DE1207331B - Optical brighteners for textiles - Google Patents

Description

Optical brighteners for textiles Optical brighteners have been around for some Years for the treatment of textiles, especially for washing, widespread use found and are said to be of yellow or a color deviating from white, the white textiles can counteract this, especially after repeated washing. Such optical Lighteners can also improve dyed textiles by making their color brighter do. They are also widely used to make other cellulosic materials, especially paper to make whiter.

Of the compounds known as optical brighteners, those of German Auslegeschrift 1 020 026 are most similar to those that can be used according to the invention. That of the compounds of this German patent application 1 020 026 which comes closest to the compounds according to the invention contains the group S02CHa on the stilbene ring. In the compounds which can be used according to the invention, the sulfur-containing group has the general formula SO2R, where R is an alkylene chain with a hydrophilic substituent such as a hydroxyl, alkoxy, cyano, carboxy, carbalkoxy and polyoxyalkyl group. The hydrophilic substituent gives the compounds very good substantivity towards various textile fibers, in particular polyamide fibers.

Fabric swatches contained in the compound according to the invention Lye washed were. noticeably brighter and whiter than those in that known compound containing alkalis were washed.

The new compounds of the invention to be used according to the invention as optical brighteners have the general formula wherein each of the groups Y, which can be identical or different, is a hydrogen atom or a non-chromophoric or non-auxochromic group and R is an alkylene group with a straight or branched chain with preferably at least 2 carbon atoms which carries at least one hydrophilic substituent, A is a - Or polynuclear aromatic or heterocyclic radical of which two adjacent carbon atoms belong to the triazole ring and which is derived, for example, from benzene, naphthalene, acenaphthene, indazole (5- or 6-) or pyrazole, Z is a hydrophilic group and m is an integer of 1 to 3 is.

The hydrophilic group on A can, for example, be a —SO3H or —COOH group if desired in the form of a salt, for example an alkali salt may exist.

The compounds of the invention are generally good in water or Wetting agent solutions are dispersible and have a well-balanced substantivity for different textile fibers. Those compounds that do not have a hydrophilic group, such as a —COOH or —SO3H group on the substituent A are in particular for the treatment of hydrophobic synthetic or semi-synthetic fibers, such as polyamide and cellulose triacetate fibers and especially polyester fibers. Polyester fibers are becoming increasingly important, but up until now it has been difficult to to make optical brighteners with good substantivity for them. The presence a hydrophilic group in residue A reduces the substantivity of the compound towards polyester fibers, but increases the substantivity towards cellulose fibers, while the substantivity to fibers from polyamides and wool is essentially unaffected remain. The compounds of the invention thus represent represent a group of optical brighteners with particularly adaptable usability.

Of the compounds of the above formula, those are preferred in which R is an oxy, alkoxy, cyano, carboxy, carbalkoxy, polyoxyalkyl or contains oxy group partially esterified with a polycarboxylic acid. examples for such groups are: - CH2CH2COOR2 - CH2CH2CN - CH2COOR2 - CH2CH20 - CO - CH = CH - COOR2 - CH2CH2CH2COOR2 - CH2CH20 - CO - CH2CH2 - COOR2 - (CH2CH20), R2 - (C3Hs0) "R2 - CH2CH (OR2) CH20R.2 - CH2CH (OH) CH20CH2CH20CHs where R_ is hydrogen or an alkyl group, for example a methyl, ethyl, propyl, isopropyl, butyl group etc .. and n is an integer from 1 to 10. The optical brighteners of the invention include also the sulfuric acid and phosphoric acid esters of those compounds that have a Hydroxyl group contained in the R group.

If the groups Y are not hydrogen, they can, for example low molecular weight alkoxy groups, such as methoxy or ethoxy groups, or halogen atoms, such as chlorine, bromine or iodine atoms. Preferred are those compounds in where such substituents in the o- or p-position are side chains.

The compounds can be used in soaps, wetting and cleaning agents, detergents and other textile treatment agents.

The compounds according to the invention can be according to any convenient Method. In general, a sulfinic acid group (-SO2H) in a group -S02R, in which R has the meaning given above, converted. Therefor are generally compounds that have an epoxy group or a double bond contain or compounds which, under suitable conditions, with the sulfinic acid residue react to form acid, for example aliphatic halohydrins.

The preparation of the sulfinic acid used as the starting material can be carried out by any method that is customary per se. There is a suitable method for example, that you have the underlying sulfonic acid, for example by treating with thionyl chloride or phosphorus tri- or pentachloride, in one Acid chloride transferred, which can then be reduced to the corresponding suffic acid can.

The preparation of the invention as optical brightening agents However, compounds to be used are not the subject of the invention here. this also applies to the manufacturing processes explained in the examples.

The parts mentioned in the examples are based on weight. was prepared as follows: A solution of 31.1 parts of 4-amino (2-carboxyethyl) sulfonyl stilbene. 4.1 parts of sodium hydroxide and 6.9 parts of sodium nitrite in 500 parts of water are indirectly diazotized at 8 to 10 ° C. with 25 parts of concentrated hydrochloric acid. The suspension of the diazo compound is coupled with a solution of 23.0 parts of sodium naphthionate in 200 parts of water. A solution of 200 parts of sodium acetate is added. to control the pH during coupling.

