US2362915A - Process for improving the fastness to washing of dyed cellulosic textile materials - Google Patents

Description

either as such, or more Patented Nov. 14, 1944 PROCESS FOR MPROVING THE FASTNESS T WASHING OF CELLULOSIG TEX- TILE MATERIALS James Hutchison MacGr egor, Bocking, Braintree,

England, assignor to Courtaulds Limited, London, England, a British company No Drawing. Application January-23, 1942, Se-

Great Britain December rial No. 428,012. In

4 Claims.

This inventionrelates to the treatment of cellulosic textile material and in particular to improving the'fastness to washing, without greatly impairing the fastness to light or altering the original shade of the said material which has been dyed with'a direct cotton dyestuff, and at. the same time giving it. a softer silkier handle and appearance.

I have found that the fastness to washing of cellulosic textile materials dyed with direct cotton dyestuffs is improved by treating the dyed material with a solution containing formaldehyde and an arylguanidine or a guanidine salt of an aliphatic dicarboxylic'acid or. a guanidine salt of an alkyl ester of an aliphatic dicarboxylic acid,

probably in the form of, their water-soluble condensate, and then converting the mixture or the soluble condensate into an insoluble condensate, for instance by heating to a temperature of 140 centigrade in the presence of an acidcatalyst. In the case of the guanidine salts of aliphatic dicarboxylic acids and of alkyl esters of aliphatic dicarboxylic acids the condensation with formaldehyde can, if 'desired, be carried out in neutral or alkaline media. As an example of an arylguanidine which can be used according to this invention, I mention diphenylguanidine cm..NH-c'NHctHt It. v Examples of guanidine salts of aliphatic dicarboxylic acids are guanidine adipate and guanidine sebacate, while as an example of a guanidine salt of an alkyl ester of an aliphatic dicarboxylic acid I would mention the guanidine salt of ethyl adipate. The treatment can, if desired, be carried out in the presence of other water-soluble condensates such for instance as urea-formaldehyde, thiourea-formaldehyde and melamineformaldehyde.

When carrying out the process of the present invention I have found that it is desirable to avoid the use of a large excess of formaldehyde.

The following examples illustrate the invention Rigan Sky Blue G (Soc. Chem. Ind. Basle) is im-- mersed therein and after saturation the fabric is removed from the bath and squeezed evenly and is placed in a pin stenter frame and dried at just under 100 centigrade; it is then heated at 140 'centigrade for minutes. The resultant fabric has a good fastness to light, an improved fastness to washing and a soft silk-like handle and appearance.

Example 2 in 30 cubic centimetres of 80 per cent acetic acid and this solution is added to 100 grams of the urea-formaldehyde condensate prepared above and mixed with suflicient distilled water to make 1 litre of solution. A sample of an all viscose satin fabric which has been dyed with Rigan Sky Blue G is immersed therein and after soaking is removed from the solution and squeezed evenly. The fabric but they are not to be considered aslimiting it in any way.

Example! 7 30 grams of diphenilguanidine are dissolved by warming with 30 cubic-centimetres of per cent acetic acid. 160 cubic centimetres of 40 per cent formaldehyde are-added with sufllcient distilled";

water to make 1 litre of solution. A sample of an:

all viscose rayon fabric which has been dyed with at rlcis placed just under placed in a pin stenter frame and dried at just under100 centigr'ade. It is then heated at centigrade for 15 minutes to form the insoluble condensation product. During this heating a part of the formaldehyde is split off from the urea-formaldehyde condensate and combines with the diphenylguanidine. The fastness to'light and the fastness to washing of the dyed treated material are found to be improved. r

If desired, a soluble diphenylguanidine-formaldehyde condensate may be substituted for the diphenylguanidine in this example.

Example 3' 30 grams of guanidine' sebacate are dissolved in a little warm water, the resulting solution cooled, 200 cubic centimetres of 40 per cent formaldehyde added and the whole diluted with distilled water to make 1 litre of solution. The pH of the solution is then adjusted to 8.0; A sample of an all viscose satin fabric which has been dyed with Rigan Sky Blue G (Soc. of Chem. Ind. Basle) is immersed therein and after soaking is removed from the solution and squeezed evenly. I The fabin a pin stenter frame and dried at centlgrade. It is finally heated at 140 centigrade for 15 minutes \to form the insoluble condensation product. The resultant fabric possesses a soft silky handle, has very good fastness to light and is extremely fast to washing, for example when a piece of the fabric of dimensions 4" x a" and a piece of white undyed fabric of dimensions 2" .x 2" are treated in 70 cubic centimetres of a 0.2 per cent soap solution for 90 minutes at 60 centigrade, the fabrics removed and rinsed with distilled water the white piece remains unstained while the shade of the dyed piece is unchanged.

" Example 4 30 grams of guanidine adipate are dissolved in a little warm Water, the solution cooled and 200 1 cubic centimetres of 40 per cent formaldehyde added. Just before use 10 grams of ammonium sulphate dissolved in a little water are added and the whole bulked to 1 litre with distilled water.

A length of an all viscose satin fabric which has What I claim is:

1. The process of improving the fastness to washing of cellulosic textile materials dyed with direct cotton dyestuffs and imparting a soft silks, handle thereto, by treating the dyed material with a solution containing a watersoluble condensate of formaldehyde with a substance selected from the group consisting of an arylguanidine, a guanidine salt of an aliphatic dicarboxylic acid and a guanidine salt of an alkyl ester of an aliphatic dicarboxylic acid, and then converting the soluble condensate into an insoluble condensate.

2. The process of improving the fastness to washing of cellulosic textile materials dyed with direct cotton dyestuffs and imparting a soft silky handle thereto, by treating the dyed material with a solution containing formaldehyde and a. substance selected from the group consisting of an arylguanidine, a guanidine salt of an aliphatic dicarboxylic acid and a guanidine salt of an alkyl ester of an aliphatic dicarboxylic acid, and then converting the said mixture into an insoluble condensate.

8. A process as claimed in claim 1 in which the insoluble condensate is formed by heating in the presence of an acid catalyst.

4. A process as claimed in claim 2 in which the insoluble condensate is formed by heating in the presence of an acid catalyst.

. JAS. H. MACGREGOR.