DE1262206B - Optical brighteners - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. Cl .:

Number:
File number:
Registration date:
Display day:

D061

German class: 8i-l

1262206
F34734IVc / 8i
August 19, 1961
March 7, 1968

The invention relates to the use of fluorescent, practically colorless coumarin compounds the general formula

(R ₂ ) "

Optical brightening agents

Applicant:

Paint factories Bayer Aktiengesellschaft,

5090 Leverkusen

Named as inventor:

Dr. Roderich Raue,

Dr. Alfred Brack, 5090 Leverkusen

as an optical brightening agent.

In this general formula, R denotes hydrogen or a lower alkyl radical, while Ri and R2 denote hydrogen or non-coloring substituents, where two adjacent substituents can form a fused ring, and in which m is a number from 1 to 4 and η is a number of 1 to 3 is.

Examples of non-coloring substituents are alkyl, alkenyl, aralkyl or aryl radicals called, which can also be substituted, e.g. B. by oxy, alkoxy, amino or ammonium groups, by halogen and cyano or by carboxylic acid and sulfonic acid groups; no more Coloring substituents are halogen atoms and the nitrile group, as well as the sulfonic acid group and the sulfonamide group, which can also be substituted; the carboxylic acid group can also be used as well as carboxylic acid ester and carbonamide groups, which can likewise be substituted; Acyloxy and carbamyloxy groups may also be mentioned.

Particularly suitable lightening agents are the coumarin compounds of the formula given when R is hydrogen. Coumarin compounds which have an acidic group, in particular contain the sulfonic acid group, can be used primarily for lightening natural fiber materials, z. B. of wool, while coumarin compounds, which basic groups, z. B. tertiary amino groups or quaternary ammonium groups, contain themselves to lighten Materials made of polyacrylonitrile or cellulose esters are suitable. Coumarin compounds that are neither acidic still contain basic groups and are therefore sparingly soluble in water, are suitable for Lightening of materials made of synthetic polycondensates such as polyesters, polyamides and polyurethanes, as well as for lightening materials made of polyacrylonitrile, polystyrene or cellulose esters.

The optical brightening agents to be used in the present invention are according to various methods obtainable, for example by reacting 2-oxybenzaldehyde or its substitution products with thienylacetic acid or its substitution products and functional derivatives.

As suitable substitution products of 2-oxybenzaldehyde Examples include: 5-chloro-2 - oxybenzaldehyde, 5 - bromine - 2 - oxybenzaldehyde, 3,5 - dichloro - 2 - oxybenzaldehyde, 5 - methyl - 2 - oxy-

benzaldehyde, 3,5-dimethyl-2-oxybenzaldehyde and 5-tert-butyl-2-oxybenzaldehyde.

Suitable substitution products and functional derivatives of thienylacetic acid include 5-chlorothienyl-2-acetic acid, 5-bromothienyl-2-acetic acid, 5-methylthienyl-2-acetic acid, benzthiophene-3-acetic acid, the methyl, ethyl, propyl or butyl esters of these acids or of thienyl-2-acetic acid; also thienyl-2-acetonitrile, 5-chlorothienyl-2-acetonitrile and 5-bromothienyl-2-acetonitrile.

Coumarin compounds containing sulfo groups can be derived from the sulfo group-free compounds on which they are based Compounds caused by the action of a sulfonating agent - for example sulfuric acid monohydrate, Oleum or chlorosulfonic acid - prepare.

Coumarin compounds that contain sulfo groups bonded via an aliphatic radical are off Coumarin compounds containing oxy or amino groups by reaction with a sultone, for example with butane sultone available.

The coumarin compounds to be used as optical brightening agents according to the invention apply in the usual way, for example in the form of solutions in water or in organic Solvents or in the form of aqueous

Dispersions, including condensation products of naphthalenesulfonic acids as dispersants and formaldehyde can be used.

809 517/604

Polyester materials can be treated also in a manner with the whitening agents in that they are impregnated with solutions or dispersions of brighteners, then squeezed off, dried and a short time to over 100 ⁰ C heated. The lightening agents 5 can also be used together with detergents. Furthermore, they can also be added to spinning or casting compounds which are used to produce artificial fibers, threads, foils and other structures.

