Emulsions

Abstract

Stabilised emulsions in halogenated hydrocarbon solvents of aqueous solutions or dispersions of dyestuffs or textile finishing agents, in which the emulsifying agents present comprise ethyl hydroxyethyl cellulose and one or more anionic surface-active agents. Also treatment of textile materials with such stabilised emulsions.

Description

This invention relates to improved emulsions in halogenated hydrocarbon solvents of dyestuffs and textile finishing agents, and to the use of such emulsions in the dyeing and finishing of textile fabrics.

It is known to apply dyestuffs and finishing agents to textile materials with the aid of organic solvents, such as halogenated hydrocarbons. Such methods of application have been developed as an alternative to the conventional procedures utilising aqueous media, for reasons of economy, conservation of water supplies or avoidance of effluent problems. The range of dyestuffs or finishing agents which are adequately soluble in such solvents is, however, limited, and it is usually necessary to employ the dyestuff or finishing agent in the form of a dispersion or emulsion in the solvent. One method of obtaining such dispersions or emulsions which has been proposed consists in preparing an aqueous solution or dispersion in the organic solvent with the aid of a suitable emulsifying agent.

It has now been found that a combination of ethyl hydroxyethyl cellulose with an anionic surface-active agent is of particular value for use as such an emulsifying agent.

According to the present invention there is provided a stabilised emulsion in a halogenated hydrocarbon solvent of an aqueous solution or an aqueous dispersion of a dyestuff or a textile finishing agent, characterised in that the emulsion contains as emulsifying agents ethyl hydroxyethyl cellulose and at least one anionic surface active agent.

By `ethyl hydroxyethyl cellulose` is meant a mixed cellulose ether which is prepared by a process involving the following three reactions :

1. alkali cellulose formation in which cellulose is swollen by aqueous sodium hydroxide; Cell - OH + NaOH.revreaction.Cell - OH.NaOH;

2. reaction of cellulose with ethylene oxide in the presence of alkali : Cell - OH +, ##SPC1##

.sup.naOH Cell - OCH.sub.2 CH.sub.2 OH

3. ethylation of cellulose and hydroxyethyl cellulose:

(a) Cell - OCH.sub.2 CH.sub.2 OH + NaOH + C.sub.2 H.sub.5 Cl .fwdarw. Cell - O CH.sub.2 CH.sub.2 OC.sub.2 H.sub.5 + NaCl + H.sub.2 O

(b) Cell - OH + NaOH + C.sub.2 H.sub.5 Cl.fwdarw.Cell - OC.sub.2 H.sub.5 +NaCl + H.sub.2 O

Ethy hydroxyethyl cellulose may thus be defined as cellulose in which most of the hydroxyl groups have been converted to ethyl ether groups or ethoxyethyl ether groups. Ethyl hydroxyethyl cellulose is available commercially in a number of different grades depending on its molecular weight. These grades may be characterised by their solution viscosities, ranging from 10 to 250 cp. as measured on a 5% solution by weight of the ethylhydroxyethyl cellulose in a mixture of 80 : 20 (by weight) toluene/ethanol. Any grade of ethyl hydroxyethyl cellulose is suitable for use in the emulsions of the present invention, but the grade having a solution viscosity as hereinbefore defined of 20 - 35 cp is preferred.

Anionic surface active agents which are suitable for use in the emulsions of the invention include salts of sulphonated castor oil, known collectively commercially as Turkey Red Oil, salts of sulphated methyl oleate, salts of dodecylbenzene sulphonic acid, salts of oleic acid and linoleic acid, salts of tall oil, salts of sulphated mixtures of oleyl and cetyl alcohols and salts of oleyl-p-anisidide sulphonic acid and oleyl sarcoside, more particularly the sodium salts thereof. Either a single anionic surface active agent or a mixture of two or more such agents may be employed.

Halogenated hydrocarbon solvents which may be employed in the emulsions of the invention include trichloroethylene, perchloroethylene, 1:1:1:-trichloroethane, carbon tetrachloride, chloroform, monochlorobenzene and 1:2:4-trichlorobenzene.

Dyestuffs which may be incorporated in the emulsions of the invention include any of the well-known classes, for example acid, basic, direct, reactive or disperse dyestuffs as conventionally employed for the dyeing of textile materials composed of polyamide, cotton, wool, silk, acetate, polyester, viscose or acrylic fibres or filaments.

Textile finishing agents which may be incorporated in the emulsions of the invention include fluorescent optical brightening agents, such as the sodium salts of bis-triazinyl-aminostilbene di-sulphonic acids, water-proofing agents such as stearamidomethylpyridinium chloride and N-methylolstearamide, crease-resist resins such as dimethyloldihydroxy-ethylene urea, antistatic and antisoil/soil release agents such as condensates of ethylene oxide with polyamides, crystallisable polyesters containing polyoxyalkylene groups, for example polyoxyalkylene terephthalate/polyalkylene terephthalate block copolymers and copolymers of polymerisable acids, for example acrylic acid, with other polymerisable vinyl monomers, softening agents such as fatty quaternary ammonium salts, desizing agents such as enzyme preparations, flameproofing or flame retarding agents such as antimony trioxide or mixtures of boric acid and borax.

