.9, (CH.sub.2).sub.kCONH.sub.2, (CH.sub.2).sub.kOR.sub.9, wherein i is an integer from 1 to 3 and wherein k is an integer from 1 to 4, R.sub.9 is linear or branched C.sub.1-C.sub.3 alkyl, or R.sub.x and R.sub.y independently of each other together with the nitrogen atom form a morpholine, a piperidine or a pyrrolidine ring.

23. A cellulose-based material comprising at least one compound of formula (1): ##STR00030## wherein n is 0, 1, or 2; and wherein R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, R.sub.6, R.sub.7 and R.sub.8 independently of each other are H, linear or branched C.sub.1-C.sub.4 alkyl, linear or branched C.sub.2-C.sub.4 hydroxyalkyl, linear or branched C.sub.1-C.sub.4 alkoxyalkyl, linear or branched C.sub.2-C.sub.4 cyanoalkyl, phenyl substituted with SO.sub.3.sup., (CH.sub.2).sub.iSO.sub.3.sup., (CH.sub.2).sub.i-phenyl, (CH.sub.2).sub.kCOOM, (CH.sub.2).sub.kCOOR.sub.9, (CH.sub.2).sub.kCONH.sub.2, (CH.sub.2).sub.kOR.sub.9, wherein i is an integer from 1 to 3, k is an integer from 1 to 4, and R.sub.9 is linear or branched C.sub.1-C.sub.3 alkyl; or R.sub.1 and R.sub.2, or R.sub.3 and R.sub.4, or R.sub.5 and R.sub.6, or R.sub.7 and R.sub.8 independently of each other together with the nitrogen atom form a morpholine, a piperidine or a pyrrolidine ring; and wherein M represents the corresponding cationic charge equivalent selected from the cations H.sup.+, alkali metal cation, Ca.sup.2+, Mg.sup.2+, ammonium, C.sub.1-C.sub.4 tetraalkyl ammonium, ammonium which is mono-, di-, tri- or tetra-substituted by C.sub.2-C.sub.3 hydroxyalkyl radicals, and NH(R.sub.10).sub.o(R.sub.11).sub.p.sup.+ with R.sub.10 being C.sub.1-C.sub.4 alkyl and R.sub.11 being C.sub.2-C.sub.3 hydroxyalkyl, wherein both o and p are an integer of 1 or 2, and op, alkyl is linear or branched; and mixtures of said cations, or a composition comprising the compound of formula (1) and at least one further fluorescent whitening agent (FWA) selected from the compound of formula (4) and the compound of formula (9): ##STR00031## wherein n=0, 1, or 2, R.sub.x and R.sub.y independently of each other are H, C.sub.1-C.sub.4 alkyl, C.sub.2-C.sub.4 hydroxyalkyl, C.sub.1-C.sub.4 alkoxyalkyl, C.sub.2-C.sub.4 cyanoalkyl, wherein the alkyl residue is linear or branched, or (CH.sub.2).sub.iSO.sub.3.sup., (CH.sub.2).sub.i-phenyl, (CH.sub.2).sub.kCOOM.sub.1, (CH.sub.2).sub.kCOOR.sub.9, (CH.sub.2).sub.kCONH.sub.2, (CH.sub.2).sub.kOR.sub.9, wherein i is an integer from 1 to 3 and wherein k is an integer from 1 to 4, R.sub.9 is linear or branched C.sub.1-C.sub.3 alkyl, or R.sub.x and R.sub.y independently of each other together with the nitrogen atom form a morpholine, a piperidine or a pyrrolidine ring: and wherein M.sub.1 represents the corresponding cationic charge equivalent selected from the cations H.sup.+, alkali metal cation, Ca.sup.2+, ammonium, C.sub.1-C.sub.4 tetraalkyl ammonium, ammonium which is mono-, di-, tri- or tetra-substituted by C.sub.2-C.sub.3 hydroxyalkyl radicals, and NH(R.sub.10).sub.o(R.sub.11).sub.p.sup.+ with R.sub.10 being C.sub.1-C.sub.4 alkyl and R.sub.11 being C.sub.2-C.sub.3 hydroxyalkyl, wherein both o and p are an integer of 1 or 2 and op, and alkyl is linear or branched; and mixtures of said cations.