The lightening agents to be used according to the invention are very economical. They are also very lightfast and also resistant to bleach baths containing chlorite. These beneficial The coumarin compounds which have hitherto been proposed as lightening agents have properties which contain a heterocyclic radical in the 3-position, not to the same extent.

The parts given in the following examples are parts by weight.

Compared to the whitening agent of the formula obtainable according to German patent 1 090 624

25th

30th

shows the lightening agent of the general formula to be used according to the invention

the advantage of higher lightfastness on polyethylene glycol terephthalate fibers.

example 1

Polyester fibers made from terephthalic acid and glycol are used in a fiottea ratio of 1:40 Treated in a bath containing 1 g of oleyl alcohol sulfonate, 0.75 g of formic acid and 0.05 g of 3-thienyl- (2 ') - coumarin per liter contains as a lightening agent. The bath is then heated to the boil and Maintained at this temperature for 30 to 60 minutes. After rinsing and drying, the polyester fibers show an excellent brightening.

The brightening agent used according to the invention had been prepared in the following manner: 6.4 parts of 2-oxybenzaldefayd were added to a mixture of 11.7 parts of the sodium salt of thienyl-2-acetic acid and 27 parts of acetic anhydride. The reaction mixture was heated to boiling within half an hour, then refluxed for 6 hours, then cooled slightly and finally added to 500 parts of water. After several hours of stirring, the precipitate formed was filtered off with suction, washed neutral, dried and recrystallized from a mixture of alcohol and acetonitrile. The thus obtained 3-thienyl (2 ') - coumarin melted at 16g to 170 ⁰ C.

Example 2

Polyacrylonitrile fibers are introduced into an aqueous bath in a liquor ratio of 1:40 Liters 1 g of a surface-active paraffin sulfonate, 0.75 g of formic acid and 0.05 g of 3-TMenyl- (2 ') - coumarin contains as a lightening agent. The treatment bath is completed within 20 to 30 minutes heated to boiling and held at this temperature for 30 to 60 minutes. In conclusion, be the polyacrylonitrile fibers rinsed and dried. The fibers are then in an excellent manner lightened.

Example 3

Cellulose acetate fibers are ^{treated in a liquor ratio of 1:30 at 30 to 70 0} C for 20 to 30 minutes in an aqueous bath containing 1 g of oleyl alcohol sulfonate and 0.03 g of 7-acetoxy-3-thienyl- (2 ') - coumarin per liter Contains lightening agents. The fibers are then rinsed and dried. They then show a very good lightening effect.

The lightening agent used in the present invention was prepared in the following way: In a mixture of 22.8 parts of the sodium salt of Thienyl-2-acetic acid and 53 parts of acetic anhydride were introduced into 14.1 parts of 2,4-dioxybenzaldehyde. The reaction mixture was heated to boiling within half an hour, then Maintained at this temperature for 6 hours, then cooled slightly and finally to 500 parts Given water. After several hours of stirring, the precipitate formed was filtered off with suction, neutral washed, dried and recrystallized from dioxane. The 7-acetoxy-3-thienyl- (2 ') -coumarin thus obtained melted at 193 to 194 ° C.

Example 4

Cellulose acetate fibers are in a liquor ratio 1: 30 treated with 30 to 70 ⁰ C for 20 to 30 minutes in an aqueous bath containing per liter Oleylalkoholsulfonat Ig and 0.03 g 7-Phenylcarbamyloxy-3-thienyl- (2 ') - coumarin contains as a whitening agent . The fibers are then rinsed and dried. They then show a very good, greenish lightening effect.

The lightening agent used according to the invention had been prepared in the following manner: 13.0 parts of low 7-acetoxy-3-thienyl- (2 ') - cum, the preparation of which is described in Example 3, were refluxed with 100 parts of alcohol for 10 minutes . The resulting suspension was treated dropwise with 24 parts of 10% sodium hydroxide solution and then refluxed for 1 hour. The solution thus obtained was then mixed with 500 parts of water, heated to the boil, clarified with activated charcoal after the addition of 5.5 parts of 10% strength sodium hydroxide solution, then cooled and acidified with 44 parts of 10% strength hydrochloric acid. The deposited 7-oxy-3-thienyl- (2 ') - coumarin was filtered off with suction, washed with water and dried; umkristaUisiert from alcohol melted the compound at 228 to 231 ⁰ C. 8,2TeUe 7-oxy-3-thienyl- (2 ') - coumarin were then within