After coupling is complete, the dye is filtered off, in 500 Parts of pyridine dissolved and 60 parts of copper sulfate and 75 parts of ammonia in 100 Share refluxed water until the red color has completely disappeared.

When the oxidation is complete, the triazole is precipitated by acidification, converted into the disodium salt and recrystallized from aqueous alcohol. The 4-amino- (2-carboxyethyl) -sulfonylstilbene used as starting material for this example can be obtained by reducing a compound of the formula 4-Nitrostilbene-2-sulfonic acid (29 g) was dissolved in 1.6 liters of 50 ° aqueous ethanol. The solution was refluxed with 10.8 g of acrylic acid for 7 hours. On cooling the solution crystallized the product was filtered off, washed and recrystallized from alcohol, mp 238 ° C.

Undyed textiles made from synthetic polyamide fibers are treated in a bath at a ratio of 1: 40 for 1 hour at 85 ° C. which contains 0.4 g of formic acid and 0.15 g of the triazole compound of this example per liter. After rinsing and drying, the treated material has a considerably whiter appearance than before treatment. was prepared as follows: A solution of 33.1 parts of 4-amino (2-carboxyethyl) sulfonyistilbene, 4.1 parts of sodium hydroxide and 6.9 parts of sodium nitrite in 500 parts of water is added at 8 to 25 parts of concentrated hydrochloric acid Indirectly diazotized at 10 ° C. The suspension of the diazo compound is coupled with a solution of 21.3 parts of 6-aminoindazole-4-sulfonic acid in 300 parts of water. A solution of 200 parts of sodium acetate is added to control the pH of the reaction mixture.

After the coupling is complete, the dye is filtered off, washed, dissolved in 500 parts of pyridine and with 60 parts of copper sulfate and 75 parts of ammonia heated to reflux in 100 parts of water. until the color is gone.

After the oxidation, the triazole is precipitated by acidification, in transferred the disodium salt and recrystallized from aqueous alcohol.

1 part of white linen made from pillow cases and sheets is washed in the usual way at 90 to 100 ° C. in 10 parts of washing liquid. which contains 3 g curd soap, 2 g sodium carbonate and 0.003 g of the triazole compound of this example per liter. A brilliant white was achieved. was prepared as follows: A solution of 15.15 parts of 4-amino-2- (ß-oxyethylsulfonyl) stilbene in 150 parts of acetone is acidified by adding 12.5 parts of hydrochloric acid and directly with an aqueous solution of 3.45 parts Sodium nitrite diazotized at 8 to 10 ° C.

The diazonium compound is with a solution of 7.15 parts of ß-naphthylamine and 5 parts of hydrochloric acid in 100 parts of water. and a solution of 50 parts Sodium acetate in 100 parts of water is added.

After the coupling is complete, the dye is salted out and filtered off and washed with dilute hydrochloric acid.

The wet dye is dissolved in 200 parts of pyridine and mixed with 30 parts Copper sulfate in 50 parts of water and ammonia in excess heated to reflux, until the color has completely disappeared. The crude triazole of those given above Formula is precipitated by diluting the reaction mixture, filtered off, with Washed water and recrystallized from acetic acid.

30 parts of the triazole compound described in this example are ground with 60 parts of sodium bisulfate and 910 parts of a condensation product of naphthalenesulfonic acid and formaldehyde to give a fine, homogeneous powder.

Polyethylene terephthalate threads treated with a bath at a ratio of 1:30 for 30 minutes at 80 to 100 ° C. the bath containing 2% of the above powder and 1 to 2 cc ammonia per liter, have a lighter appearance after rinsing and drying than the untreated material. Further compounds which can be used as optical brighteners according to the invention are those of the following formulas

Claims (1)

Claim: Use of compounds of the general formula YY IN\ Y CH = CH > N \ j - (Z) m-1 N YY SO2R wherein each of the groups Y, which can be identical or different, is a hydrogen atom or a non-chromophoric or non-auxochromic group, such as a low-molecular alkoxy group or a halogen atom, which are preferably in the o- and / or p-position to the side chain, and R an alkylene group with straight or branched chain with preferably at least 2 carbon atoms, which has at least one hydrophilic substituent, such as a hydroxyl group, an alkoxy, cyano, carboxy, carbalkoxy, polyoxyalkyl group or a partially esterified with a polycarboxylic acid or a hydroxyl group with sulfuric acid or Phosphoric acid esterified hydroxyl group, A is a mononuclear or polynuclear aromatic or heterocyclic radical of which two adjacent carbon atoms belong to the triazole ring and which is derived from benzene, naphthalene, indazole (5- or 6-) or pyrazole, Z is a hydrophilic group such as -SO3H or -COOH group, if desired in the form of a Salt, and m is an integer from 1 to 3, as optical brighteners for textiles. Considered publications: German Auslegeschrift No. 1020 026. When the application was announced, two staining tables with test reports were laid out.