24. The cellulose-based material of claim 23, wherein said composition comprises the compound of formula (1a): ##STR00032## wherein n is 0, 1, or 2; and M represents the corresponding cationic charge equivalent selected from the cations H.sup.+, alkali metal cation, Ca.sup.2+, Mg.sup.2+, ammonium, C.sub.1-C.sub.4 tetraalkyl ammonium, ammonium which is mono-, di-, tri- or tetra-substituted by C.sub.2-C.sub.3 hydroxyalkyl radicals, and NH(R.sub.10).sub.o(R.sub.11).sub.p.sup.+ with R.sub.10 being C.sub.1-C.sub.4 alkyl and R.sub.11 being C.sub.2-C.sub.3 hydroxyalkyl, wherein both o and p are an integer of 1 or 2, and op, alkyl is linear or branched; and mixtures of said cations, and wherein R.sub.x and R.sub.y independently of each other are H, linear or branched C.sub.1-C.sub.4 alkyl, linear or branched C.sub.2-C.sub.4 hydroxyalkyl, linear or branched C.sub.1-C.sub.4 alkoxyalkyl, linear or branched C.sub.2-C.sub.4 cyanoalkyl, or (CH.sub.2).sub.iSO.sub.3.sup., (CH.sub.2).sub.i-phenyl, (CH.sub.2).sub.kCOOM, (CH.sub.2).sub.kCOOR.sub.9, (CH.sub.2).sub.kCONH.sub.2, (CH.sub.2).sub.kOR.sub.9, wherein i is an integer from 1 to 3 and wherein k is an integer from 1 to 4, R.sub.9 is linear or branched C.sub.1-C.sub.3 alkyl, or R.sub.x and R.sub.y independently of each other together with the nitrogen atom form a morpholine, a piperidine or a pyrrolidine ring.

Description

EXAMPLES

(1) General Preparation Conditions

(2) A 4 l glass reactor equipped with a cooling and heating jacket connected to a thermostate, a propeller stirrer and a pH electrode was used for all preparation examples. Softened water was used for all preparation examples 1-4.

(3) 4-aminobenzenesulfonic acid (trivial name: sulfanilic acid) was first transferred into its sodium salt form by dissolving it in water at ambient temperature under stirring while adding 1 equivalent sodium hydroxide. A solution of sodium hydroxide with 10.4% strength was used for this purpose. Stirring was continued until a clear solution was obtained.

(4) The resulting solution of sodium sulfanilate had a content of 0.93 mol/kg.

(5) To 554.8 g of this solution, excess NaOH and water was added in the following amounts:

(6) 131.4 g of water and 204.8 g of a NaOH solution with 10.4% strength were added at ambient temperature under stirring. After the addition, stirring was continued for another 10 minutes. 891 g of a sodium sulfanilate solution with excess NaOH were obtained, containing 0.516 mol sodium sulfanilate and 0.532 mol NaOH (solution 1).

(7) 4,4-diamino-2,2-stilbenedisulfonic acid (trivial name: DAS) was first transferred into its sodium salt form by dissolving it in water at ambient temperature under stirring while adding 1 equivalent sodium hydroxide. A solution of sodium hydroxide with 10.4% strength was used for this purpose. Stirring was continued until a clear solution was obtained.

(8) The resulting solution of the DAS disodium salt had a content of 0.401 mol/kg (solution 2).

(9) General Analytical Conditions

(10) Extinction value: The obtained FWA solutions were characterized by measuring their extinction in a 1 cm cuvette at 350 nm, using an Uvikon XS spectrophotometer. Diluted samples containing 0.01 weight-% of the FWA solution were prepared prior to each measurement using demineralized water. The measured extinction value was then calculated back to a hypothetical aqueous solution containing 1.00 weight-% of the original FWA solution, the thus obtained value is called E.sub.1/1 value.

(11) HPLC: The obtained FWA solutions were analyzed with a HPLC device from Shimadzu, the peak detection took place at 350 nm. All detected peaks were summed up to 100 area-%.

(12) Preparation examples 1-3: the main component, representing the FWA molecule of formula (10) with n=1, R.sub.x and R.sub.y=CH.sub.2CH.sub.2OH and M=Na.sup.+, had a retention time of approx. 26 minutes. The FWA compound represented by formula (1) with n=1, R.sub.1 to R.sub.8=CH.sub.2CH.sub.2OH and M=Na.sup.+, had a retention time of approx. 45 minutes.