40

Was added for 15 minutes in 25 parts of phenyl isocyanate, the mixture was gradually heated to 150 ° C, then for 1 hour at 15O ⁰ C and then 22 hours at 100 ⁰ C stirred, then cooled to 15 ° C and mixed with 25 parts of methanol. After stirring the mixture for some time, it was cooled to 0 ° C. The precipitated 7-phenylcarbamyloxy-3-thienyl- (2 ') - coumarin was filtered off and washed with ice-cold methanol; recrystallized from dimethylformamide, the compound melted at 220 to 221 ° C.

Example 5

Polyester fibers made from terephthalic acid and glycol have a liquor ratio of 1:40 treated in a bath containing 1 g of oleyl alcohol sulfonate per liter and 0.125 g of 5,7-dichloro-3-thienyl- (2 ') -coumarin or 5,7-dimethyl-3-thienyl- (2') -coumarin contains as a lightening agent. The bath is then heated to the boil for 30 to 60 minutes held at this temperature. After rinsing and drying, the polyester fibers show a very good brightening.

The 5,7-dichloro-3-thienyl- (2 ') - coumarin was prepared in the following way: 19.1 parts of 3 were added to a mixture of 22.3 parts of the sodium salt of thienyl-2-acetic acid and 55 parts of acetic anhydride , 5-dichloro-2-oxybenzaldehyde registered. The reaction mixture was heated to the boil within half an hour, then refluxed for 6 hours, then cooled somewhat and finally added to 1000 parts of water. After several hours of stirring, the precipitate formed was filtered off with suction, washed neutral, dried and recrystallized from a mixture of dioxane and dimethylformamide. The 5,7-dichloro-3-thienyl thus obtained (2 ') - coumarin melting at 249-250 ⁰ C.

The 5,7-dimethyl-3-thienyl- (2 ') - coumarin was obtained by using 15 parts of 3,5-dimethyl-2-oxybenzaldehyde in place of the 3,5-dichloro-2-oxybenzaldehyde and the rest in the procedure described above was carried out. Recrystallized from dioxane melted the 5,7-dimethyl-3-thienyl (2 ') - coumarin at 203-204 ⁰ C.

Example 6

Cellulose acetate fibers are ^{treated in a liquor ratio of 1:30 at 30 to 70 °} C. for 20 to 30 minutes in an aqueous bath containing 1 g of oleyl alcohol sulfonate and 0.06 g of 3- [5'-bromothienyl- (2 ')] coumarin per liter contains as a lightening agent. The fibers are then rinsed and dried. , You then show a very good, green-tinged lightening effect.

The whitening agent to be used in the present invention was prepared in the following manner 17.4 parts of 2-oxybenzaldehyde and 28.7 parts of 5-bromothienyl-2-acetonitrile were in 20 parts of alcohol dissolved, and the solution was added dropwise with 3 parts of piperidine, with a slight Warming occurred. The reaction mixture was heated to the boil over 4 hours at the boiling temperature held and then cooled. The deposited methine compound of the formula

^ -Br

was sucked off; recrystallized from a mixture of dioxane and dimethylformamide, it melted at 212 to 214 ° C. 5.1 parts of this methine compound were refluxed with 50 parts of alcohol and 5 parts of concentrated hydrochloric acid for 1 hour. The suspension was cooled and the 3- [5'-bromothienyl- (2 ')] -coumarin formed was filtered off with suction, washed with water and dried. After recrystallizing twice from dioxane, the compound had a melting point of 227 to 228 ^° C.

Claims (1)

Claim: Use of fluorescent, practically colorless coumarin compounds of the general formula in which R denotes hydrogen or a lower alkyl radical, while Ri and R ₂ denote hydrogen or non-coloring substituents, where two adjacent substituents can form a fused ring, and in which m is a number from 1 to 4 and η is a number of 1 to 3 as an optical brightening agent. Considered publications:
German publication No. 1 090 624. When the application was announced, comparative samples with explanations were provided. 809 517/604 2.6SQ Bundesdruckerei Berlin