Optical brighteners

1. A compound of formula (1), (2) or (3)

wherein

M is hydrogen, an alkali metal ion or an ammonium ion,

A 1 is —OR 1 , —NHR 1 , N-morpholinyl or 1-piperidyl,

A 2 is —OR 2 , —NHR 2 , N-morpholinyl or 1-piperidyl,

E 1 , E 2 , E 3 and E 4 are each independently of the others —O—, —NH— or —NR 9 —, wherein R 9 together with R 4 , R 6 , R 2 or R 12 forms an ethylene radical,

R 1 to R 6 , R 11 and R 12 are each independently of the others hydrogen, alkyl, alkoxy, aryl, aralkyl, alkoxyalkyl, hydroxyalkyl, aminoalkyl or a group of the formula —(C n H 2n Y) m —R 7 , wherein Y is —O—, —NH—, —NR 8 —, —CONH— or —CONR 8 —, R 7 is hydrogen, alkyl or aryl and R 8 is alkyl or aryl, n is a number from 2 to 6 and m is a number from 1 to 10, or pairs of two radicals R 1 and R 2 , R 3 and R 4 , R 5 and R 6 or R 11 and R 12 together form a bivalent radical of the formula —CH 2 CH 2 OCH 2 CH 2 — or, when E 1 , E 2 , E 3 or E 4 is —NR 9 —,

R 4 , R 6 , R 2 or R 12 together with R 9 forms an ethylene radical,

R 10 , R 13 , R 14 and R 15 are each independently of the others alkyl, alkenyl, aryl or aralkyl,

X 1 and X 2 are each independently of the other 1,2-cyclohexanediyl, a group of the formula —(C n H 2n ) m — or a group of the formula —(C n H 2n Y) m —, wherein Y is —O—, —NH—, —NR 8 —, —CONH— or —CONR 8 — and R 8 is alkyl or aryl, n is a number from 2 to 6 and m is a number from 1 to 10,

Y 1 and Y 2 are each independently of the other 1,2-cyclohexanediyl, a group of the formula —(C n H 2n ) m — or a group of the formula —(C n H 2n Y) m —, wherein Y is —O—, —NH—, —NR 8 —, —CONH— or —CONR 8 — and R 8 is alkyl or aryl, n is a number from 2 to 6 and m is a number from 1 to 10 and A − is a singly charged anion or the two A − form a doubly charged anion,

R 16 , R 17 , R 18 and R 19 are each independently of the others hydrogen, 2-hydroxyethyl, 2-aminoethyl or 3-aminopropyl,

R 20 , R 21 , R 22 and R 23 are each independently of the others alkyl, and

A 3 and A 4 are 2-hydroxyethylamino, 3-dimethylaminopropylamino or 3-diethylaminopropylamino.

2. A compound of formula (2) or (3) according to claim 1 , wherein the substituents A 1 and A 2 , A 3 and A 4 , E 1 and E 2 , X 1 and X 2 , R 16 and R 18 , R 17 and R 19 , R 20 and R 22 and also R 21 and R 23 are in each case identical.

3. A compound of formula (1) according to claim 1 , wherein the substituents E 1 and E 2 , E 3 and E 4 , X 1 and X 2 , Y 1 and Y 2 , R 3 and R 5 , R 4 and R 6 , R 14 and R 15 , R 1 and R 11 , R 2 and R 12 and also R 10 and R 13 are in each case identical.

4. A compound of formula (1) or (2) according to claim 1 , wherein X 1 and X 2 are ethylene or trimethylene.

5. A compound of formula (3) according to claim 1 , wherein R 20 , R 21 , R 22 and R 23 are methyl or ethyl.

6. A compound of formula (2) or (3) according to claim 1 , wherein A 1 , A 2 , A 3 and A 4 are amino, methylamino, 2-hydroxyethylamino, 3-dimethylaminopropylamino or ethoxy.

7. A compound of formula (1) according to claim 1 , wherein R 1 to R 6 and R 10 to R 15 are methyl.

8. A process for the preparation of a compound of formula (2) according to claim 1 wherein the substituents A 1 and A 2 , A 3 and A 4 , E 1 and E 2 , X 1 and X 2 , R 16 and R 18 , R 17 and R 19 , R 20 and R 22 and also R 21 and R 23 are in each case identical, which process comprises reacting cyanuric chloride by known methods with, in succession in any order, a compound of formula (4)

a compound of formula (5)

and a compound of formula (6)

wherein M, A 1 , E 1 , X 1 , R 3 and R 4 are as defined in claim 1 .

9. A process for the preparation of a compound of formula (3) according to claim 1 wherein the substituents A 1 and A 2 , A 3 and A 4 , E 1 and E 2 , X 1 and X 2 , R 16 and R 18 , R 17 and R 19 , R 20 and R 22 and also R 21 and R 23 are in each case identical, which process comprises reacting cyanuric chloride by known methods with, in succession in any order, a compound of formula (4)

a compound of formula (7)

and a compound of formula (8)

wherein M, A 3 , E 1 , R 20 and R 21 are as defined in claim 1 .

10. A method for the optical brightening of natural, semi-synthetic or synthetic textile fibres, which comprises treating said fibres in an aqueous medium with an effective amount of a compound of formula (1), (2) or (3) according to claim 1 .

11. A method for the optical brightening of paper, which comprises treating said paper fibres in an aqueous medium with an effective amount of a compound of formula (1), (2) or (3) according to claim 1 .

12. A method of increasing the SPF of a textile fibre material, comprising the treatment of the textile fibre material with 0.05–3.0% by weight, based on the weight of the textile fibre material, of one or more compounds of formula (1), (2) or (3) according to claim 1 .

13. A composition for brightening synthetic or natural organic materials, comprising water, a compound of formula (1), (2) or (3) according to claim 1 and optionally further adjuvants.