(13) Preparation example 4: the main component, representing the FWA molecule of formula (10) with n=1, R.sub.x and R.sub.y=[CH.sub.2CH(CH.sub.3)OH] and M=Na.sup.+, led to 3 HPLC peaks, as it is present in the form of different isomers. These 3 peaks had a retention time of 31-32 minutes. The FWA compound represented by formula (1) with n=1, R.sub.1 to R.sub.8=[CH.sub.2CH(CH.sub.3)OH] and M=Na.sup.+, had a retention time of approx. 49 minutes.

Preparation Example 1

(14) Reaction Step 1:

(15) 650 g of water were added to the reactor and the stirrer was started. Stirring was maintained through the course of the whole synthesis. 11.0 g of sodium chloride and 0.1 g of NaHCO.sub.3 were added and dissolved under stirring. The mixture was then cooled to 8 C. Then, 1.0 g of the dispersant DIADAVIN CA 40130 (from LEVACO Chemicals GmbH) were added and mixed in during 1 minute of continued stirring.

(16) 100.0 g of cyanuric chloride (0.542 mol) were then added to the reactor, followed by the addition of 100.0 g of water, which had a temperature of 8 C. Stirring was continued for 30 minutes to disperse the cyanuric chloride in water. The temperature was maintained at 8 C. and the pH remained in the range of 5.5 to 7.0.

(17) Then, 16.3 g of solution 2 (containing 0.0065 mol of DAS disodium salt) were added to the reactor with constant speed during 10 minutes. The pH in the reaction mixture was kept in the range of 3.8-4.5 by simultaneous addition of a NaOH solution with 10.4% strength. After completion of the addition of solution 2, the pH was adjusted to a value in the range of 4.3-4.7 with the NaOH solution. 5.1 g of the NaOH solution were added in total during and after addition of solution 2.

(18) Then, the addition of sodium sulfanilate solution containing excess NaOH (solution 1) was started. 891 g of solution 1 (containing 0.516 mol sodium sulfanilate) were added with constant speed over 2 hours and 30 minutes. The reaction temperature was allowed to raise to 16 C. during the first hour of addition, then the temperature was kept at 16 C. for the rest of the addition time. The pH in the reaction mixture maintained between 4.0 and 5.0 during the whole addition time.

(19) After completion of the addition, stirring was continued for another 20 minutes and then the temperature was raised to 20 C.

(20) Reaction Step 2:

(21) 654.7 g of solution 2 (containing 0.263 mol of DAS disodium salt) were added with constant speed over 30 minutes. During this addition of solution 2, the pH in the reaction mixture was raised to 6.5 and then kept at this value through addition of a NaOH solution with 10.4% strength. The temperature was maintained between 20-25 C. during the addition of solution 2. After completion of the addition, the temperature was raised to 65 C. during 1 hour and 15 minutes and then kept for another 1 hour and 20 minutes, while the pH was still maintained at 6.5 through addition of the NaOH solution. In total, 205.4 g of the NaOH solution with 10.4% strength were added during this reaction step.

(22) Reaction Step 3:

(23) 76.3 g of an aqueous solution of diethanolamine, having an active content of 89.6 weight-%, were added to the reaction mixture with constant speed during 9 minutes. The temperature was then raised to 100 C. during 45 minutes. The reaction started at approx. 75 C., this led to a drop of pH. When the pH value had reached 8.0, the addition of a NaOH solution with 10.4% strength was started and the pH was maintained at 8.0 through addition of this solution. After reaching 100 C., stirring was continued for further 3 hours while the pH was still maintained at 8.0. In total, 179.7 g NaOH solution were added during this step. The resulting FWA solution was then cooled to 55 C., filtered through a fluted paper filter, and allowed to cool furthermore down to 25 C.

(24) The resulting yellowish FWA solution had an E.sub.1/1 value of 57.

(25) HPLC analysis gave the following results: the main component according to the general formula (10) with n=1, R.sub.x and R.sub.y=CH.sub.2CH.sub.2OH and M=Na.sup.+ was detected with 91.1%. The FWA according to the general formula (1) with n=1, R.sub.1 to R.sub.8=CH.sub.2CH.sub.2OH and M=Na.sup.+ was detected with 4.3%.

