DE1103882B - Process for bleaching all types of textile goods - Google Patents

Description

Process for bleaching textile goods of all types It is known peroxidic Compounds, for example hydrogen peroxide, sodium peroxide, N sodium perborate and the like. To be used as detergents and bleaching agents for fibrous materials of all kinds. In in some cases difficulties arise in their application, since one is proportionate must need high temperatures in order to achieve the desired bleaching effect.

A number of so-called activators have therefore been proposed the addition of which has a bleaching effect on the peroxidic compounds allows lower temperatures. These activators include, for example, formamide, Amides of unsaturated lower carboxylic acids, organic nitriles, anhydrides di- or polybasic carboxylic acids. Anhydrides of low molecular weight carboxylic acids or such Halogen derivatives of low molecular weight carboxylic acids, which are formed into carboxylic acids by hydrolysis or their salts can be transformed.

It is also known to use bleach liquors containing peroxides as stabilizers Magnesium salts of the polymers of acrylic acid or metharyl acid in a mixture with Add magnesium silicates.

It has now been found that activators for peroxidic compounds the anhydrides of lower α, ß-unsaturated monocarboxylic acids with excellent success let use. Examples include acrylic anhydride and methacrylic anhydride or called crotonic anhydride. The addition of these substances already takes place at essential excellent bleaching takes place at a lower temperature.

It has also been found that even with relatively small Quantities of activators. It is preferred to use per mole of active oxygen, calculated as H 2 O 2, 0.1 to 1.0 moles of the activator.

To a polymerization and thus an ineffectiveness of the unsaturated To avoid acid anhydrides, a polymerization inhibitor can be added to the solutions in some cases be admitted.

The bleach liquors, which peroxide compounds and those according to the invention Contain activators, stabilizers, buffer substances, Wetting agents, detergent substances, fiber protection agents and optical brightening agents can be added. Especially oxalic acid and have proven to be stabilizing additives Oxalates well proven.

The best effects will be with bleach liquors according to the invention achieved in neutral, weakly acidic or weakly alkaline areas.

For the activators to work, it is necessary that they be in dissolved state. This can also be achieved by being in water poorly soluble activators first in a water-soluble organic solvent dissolves and then adds this solution to the bleaching liquor.

Example 1 A cellulose tissue boiled with red wine is examined, that in the Zeiss-Elrepho whiteness meter against white standard 565 with filter 6 a white value of 37.9% shows 0.

This fabric is treated with a liquor at 65 ° C for 30 minutes, the following substances per liter contains 2.50 g dodecyl sulfate, 1.25 g sodium pyrophosphate, 1.25 g sodium tripolyphosphate, 1.20 g sodium perborate, 0.577 g methacrylic anhydride, 0.50 g oxalic acid.

The pH of the solution is 7.0. The treated fabric is rinsed, dried, after which a whiteness of 70.1 0 / a is determined.

One under otherwise the same conditions, but in the absence of methacrylic anhydride treated fabric has a whiteness of only 50.8% - and is still pale pink colored.

Example 2 A fabric is made according to the method described in Example 1 treated with a liquor that contains the following substances per liter: 2.50 g dodecyl sulfate, 1.25 g sodium pyrophosphate, 1.25 g sodium tripolyphosphate, 1.20 g sodium perborate, 0.473 g acrylic anhydride (stabilized with 0.2% hydroquinone), 0.50 g oxalic acid.

The pH of the solution is 7.0. The fabric is given a degree of whiteness of 69.0 0/0, while without the addition of acrylic anhydride a degree of whiteness of only 50.8 % is obtained.

Example 3 According to Example 1, a fabric is treated with a liquor which contains the following substances per liter: 2.50 g dodecyl sulfate , 1.25 g sodium pyrophosphate, 1.25 g sodium tripolyphosphate, 1.20 g sodium perborate, 0.577 g crotonic anhydride (freshly distilled Product), 0.55 g oxalic acid.

The p11 value of the fleet is 6.8. After the treatment is the whiteness 68.1%, while without crotonic anhydride a degree of whiteness of only 50.8% is achieved.

Example 4 A desized cotton poplin fabric is made at 70 ° C and pH 5.3 bleached for 1 hour in the following way: To prepare the bath 10 ccm of hydrogen peroxide, 35% strength = 0.113 mol, 2 g of sodium pyrophosphate and 1.6 cc sodium hydroxide solution at 38 ° Be by pouring 50 to 100 cc water over it at 60 Dissolved up to 70 ° C. and added 3.48 g of methacrylic anhydride = 0.0226 mol.

It is stirred until solution has occurred. After that, this basic approach is used diluted to 1 liter with 70 ° C warm water. In this bleach bath 50 g of the above Fabric bleached for 1 hour with very gentle agitation.

After rinsing and drying, the result is a degree of whiteness of. 79.5 0/0 (Elrepho: white standard 565, filter 6).

Claims (5)

PATENT CLAIMS: 1. Process for bleaching textile goods of all kinds with aqueous liquors of peroxide compounds, characterized in that one of the bleaching liquor anhydrides of a, ß-unsaturated monocarboxylic acids as activators incorporated. 2. The method according to claim 1, characterized in that one per mole active oxygen, calculated as H 2 O 2, used 0.1 to 1.0 mol of the activator. 3. The method according to claim 1 or 2, characterized by the use of liquors, which also contain a polymerization inhibitor. 4. Procedure after a of claims 1 to 3, characterized in that one in neutral, weakly acidic or weakly alkaline area. 5. The method according to any one of the claims 1 to 4, characterized by the use of a liquor which is small amounts of water-soluble contains organic solvent. Publications considered: German U.S. Patent No. 848,071; German interpretation document H 24402 IVa / 23 e (published on November 22, 1956).