DE2204143A1 - METHOD OF WASHING TEXTILE MATERIAL - Google Patents

Description

The invention relates to a method for washing textile materials and in particular to a method for combined Washing and bleaching of textile materials and especially of natural cellulose fibers, such as. B. Cotton, Flax and jute and animal pas such as B. wool, and optionally mixed with semi-synthetic or fully synthetic fibers.

It is a natural property of cellulose fibers or animal fibers that they contain significant amounts of contaminants exhibit in the raw state. These impurities must depend on the required degree of purity of the end product removed to varying degrees.

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100 % cotton contains ζ. B. the following natural impurities, which can be divided into three groups:

1. Complex waxes and proteins

2. Colored organic matter

3. Wood components (parts of the seed pods)

In addition, when sizing (or sizing) yarn, waxy oils are usually added to the adhesive sizing agent are added and such fatty bodies can usually only be removed with great difficulty.

When using the method according to the invention posed It turns out that in many cases separate prior desizing is not necessary.

In order to remove the three types of contamination mentioned above, the textile material has conventionally been used with a strong alkali such as B. with sodium hydroxide, washed and then a subsequent bleaching operation with a Oxidizing agents, such as. B. with sodium hypochlorite, hydrogen peroxide or sodium chloride or a combination of such Oxidizing agents subjected in a certain order.

The primary purpose of alkali washing is to swell the fibers and woody contaminants

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and to saponify and emulsify the wax-like ingredients, so that in the wake of a subsequent washing operation the textile material can be effectively bleached.

There are already known and customary one-step processes which combine the washing process and the bleaching process. However, for a 100 % cotton material, it has been found most effective in all respects to use a separate wash operation with sodium hydroxide.

One specific problem that the present method is particularly concerned with relates to processing of blends of cotton and synthetic polyester fibers in the form of fabrics.

In such blends, the cotton component is usually of good quality, well carded or combed for the best possible mechanical removal of wood-like impurities. The presence of water-like impurities and the possible presence of spinning oils in the polyester component, however, have presented considerable difficulties up to now and make it difficult and expensive to find a material with adequate absorption capacity for later operations, such as B. to create dyeing or printing.

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When processing in conventional plants and according to the normal cotton process, the sodium hydroxide can only be used in low concentrations, since there is a considerable risk of hydrolysis on the polyester component can take place. This leads to an unacceptable reduction in the tensile strength of the textile material as a whole.

In order to achieve a good absorption capacity and a uniform degree of whiteness of such blending substances, in Recently, either of the following two techniques has been used industrially.

a) A two-stage washing and bleaching process in continuously operating open wide apparatus, whereby at temperatures is worked, which are equivalent to the temperature of a saturated steam at 2 to 3 atmospheres and where Sodium hydroxide is used in the first stage and alkaline peroxide in the second stage. Allowed with this procedure the short treatment time of the order of 120 seconds a good washing and bleaching of the cotton components without material degradation of the polyester component.

b) A two-stage washing and bleaching process in a continuously operating open wide apparatus, the Washing is done with a solvent degreasing technique. This is trichlorethylene or perchlorethylene applied. The alkaline peroxide bleaching step is then carried out according to method (a).

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Both of these methods require a large amount of capital and space, and thus it is a task the present invention to provide a method wherein the three types of contaminants can be effectively removed in a one-step process.

The present invention is not limited to textile materials in the form of fabrics, but can also be used in plants for processing yarns or fabrics and yarns. It has now been found that the distance the aforementioned impurities effectively in a one-step process in a high temperature flash bleaching process can be carried out by adding a high-boiling organic solvent to the bleaching liquor or more high-boiling organic solvents together with the emulsifier and / or the surfactant. added and by also modifying the normal bleaching liquor with regard to the alkali content.

According to the invention you can, for. B. a fabric made of a polyester / cotton blend in a washing / bleaching liquor soak the following composition:

Hydrogen peroxide
Stabilizers
Alkali hydroxide
Organic solvent
Emulsifier
Surface active agent

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Suitable solvents are e.g. B. turpentine oil substitute or ^{white spirit or kerosene and suitable emulsifiers 7} or surface-active agents are marketed under the name SOVATEX by Standard Chemicals or Honeywill Atlas Products.

