GB1589397A

GB1589397A - Process for dyeing or printing polyester or polyamide fibres

Info

Publication number: GB1589397A
Application number: GB4207277A
Authority: GB
Original assignee: Hoechst AG
Current assignee: Hoechst AG
Priority date: 1977-10-10
Filing date: 1977-10-10
Publication date: 1981-05-13

Description

(54) PROCESS FOR DYEING OR PRINTING POLYESTER OR POLYAMIDE FIBRES (71) We, HOECHST AKTIENGESELLSCHAFT, a body corporate organised according to the laws of the Federal Republic of Gennany, of 6230 Frankfurt/Main 80, Postfach 80 03 20, Federal Republic of Germany, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: The present invention relates to the dyeing and printing of polyester and polyamide fibres.

German Auslegeschrift No. 24 33 662 discloses a process for the dyeing and finishing of textile goods in which the textile goods are impregnated with dyestuff and are exposed to methylene chloride. By this process for textile goods comprising polyester fibres, the dyestuff and/or the application agent are applied in an aqueous solution or dispersion onto the textile goods, which are then exposed to an air current which is enriched with methylene chloride. The advantage of this method is that it provides a dyeing process at a temperature of from room temperature up to a maximum temperature of 30"C under atmospheric pressure. In this process only gaseous methylene chloride is used, which involves certain problems with regard to the toxicity of methylene chloride.According to the state of the art, a relatively long dwelling time is partly required in the after-treatment.

Our co-pending Patent Application No. 42071/77 (Serial No. 1 576 952) (Case HOE 77/F 055) discloses and claims a process for dyeing or printing polyester or polyamide fibres or filaments or a material consisting of or containing polyester or polyamide fibres or filaments, which comprises (a) applying an aqueous liquor or printing paste containing a dispersion dyestuff to the fibres, filaments or material, and optionally then drying the fibres, filaments or material, (b) condensing methylene chloride onto the fibres, filaments or material, and (c) allowing the fibres, filaments or material to dwell, preferably at room temperature, for fixation of the dyestuff under conditions such that the fibres, filaments or material remain moist with methylene chloride.

The present invention provides a modlfication of this process, wherein the methylene chloride is applied in liquid form to the fibres, filaments or material (step (b)) by spraying, sprinkling, foaming, padding or by means of rollers or brushes.

In accordance with the process of the invention all water-insoluble dispersion dyestuffs, either singly or as mixtures of two or more thereof, may be used. The dyestuffs of this kind generally belong to the azo, anthraquinone, quinophthalone or benzthioxanthene dyestuff series, the azo dyestuffs being in metallized or metal-free form. Dyestuffs of the above-mentioned categories are well known and are described in the COLOUR INDEX, third edition (1971), volume 2 under the classification "Disperse Dyes".

By the process of the invention dyeings may be obtained which are equal or even superior to those obtained by more expensive processes with regard to the apparatus and the energy required, for example the thermosoling or the high-temperature processes, as far as the dyestuff utilization and/or the colour depth and fastness properties are concerned.

The application of the methylene chloride is preferably effected by means of a padding method or by applying with rollers (for example by slop-padding).

The polyester fibres which may be dyed or printed by the process according to the invention may, for example, be: polyethylene terephthalate, polycyclohexane-dimethylene terephthalate, heterogeneous polyesters, for example those of terephthalic acid, isophthalic acid and ethylene glycol or those of sulfo-isophthalic acid and ethylene glycol, furthermore copolyether esters of p-hydroxybenzoic acid, terephthalic acid and ethylene glycol, and polycarhonates. According to the process of the invention it is also possible to dye or print those polyester fibres which can be dyed at boiling temperature without carriers. Polyester fibres of this kind may be obtained, for example, by incorporating aliphatic dicarboxylic acids, for example adipic acid, or diol compounds having a longer chain, for example as in polybutylene terephthalate.

The process of the invention is suitable for the dyeing or printing of any of the usual synthetic polyamide fibre materials.

The dwelling temperature is normally 10 to 20"C below the boiling point of methylene chloride; however, in units that have been designed correspondingly, it may also reach the boiling point or be above this temperature.

Normally room temperature is applied, but temperatures of 0 C or below are also possible.

The process of the invention may be carried out in such a way that for the dwelling period sheets which may be permeable or impermeable to methylene chloride are inserted between material parts in contact with one another. The sheets are merely to prevent smudging from one part of the material to another, which is especially important in the case of multi-colour effects or prints.

While it is known as indicated ahove thai for dyeing and finishing textile material comprising polyester fibres, the material may be exposed to an air current enriched with gaseous methylene chloride following impregnation with an aqueous dyestuff solution or dispersion, it is surprising that the process of the invention is successful, since it would be expected that the moistening of the material with methylene chloride would lead to a bleeding of the dyestuff and thus to an uneven dyeing or printing, especially as an uneven bleeding was to be expected due to the additional moistening process.