Preparation Example 2

(26) The procedure as described in preparation example 1 was repeated with the following changes:

(27) Reaction Step 1:

(28) 65.2 g of solution 2 (containing 0.0261 mol of DAS disodium salt) and 845 g of solution 1 (containing 0.490 mol sodium sulfanilate) were used. 20.5 g of a NaOH solution with 10.4% strength were added during and directly after the addition of solution 2 to adjust the pH to 4.3-4.7.

(29) Reaction Step 2:

(30) 648.0 g of solution 2 (containing 0.260 mol of DAS disodium salt) were used. In total, 204.1 g of NaOH solution were added during this step.

(31) Reaction Step 3:

(32) In total, 169.3 g of NaOH solution were added during this step.

(33) The resulting yellowish FWA solution had an E.sub.1/1 value of 59.

(34) HPLC analysis gave the following results: the main component according to the general formula (10) with n=1, R.sub.x and R.sub.y=CH.sub.2CH.sub.2OH and M=Na.sup.+ was detected with 80.0%. The FWA according to the general formula (1) with n=1, R.sub.1 to R.sub.8=CH.sub.2CH.sub.2OH and M=Na.sup.+ was detected with 11.7%.

Preparation Example 3

(35) The procedure as described in preparation example 1 was repeated with the following changes:

(36) Reaction Step 1:

(37) 130.2 g of solution 2 (containing 0.0522 mol of DAS disodium salt) and 752.6 g of solution 1 (containing 0.436 mol sodium sulfanilate) were used. 40.9 g of a NaOH solution with 10.4% strength were added during and after the addition of solution 2 to adjust the pH to 4.3-4.7.

(38) Reaction Step 2:

(39) 631.1 g of solution 2 (containing 0.253 mol of DAS disodium salt) were used. In total, 199.8 g of NaOH solution were added during this step.

(40) Reaction Step 3:

(41) In total, 178.3 g of NaOH solution were added during this step.

(42) The resulting yellowish FWA solution had an E.sub.1/1 value of 57.

(43) HPLC analysis gave the following results: the main component according to the general formula (10) with n=1, R.sub.x and R.sub.y=CH.sub.2CH.sub.2OH and M=Na.sup.+ was detected with 66.6%. The FWA according to the general formula (1) with n=1, R.sub.1 to R.sub.8=CH.sub.2CH.sub.2OH and M=Na.sup.+ was detected with 20.1%.

Preparation Example 4:

(44) Reaction Steps 1 and 2 of the procedure as described in preparation example 1 were repeated. In reaction step 3, diisopropanolamine was used instead of diethanolamine.

(45) Reaction Step 3:

(46) 102.0 g of an aqueous solution of diisopropanolamine, having an active content of 84.9 weight-%, were added to the reaction mixture with constant speed during 12 minutes. The temperature was then raised to 100 C. during 45 minutes. The reaction started at approx. 75 C., this lead to a drop of pH. When the pH value had reached 8.0, the addition of a NaOH solution with 10.4% strength was started and the pH was maintained at 8.0 through addition of this solution. After reaching 100 C., stirring was continued for further 3 hours while the pH was still maintained at 8.0. In total, 176.3 g NaOH solution were added during this step. The resulting FWA solution was then cooled to .sub.55 C., filtered through a fluted paper filter, and allowed to cool furthermore down to 25 C.

(47) The resulting yellowish FWA solution had an E.sub.1/1 value of 53.

(48) HPLC analysis gave the following results: the main component appearing as 3 peaks (different isomers) according to the general formula (10) with n=1, R.sub.x and R.sub.y=[CH.sub.2CH(CH.sub.3)OH] and M=Na.sup.+ was detected with 90.2%. The FWA according to the general formula (1) with n=1, R.sub.1 to R.sub.8=[CH.sub.2CH(CH.sub.3)OH] and M=Na.sup.+ was detected with 3.6%.

Preparation Example 5

(49) 2875 g of an FWA solution obtained according to preparation example 2 were mixed at room temperature with 1711 g of demineralized water. The resulting solution was then concentrated and partially desalted in a membrane filtration process at 25 C. with a pressure of 40 bar. 1094 g of concentrated product having an E.sub.1/1 value of 140.1 were thus obtained.