The soaked cloth is then squeezed out to remove excess liquor and the material becomes 90-180 Seconds with saturated steam at a temperature equivalent to a pressure of 2-3 atmospheres. The cloth is then washed and bleached well and is now ready for drying or other processing.

A preferred apparatus for carrying out the high-temperature treatment will be described below:

a) a pressure chamber

b) Static lip seals for the pressure chamber inlet and the pressure chamber outlet

c) Direct entrance to the pressure chamber without a rewetting bath after the impregnation device and before the seal

d) no rewetting by chemical treatment while the cloth is in the pressure chamber

e) a tissue collecting device within a single chamber for effecting a minimum residence time within the chamber of 90 seconds at an operating speed of 90 meters per minute, with the cloth is kept in a relaxed state.

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Each of these equipment features is known per se to the person skilled in the art of textile treatment and is therefore known a graphic representation and a detailed explanation is not required. The exact composition The bleach liquor can be varied depending on the type of cloth and the desired result. It was, however found that the ratio of solvent / emulsifier to surfactant is preferably between 3 percent by weight and is 12 percent by weight based on the textile material to be treated.

In the 100% solvent washing process described, it is necessary to use a solvent recovery system in order to make the process economical, even though the solvent loss is on the order of 5 % . It can thus be seen that the method according to the invention, in addition to reducing a two-stage process to a one-stage process, offers further work advantages.

If a bleaching process is not considered necessary, an improved washing process can also be used according to the invention in view of the degree of wettability of the mentioned cloth or yarn can be created by using the Leaves hydrogen peroxide and the stabilizers from the treatment liquor.

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In the following the invention is illustrated by means of embodiments explained in more detail.

example 1

Single-stage washing and bleaching process in an open wide apparatus. A poplin fabric with a 65/35 polyester / cotton blend is used. The basis weight is 135 g / m "".

The fabric is impregnated with the following liquor in an open wide apparatus in the raw state:

Hydrogen peroxide (35 %) 3.5 % v / v

Stabilizer sodium silicate (Q 79) 2.0 % w / v sodium hydroxide 0.7 % w / v

Sequestering EDTA (ethylenediamine 0.3 % vol / vol medium tetraacetic acid)

Emulsion solvent / surfactant 10.0 % vol / vol

A hydrocarbon type solvent is emulsified with a nonionic / anionic surfactant. Soaking bath at 20 ⁰ C.

After soaking and squeezing to a wet content of about 80.0 % , the fabric is sent through a static lip seal into a pressure reaction chamber which is filled with saturated steam at an overpressure of 30.0 0.07 kg.cm.

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The treatment is carried out at a speed of 5 ^ * 5 m / min. A residence time of 60 to 180 seconds in the chamber is selected during the process. The cloth then leaves the reaction chamber through another static lip seal and is washed in an open wide washing machine with three compartments. The first washing compartment contains water with a temperature of 90 C. The second washing compartment contains water at 6o ° C and the third washing compartment water at 20 ⁰ C. After leaving the washing apparatus through a nip, the cloth is dried and hence it is for the subsequent Editing ready.

Laboratory tests of the treated cloth show a wettability of 0.5 seconds, measured according to the AATCC »method, and a reflection value of 86.0%, measured with the Evans Electrosolenium Comparator with a magnesium carbonate standard of 88.0 %.

Example 2

Pre-wash followed by open-width washing and bleaching processing. It will be a 100 % cotton poplin

2 cloth processed. The weight per unit area is 135g / m.

Washing alone

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The cloth is impregnated with the following liquor in an open wide impregnation machine in the raw state of the chair:

Sodium hydroxide 7.0 % w / v

Solvent / surfactant 10.0 % v / v agent emulsion

It will be a hydrocarbon solvent with a non-tonic, anionic surfactants.

Soaking bath temperature 3O ⁰ C.
Surface speed 63.5 m / min.