Compared with the application of the methylene chloride by condensation according to our co-pending Patent Application No. 42071/77, (Serial No. 1576 952) the application methods according to the process of the invention have the advantage that they generally require only minor expenditure with regard to time and apparatus.

The dwelling, preferably in a wound-up state, may be effected within or outside a chamber. The dwelling step may also be carried out discontinuously or continuously by cuttling up the material on screen belt conveying units. The dwelling may also be effected in a different manner, for example, in festoon dwelling units.

The dyestuff impregnation liquors or printing pastes to be applied in the process of the invention are well known, and the impregnatlon, especially padding, and printing processes are carried out in accordance with known methods. For mixed-fibre fabrics, single-bath and two-bath continuous and discontinuous processes may be applied, which are known for mixed materials of this kind. The dyestuffs to be used for the nonpolyester or non-polyamide accompanying fibres are known. Thus, for example, the following embodiment falls within the invention A flat textile material comprising polyester and cellulose fibres is padded with an aqueous bath which contains a disperse dyestuff, a reactive dyestuff, an alkali and, optionally, a dispersing agent, wetting agent, electrolyte and/or thickening agent.The material is then sprayed with methylene chloride and is wound into a skein, which is allowed to dwell overnight, for example, while being turned slowly. After rinsing, soaping and drying, a dyed textile material is obtained which shows excellent properties.

Whereas in a printing process the material is preferably dried between application of the dyestuff and application of the methylene chloride, this additional process step is generally not necessary in a dyeing process.

It is surprising that, by the process of the invention, a considerably greater number of dispersion dyestuffs may be used for the dyeing of polyester fibres than can be used according to the above-mentioned prior-art process.

The methods and/or the apparatus for spraying, sprinkling, foaming, padding or applying by means of rollers or brushes, which are required for the application of the methylene chloride, are well known and are described in the literature.

The following Examples illustrate the invention.

EXAMPLE 1.

A fabric of texturized polyester fibres was padded on a padder at room temperature, with a liquor pick-up of 90 XÓ, with an aqueous bath which contained, per litre, 20 g ot the yellow dyestuff of the formula

and 1 g of a commercial wetting agent. Subsequently, the wet padding was slop-padded with methylene chloride and was wound up. Then the wound-up material was allowed to dwell at room temperature for 3 hours while being covered, for example with a PVC sheet, the skein being turned slowly.

Following a usual after-treatment a yellow dyeing was obtained which had fastness properties of such a quality as had otherwise only been possible according to the thermosoling or high-temperature dyeing process.

EXAMPLES 2 to 8.

Similar good results were obtained when the process of Example 1 was carried out but using, instead of the specified dyestuff, 20 g per litre of the dyestuffs of the following formulae:

(Yellow dyestuff) ( Blue dyestuff) (Orange dyestuff)

(Red dyestuff) (range dyestuff) (Blue dyestuff)

(Violet dyestuff)

Claims

WHAT WE CLAIM IS:-

1. A process for dyeing or printing polyester or polyamide fibres or filaments or a material consisting of or containing polyester or polyamide fibres or filaments, which comprises (a) applying an aqueous liquor or printing paste containing a disperse dyestuff to the fibres, filaments or material, (b) applying methylene chloride to the fibres, filaments or material by spraying,.

sprinkling, foaming, padding or by means of rollers or brushes, and (c) allowing the fibres, filaments or material to dwell for fixation of the dyestuff under conditions such that the fibres, filaments or material remain moist with methylene chloride.

2. A process as claimed in claim 1, wherein the methylene chloride is applied by a padding method or by means of rollers.

3. A process as claimed in claim 2, wherein the methylene chloride is applied by a slop-padding process.

4. A process as claimed in any one of claims 1 to 3, wherein the dwelling is carried out at room temperature.

5. A process as claimed in any one of claims 1 to 4, wherein the fibres, filaments or material are dried between the application of the dyestuff and the application of methylene chloride.

6. A process as claimed in any one of claims 1 to 5, wherein the fibres, filaments or material are dwelled in a wound up state.

7. A process as claimed in claim 6, wherein the fibres, filaments or material, after application of methylene chloride, are introduced into a chamber and are wound up and dwelled therein.

8. A process as claimed in any one of claims 1 to 7, wherein a sheet comprising a material that is permeable or impermeable to methylene chloride is positioned between contacting fibre, filament or material layers during dwelling.

9. A process as claimed in any one of claims 1 to 8, wherein a material which also contains cellulose fibres is dyed or printed and the aqueous liquor or printing paste also contains a reactive dyestuff.

10. A dyeing process as claimed in any one of claims 1 to 9, wherein the aqueous dyestuff liquor is applied by a padding method.

11. A process as claimed in claim 1, conducted substantially as described herein.

12. A process as claimed in claim 1, conducted substantially as described in any one of the Examples.

13. Polyester or polyamide fibres or filaments or a material consisting of or containing polyester or polyamide fibres or filaments, whenever dyed or printed by a process as claimed in any one of claims 1 to 12.