SU46871A1 - Method for continuous bleaching of cotton products - Google Patents

Description

 In currently used industry methods of whitening cotton and cotton products (yarn, fabric, etc.) are more or less long {4f 10 hours) from cooking goods in an aqueous solution of hydrogen peroxide in the presence of stabilizers. An example is the Mora method and the so-called American bleaching methods, in which the processing time of a product with peroxide solution ranges from 4 (Mora method) to 6-10 hours (American methods).

 - It is also known that although acceleration of the bleaching process with hydrogen peroxide is possible under the condition of increasing the alkalinity of the solution and reducing the amount of stabilizers introduced into it, but this results in large unproductive losses of hydrogen peroxide resulting from the self-decomposition of the working solutions prepared by the above method.

The proposed method aims to accelerate the process of bleaching cotton and cotton products without loss or only with a small one. loss of hydrogen peroxide in the process itself (20)

zhenin in the baths. This is achieved by the fact that cotton or cotton products; LIA (yarn, fabric, etc.) is first soaked at general temperature with a stable (neutral or slightly acidic) hydrogen peroxide solution, after which, in an unwashed form, they are treated with hot ( 90-95 °) with a slightly alkaline solution consisting of an aqueous solution of hydrates of alkali or alkaline earth metals or alkali-reactive salts, in the presence of sludge stabilizers without them, for a short time (10-20 minutes), after which the tissue or cotton washes well First, in the mountain, and then in cold water, it is pressed and dried in the usual order.

Example 1. A perhydrol is saturated with an aqueous solution containing 31 g of hydrogen peroxide per liter, at a temperature of 15-20 °, pressed to 1000/0 of the solution content, and then treated with a hot (90-95 °) alkaline solution for 10 minutes, rinsed well first on r: rr, and then on starvation water, wrung out and in the usual order.

 The alkaline solution has approximately the following composition:

Zhdky 1 Atri 36 Vyo 7 g

Sodium silicate 38 ° Be 11.5 g

Olein-soda soap 50%. . 10 g

Waters 971.5 g

G; 00 g

The amount of alkali, its nature and the amount of stabilizers, as well as the total composition of the bath can vary to change the speed of the process and depending on the weight and quality of the goods being processed.

Due to the achieved reduction in the whitening time of cotton products using hydrogen peroxide, it becomes possible to apply this method in continuous flow methods of work both in tow and in straightening.

The following technological processes can serve as an example of whitening of goods in a harness:

Example 2. The fabric is impregnated on a Klapo-type material machine with an aqueous solution of hydrogen peroxide in the presence of wetting agents (31 g of hydrogen peroxide and 10 g of neutralized contact in 1 liter of water) at a temperature of 15-20 ° C and the corresponding spin.

2. The impregnated fabric is processed on a material machine of the Matezius type for 15–20 minutes with a hot (90–95 °) alkaline solution containing in a liter:

Caustic soda 39 ° Be .7 g

Silicate 58 ° Be 11.5 g

Olein-sodium soap 50%. . .South

3-4. The fabric is washed on two mlaine machines of the type Klapo on hot water at a temperature of 60-65 °.

5. Additional rinsing of fabric on a cold-washing machine of the English type.

6.Otzhim tissue on the squat or water calender.

When MB is p 3. The fabric is bleached for smooth dyeing and for responsible underwear and printed grades as follows: 1. The fabric is processed for 45 minutes in a Martesius-type apparatus with hot (85-95 °) alkaline emulsifying solution containing 10- 15 g of sodium hydroxide in 1 liter, or an emulsifier, for example, 5-10 g of contact, bisulphate and sodium 36 Vy from 7.5 to 11.5 g in a liter and liquid silicate from 4 to 7.5 in a liter.

2-3. The fabric is washed in hot water (60--70 °) on two washing machines of the Clapo type.

4. The fabric is washed in juice water in an English type washing machine .:

5.Otzhim fabrics on the squeezer.

6. Impregnation of the fabric on a Klapo-type material machine with an aqueous solution of hydrogen pernoxide (31 g of hydrogen peroxide in a liter) at a temperature of 15-20 ° C with the appropriate spin.

7. Treatment of the impregnated fabric on a material machine of the Matezius type for 10–15 minutes with a hot (90–95 °) alkaline solution containing in a liter:

Caustic Sodium 36 ° Be 7 e

Silicate 38 ° Wy. .11.5 g

Slenic-sodium 50% soap ... South

8-9. Washing the cloth on two Klapo-type washing machines on hot water at a temperature of 60-65 °.

10. Wash the fabric in the English washing machine with cold water.

11. Pressing the fabric on a squander or water calender.

The described processes, if necessary, can also be developed in a spacer, and the equipment described above is replaced by a) for impregnation with a hydrogen peroxide solution — plus with a drawer, b) and for other material processes, a material machine working like a Zittaus plant and c) for washing-washing and short devices of the usual type.

The subject matter of the invention.

1. A method of continuous bleaching of cotton products with the use of sequential treatment with hydrogen peroxide solutions and alkalis, characterized in that boiled or not boiled fabric impregnated with hydrogen peroxide solution is subjected to treatment with hot weak

hydrates of alkali or alkaline-earth metals or aqueous solutions of alkali-reactive salts, such as soda, silicate, fatty or resin soaps, - / neutralized eulfonaphthenic acids, etc.

the presence of stabilizers and neutral salts or without them.

2. Acceptance of the method indicated in paragraph 1., characterized in that the alkaline treatment of the fabric is carried out at 90-95 ° for 10-20 minutes.