(50) 100 g of this concentrated product were mixed for 15 minutes on as magnetic stirrer at ambient temperature with 15 g of softened water and 30 g of the polyvinyl alcohol solution Polyviol LL 2850 (from Wacker), having a strength of 25 weight-%. A formulation with an E.sub.1/1 value of 97 and a polyvinyl alcohol content of 5.2 weight-% was obtained.

Preparation Example 6

(51) 100 g of the concentrated product as described in preparation example 5 above were first mixed for 5 minutes on as magnetic stirrer at ambient temperature with 30 g of softened water, then 15 g of melted polyethylene glycol 1550 in liquid form, having a temperature of 60 C., were added. Mixing was continued for another 15 minutes. A formulation with an E.sub.1/1 value of 97 and a polyethylene glycol content of 10.3 weight-% was obtained.

Application Examples

(52) Coating Application:

(53) A paper coating color was prepared from the following raw materials: 945 g of the GCC powder Hydrocarb 90 (from Omya) 405 g of the kaolin Kaolin KN 83 Granulat (kaolin content 99%, from Amberger Kaolinwerke) 8.5 g of the dispersant Polysalz S (approx. 40% solids, from BASF) 270 g of the binder Litex P 7110 (styrene-butadiene latex with approx. 50% solids, from Synthomer) 40 g of the polyvinyl alcohol solution Polyviol LL 2850 having 25% solids (from Wacker) 100 g of an aqueous solution of the carboxymethyl cellulose Walocel CRT 10 G (from Dow Wolff Cellulosics) having 10% solids 640.2 g of demineralized water 6.5 g of aqueous sodium hydroxide solution with a strength of 5%
For preparing the coating color, the above mentioned materials were mixed in the following manner using the given amounts: Polysalz S was first stirred into demineralized water at ambient temperature. To this mixture, GCC and kaolin were added and mixed in with a dissolver plate at 500 rpm for 5 minutes. Then the mixture was dispersed with an Ultra-Turrax device at 7000 rpm for 2 minutes. After this, the binder, the polyvinyl alcohol solution and the carboxymethyl cellulose solution were added subsequently under stirring. The pH of the coating color was adjusted to the range 8.4-8.6 by adding the aqueous sodium hydroxide solution.

(54) Stirring was continued for another 5 minutes. A paper coating color with a solids content of 62.2% and a pigment content of 55.7% was obtained.

(55) The coating color was separated into 19 portions of 100 g. The liquid FWA's according to the preparation examples 1-6 were diluted prior to the addition to an E.sub.1/1 value of 50 by adding demineralized water. The FWA preparations were then added to the coating color samples in amounts of 0.37 g/0.75 g/1.12 g and stirred in for 5 minutes. For comparison purposes, the coating color without addition of FWA was applied in the same manner as described below: The coating color samples were each applied to wood-free base paper sheets having a basis weight of approx. 83 g/m.sup.2. For this purpose, the laboratory coater Erichsen K-Control-Coater, model K 202, was used. The coated papers were then dried on a drum dryer at 95 C. for 1 minute and afterwards stored for 4 hours at 23 C. and a relative humidity of 50%. The applied coat weight was in the range of 14-16 g/m.sup.2. Then, CIE whiteness and ISO brightness values were determined by using a Datacolor ELREPHO SF 450 device.

(56) The obtained results are shown in Table 1 below.

(57) TABLE-US-00001 TABLE 1 FWA amount (% related to FWA from dry matter in the coating preparation ISO brightness CIE colour) example No. (%) whiteness no FWA used no FWA used 81.0 66.9 0.59 1 86.9 87.3 1.21 1 89.7 95.9 1.80 1 91.3 100.6 0.59 2 87.1 88.3 1.21 2 89.9 97.0 1.80 2 91.6 101.6 0.59 3 87.3 88.4 1.21 3 90.1 97.4 1.80 3 91.9 102.2 0.59 4 86.8 87.1 1.21 4 89.8 96.5 1.80 4 91.3 100.9 0.59 5 87.1 88.4 1.21 5 90.3 98.0 1.80 5 91.9 102.3 0.59 6 87.2 88.3 1.21 6 90.2 97.6 1.80 6 91.9 102.4

(58) It can be clearly seen that all tested FWA's lead to a significant increase of whiteness and brightness, when applied in a paper coating color.

