DD154778A3 - METHOD FOR PRODUCING AN OPTICAL LIGHTING AGENT OF THE BISTRIAZINYLAMINOSTILS SERIES - Google Patents

Abstract

The invention relates to the preparation of the optical brightener of the formula given in a particularly pure and readily filterable crystal form. It is obtained by stepwise condensation in aqueous medium of cyanuric chloride with 3-aminobenzenesulfonic acid, 4,4'-diaminostilbene-2,2'-disulfonic acid and monoethanolamine, followed by adjustment of the solution of the condensation product obtained to a density of 1.145 to 1.155 by addition of sodium chloride at temperatures between 90 and 100 degrees C slow cooling to z. Start of nucleation and complete crystallization at the nucleation temperature or a temperature below 5 ° C below.

Description

VEB CHEMIEKOMBIMT BMSRPELD

Bitterfeldj 12, July 1979 1969

Process for the preparation of an optical suspension of the Bistriazinylainino ™ stilbene series

Field of application of the invention

The invention "relates to the preparation of the optical Aufhe resolution sinit te Is the Pormel

f \

-MH-C

CH =

HNCH ₂ CH ₂ OH

kte r istji ic .. ^ d G_r_be_kannt e n_jfe ^ S illi isfillSIl- SI & §

Derivatives of 4 j 4 '-bistriazinylamino stilbene-2 _s 2 ^! ~ disulfo.ncäure are known as optical brightening agents "The brightener of the formula given is the first time in the 'SE-PS

ι ο, J υ ι .. \ r> /; j - · ο u li χ .ou

- 2. »2 1 4 3 3 31969

He mentioned 814,903 obtained by 2 moles of cyanuric chloride in any order gradually with 1 mole of 4 * 4'-diaminostilbene-2,2'-disulfonic acid, 2 moles of 3-aminobenzenesulfonic acid and 2 moles of monoethanolamine are condensed. Technically-economically advantageous to carry out the condensation of cyanuric chloride with the aromatic aminosulfonic acid in the first stage in an organic solvent-free aqueous medium (DE-AS 1,250,883-O) ₉ However, a disadvantage is the non-quantitative reaction of cyanuric chloride with a Coarse-grain fraction> 160 Me By separating the unreacted cyanuric chloride after 1 _e condensation stage prevents cyanuric chloride in the other stages of preparation with other substances to undesirable by-products (DD-PS 55 668) e The separation of the water-soluble brightener of the above The formula is carried out by salting out or acidification. According to DE-AS 1 090 168, the reaction mixture is allowed to flow into a salt solution, whereby the brightener immediately precipitates in finely crystalline form, which entrains many impurities and can not be readily filtered. "Acidification according to DE-OS 1 811 715 is first the acid form, the very s is filterable, separated. After separation, it must be dispersed in water and adjusted to pH 7 with sodium hydroxide solution in order to obtain the desired tetrasodium salt from the resulting solution by evaporation. "Also under the salting out conditions of DD-PS 55 668 (addition of a maximum of 10% by mass NaCl to the hot reaction solution and cooling it to room temperature), a brightener which is only moderately filterable is obtained.

Zie_! _ri .der. invention

The aim of the invention is the preparation of the optical brightening agent of the formula given above in very high purity and with improved filterability _e

- 3 · - .21 4 3 3 3 1969

.Darlegation, "de.s, We s ns, the _ι Br f indung

It has been found that the stated object is achieved in full, when cyanuric chloride in an aqueous medium, first with a water-soluble salt of 3-aminobenzenesulfonic acid in a molar ratio of 1; 1, then the formed connection with 4 _? 4 ^f ~ 2) iaminostilbene-2j2'-disulphonic acid or its salts in a molar ratio of about 2; 1, the now resulting secondary condensation product with monoethanolamine in a molar ratio of about 1: 2 condenses on known VJeise, the solution of the tertiary condensation product at temperatures between 90 and 100 C by addition of sodium chloride to a density of 1.145 · adjusted to 1.1550 and below Stir slowly, cool to a temperature between 70 and 90 ^° C. until nucleation occurs, then keep at the nucleation temperature up to a maximum of 5 ^° C. until complete crystallization of the optical brightener of the formula given above and finally separate from the mother liquor in the same temperature range.

The brightener obtained in this way is free from the impurities usually produced by the reaction of the flask, such as poly-4-y 4'-diamino-styrene-2, 2'-di-sulfonic acid, hydroxy- and tetra-alkanoic amino compounds.

Execution As 1

In a mixture of 320 Vo - ropes of water, 100 parts by Ma ₀ ice and 1.8 by volume, parts by a $ 10 ligninsulfonsäurelösung weight are entered ₀ parts by cyanuric chloride with stirring for 24 ₅ 7 Ma and stirring a short time "The suspension is then stirred. Stir with a solution of 23? 1 part by weight of 3-aminobenzene · sulfenic acid and 7 _; 1 ₀ parts by Ma Fatriiuncarbonat in 120 vol «~ parts of water are added. It is stirred at temperatures of 10 to 15 C until the 3-Aminobenzolsulionsäure is consumed "Ifunrcehr wird..reaction mixture with a solution of 23 5 5 Ma ₀ -TeiIeη 4.4 ^? Diamino sti Lben-2 _s 2 ^f -rdisulf oic acid and

-4- 214333 1969

7 Ma _c ~ parts of sodium carbonate in 250 parts by volume of water added »The resulting mineral acid is blunted with sodium carbonate and stirred at pH 7 and temperatures of 35 to 40 ⁰ C for one hour _e Then 9 ₅ 9 parts by weight monoethanolamine "laughing two hours of stirring at 90 to 95 C, the solution with sodium chloride at a density of 1,145 adjusted to 1,150 sub Kühren is allowed to now cool off until the start of Eeimbildung" in the 'nucleation temperature to a maximum of 5 ⁰ C below is now held for several hours is, until complete crystallization achieved "and aspirated at the same temperature and dried in the usual manner" is obtained 70.5 parts by _e Ma of the brightener of the above formula in excellent quality "

Claims (1)

-5-2 14333-, 969 Process for the preparation of the optical brightener of the formula 1 in .in a particularly pure and readily filterable crystal form by condensation in an aqueous medium of Cj ^ anurchlorid with a water-soluble salt of 3-aminobenzenesulfonic acid in a molar ratio of 1 % 1 _S subsequent reaction of the resulting compound with 4> 4 ^c -l ' ^| i3-minostilbene ~ 2 _? 2'-disulfonic acid or its salts in a molar ratio of about 2: 1, further reaction of the secondary condensation product now obtained with monoethanolamine in an egg ~ ratio of about 1: 2, subsequent crystallization and isolation, characterized in that the solution of tertiary condensation product at temperatures between 90 and 100 C by addition of sodium chloride to a density of 1.145 to 1.125 is set, with stirring until the beginning of Keira formation at temperatures - 6 - 2 14 3 3 3 1969 is dungßteraperatur up to 5 ⁰ G including up to complete crystallization held 'and then sucked the same temperature range "- cooled balmy 90 ⁰ C slowly between 70 and · at DER Keimbil