After soaking and squeezing to a wet content of about 8θ, Ο % , the cloth is passed through a static lip seal into a pressure reaction chamber, which is saturated with steam

p with an overpressure of 30.0 0.07 kg / cm ". The cloth is then left in the reaction chamber on a transport roller with variable speed for a period of λ'οη 120 seconds and then leaves the chamber through a further static lip seal and is finally washed in a wide washing machine with three compartments The first compartment contains water at a temperature of 90 C, the second water at 60 ° C and the third water at 20 C. Finally, the squeeze on the washing machine achieves a wet content of about 6θ, Ο %.

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Washing and bleaching

The cloth is in the described condition after completion of the washing process in an open wide impregnation apparatus treated with the following bleaching liquor at a speed of 63.5 m / min:

Hydrogen peroxide (35 J ^) 2.5 % vol / vol

Stabilizer sodium silicate (079) 2.0 % w / v

Sodium hydroxide 0.2 % w / v

Sequestering EDTA (ethylenediamine 0.1 %. Vol / vol medium tetraacetic acid)

Soaking bath temperature: 20 ° C.

After soaking and checking for a wet content of about 80.0 % , the cloth is sent through a reaction chamber and washed precisely in the first stage. The cloth is then dried and is ready for further processing.

Laboratory tests on the cloth obtained show a wettability of 0.4 seconds, measured according to the AATCC method and a reflection value of 90.0%, measured with the Evans Electrosolenium Comparator with a magnesium carbonate standard of 86.0 %. The seed clearance is good and the residual fat and wax content is 0.2 %.

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A woolen worsted cloth with a basis weight of

371 g / m "is a one-step washing and bleaching process subjected. The cloth is in a raw state in a open wide impregnation machine impregnated with the following liquor:

Hydrogen Peroxide ($ 35) 4.5 % vol / vol

Sodium silicate (Q79) 1.6 % w / v

Sodium di-hydrogen phosphate 0.15 % w / v solvent / surfactant

Hydrocarbon solvent emulsified by a nonionic / anionic surfactant 10.0 % vol / vol

Bath temperature 30 C.

After saturation and squeezing to a wet content of 110 % , the cloth is passed through a static lip seal into a pressure reaction chamber, which saturated

Contains steam at an overpressure of 30.0 χ 0.07 kg / cm. The cloth is held in the chamber for 130 seconds. It then leaves the chamber through another static lip seal and is then subjected to a washing treatment according to ' Subjected to Examples 1 and 2 before drying.

Laboratory tests on the treated wipe show that 79 * 0 % of the solvent extractable material was removed.

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The white shade achieved has a value that is accepted by the trade for this material. The alkali solubility and the content of residual fat and wax are comparable to the corresponding values that can be achieved with a conventional method.

All information and features contained in the documents are claimed as essential to the invention insofar as they are individually or in combination are new compared to the state of the art.

Claims

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Claims (7)

Claims 1. A method for washing textile material, characterized in that the textile material with a liquor of sodium hydroxide and a solvent / surfactant emulsion is impregnated. 2. The method according to claim 1, characterized in that the solvent is a hydrocarbon which is emulsified with a nonionic / anionic surfactant is used. 3 · Method according to one of claims 1 or> 2, characterized characterized in that the ratio of solvent / emulsifier / surfactant Means between 3 percent by weight and 12 percent by weight, based on the to treating textile material, is chosen. 4. The method according to any one of claims 1 to 35, characterized characterized in that a liquor is used for the simultaneous implementation of the bleaching, which in addition Contains hydrogen peroxide, a stabilizer and a sequestering agent. 5. The method according to claim 4, characterized in that sodium silicate is used as a stabilizer. - 15 309831/1077 - ¹⁵ - 2204U3 6. The method according to any one of spoke 4 or 5> characterized in that fttliylenediamine-tetraacetic acid is used as the sequestering agent. 7. The method according to any one of claims 1 to 6, characterized in that the impregnated textile material is squeezed and subjected to saturated steam in a pressure vessel for 60 to 180 seconds and then washed and dried. 309831/1077