(59) Size Press Application:

(60) The liquid FWA's according to the preparation examples 1 and 2 were first diluted to an E.sub.1/1 value of 50 by adding demineralized water. Size press liquors with these FWA solutions were then prepared as follows: 1.67 g/3.33 g/5.00 g, respectively, of each FWA solution were blended at room temperature with 192.3 g of an aqueous solution of the starch Perfectamyl A 4692 (from AVEBE) having a strength of 6.5 weight-%, then filled up to 250.0 g with demineralized water, and finally stirred for 5 minutes on a magnetic stirrer.

(61) An unsized, woodfree paper with a basis weight of 107 g/m.sup.2 was used for the surface sizing trials. The size press liquors were applied with a laboratory size press (from the company Mathis, type HF) using a speed of 2.5 m/min and a pressure of 2.5 bar.

(62) Weighing the paper directly before and after the size press treatment yielded a wet pickup of the paper of approx. 90% for all treatment liquors.

(63) For comparison purposes, the base paper was treated in an analogous manner without addition of an FWA to the size press liquor.

(64) The treated papers were dried in each case on a drying cylinder for 2 minutes at 105 C., and afterwards stored in norm climate (23 C., 50 relative humidity) for 24 hours. Then, the ISO brightness and CIE whiteness values were determined using a Datacolor Elrepho SF 450 device.

(65) The obtained results are summarized in the following Table 2.

(66) TABLE-US-00002 TABLE 2 FWA amount FWA (% related to from preparation ISO brightness size press liquor) example No. (%) CIE whiteness no FWA used no FWA used 85.1 80.4 0.67 1 103.9 136.7 1.33 1 107.2 144.9 2.0 1 109.2 148.8 0.67 2 105.0 138.9 1.33 2 108.2 145.7 2.0 2 109.6 148.1

(67) It can be seen from the obtained results that the tested FWAs lead to a significant increase of whiteness and brightness, when applied to the paper surface in a size press application.

(68) Wet End Application

(69) Handsheets containing the FWA's from preparation example 1 and 2 were prepared as follows: an aqueous pulp suspension, containing 70 parts by weight of short-fiber chemical pulp and 30 parts by weight of long-fiber chemical pulp and having a freeness of 35 SR and a consistency of 0.625 weight-% was used to prepare the handsheets. The liquid FWAs from example 1 and 2 were diluted prior to the handsheet preparation to an E.sub.1/1 value of 0.50 by adding demineralized water.

(70) For each handsheet, 800 ml of the pulp suspension were placed in a beaker and stirred by means of a magnetic stirrer. From each diluted FWA solution, 3.0 g/6.0 g/9.0 g, respectively, were added. The pulp suspension was then allowed to stir for 10 minutes.

(71) A handsheet former was then used to prepare handsheets of approx. 5 g dry weight and a basis weight of approx. 120 g/m.sup.2. In each case, a wet filter paper was placed on the wire of the sheet former, then the pulp suspension was poured onto the wire and the water was removed by a suction pump. A second filter paper was used to cover the wet handsheet. Then the handsheet was pressed and finally dried on a drying cylinder for 2 minutes at 105 C. The handsheets were afterwards stored in norm climate (23 C., 50 relative humidity) for 24 hours. Then, the ISO brightness and CIE whiteness values were determined using a Datacolor Elrepho SF 450 device.

(72) For comparison purposes, a handsheet without addition of FWA was prepared and evaluated in an analogous manner.

(73) The obtained results are summarized in the following Table 3.

(74) TABLE-US-00003 TABLE 3 FWA from ISO Amount of diluted FWA preparation brightness CIE solution; E1/1 value 0.50 (g) example No. (%) whiteness no FWA used no FWA used 81.6 65.4 3.0 1 97.7 116.8 6.0 1 101.6 127.3 9.0 1 103.7 132.1 3.0 2 99.3 120.5 6.0 2 102.4 128.0 9.0 2 103.3 130.1

(75) It can be seen from the obtained results that the tested FWA's lead to a significant increase of whiteness and brightness, when applied to papermaking pulp prior to sheet formation (wet end application).