The emulsions of the present invention may be produced by subjecting a mixture of a halogenated hydrocarbon solvent and an aqueous solution or dispersion of a dyestuff or textile finishing agent to suitable mechanical agitation in the presence of ethyl hydroxyethyl cellulose and at least one anionic surface-active agent.

The emulsifying agents used, that is to say the ethyl hydroxyethyl cellulose and the anionic agent or agents, may be initially present in either the halogenated hydrocarbon solvent or the aqueous solution or dispersion of the dyestuff or finishing agent, or both. However, having regard to the solubility properties of ethyl hydroxyethyl cellulose,in particular the 20 - 35 cp. grade which is preferred for use in the present invention, it will usually be convenient for this constituent to be dissolved initially in the halogenated hydrocarbon solvent. The anionic agent or agents may be dissolved initially in either the solvent phase or the aqueous phase, but if desired, in accordance with a well-known technique of emulsification using such agents, it may be produced in situ by reaction between a suitable organic acid precursor, for example dodecylbenzene-sulphonic acid, dissolved in the halogenated hydrocarbon solvent phase and an alkali, for example sodium hydroxide, dissolved in the aqueous phase.

The relative proportions of the halogenated hydrocarbon solvent and the aqueous phase incorporated in the emulsions of the invention may vary widely, according to the manner in which the emulsions are to be applied to the textile fabric and to the type and solubility of the dyestuffs or finishing agents employed. Commonly, however, the amount of water will lie in the range 0.3 to 20.0% of the total weight of the emulsion.

The emulsions of the present invention are valuable for the application to textile materials of the dyestuffs or finishing agents which they contain. In general, the emulsions may be applied to the textile materials by passing, exhaustion or any other conventional form of impregnation, followed by evaporation of the halogenated hydrocarbon solvent and, if necessary, a final baking operation to fix the dyestuff or finishing agent on the textile material. The halogenated hydrocarbon solvent which is evaporated during this process may, of course, be recovered for re-use.

Textile materials to which the emulsions of the invention may be applied include yarns and knitted, woven or non-woven fabrics.

The use of the emulsions of the invention instead of conventional aqueous solutions or dispersions of dyestuffs or textile finishing agents confers a number of advantages. Exhaustion may be more rapid in batchwise processes and wetting out easier and pick-up better in padding procedures. Losses in dimensional stability are reduced. The halogenated hydrocarbon solvents have lower specific heats and latent heats of evaporation than water, thus reducing costs of heating and drying and also permitting economic recovery of the organic liquid for reuse which avoids the increasingly severe difficulties being met in the treatment of aqueous effluents. A number of finishing treatments, and also dry cleaning of textile materials, are carried out in non-aqueous media and in suitable cases these may be combined with application of a treating agent to the textile material.

Of particular advantage for such applications is the excellent stability of the emulsions of the invention; these show no detectable separation of the organic and aqueous phases over a period of several days. In contrast, emulsions of similar composition but containing only the ethyl hydroxyethyl cellulose as stabiliser, that is to say omitting the anionic surface active agent or agents, show appreciable separation after as little as one day. Inferior results are also obtained by use of an anionic agent along (i.e., omitting the ethyl hydroxyethyl cellulose); it is possible to achieve a moderate degree of stability of the emulsions by increasing the concentration of the anionic agent, but this frequently has an adverse effect on the subsequent use of the emulsion where certain types of dyestuff are involved.

The invention is illustrated but not limited by the following examples in which all parts and percentages are by weight unless otherwise stated:

Example 1

0.70 Part of the dyestuff which is the disodium salt of 2-[2'-acetylamino-4'-(4"-chloro-6"-amino-1":3":5"- triazine-2"-ylamino)phenylazo naphthalene-4:8-disulphonic acid and 0.22 part of soda ash are dissolved in 13.3 parts of water, and 1.5 parts of Turkey Red Oil is then added and stirred until in solution. 1.5 Parts of ethyl hydroxyethyl cellulose of viscosity 20-35 cp (measured at 25.degree. C on a 5 % by weight solution in 80:20 toluene/ethanol) is dissolved in 132 parts of perchloroethylene and is stirred at high speed while the solution of dyestuff is slowly added over 5 minutes. High speed stirring is continued for a further 5 minutes, followed by slow stirring for 2 minutes to allow entrapped air to escape. The resulting emulsion has excellent stability.

A sample of cellulosic textile material is padded in the emulsion, dried and baked at 200.degree. C for 1 minute. The textile material is thereby evenly dyed a yellow colour.

If the above procedure is followed but omitting the Turkey Red Oil and increasing the amount of ethyl hydroxyethyl cellulose from 1.5 parts to 2.25 parts, the resulting emulsion is found to have considerably inferior stability, separation of aqueous phase being detectable after 18 - 20 hours, whereas the emulsion obtained using both ethylhydroxyethylcellulose and Turkey Red Oil shows no separation for at least 10 days.

If the procedure first described above is followed but omitting the ethyl hydroxyethyl cellulose and increasing the amount of Turkey Red Oil from 1.5 parts to 3 parts, a good emulsion is initially obtained but this shows separation of the aqueous phase after 3 days.

Example 2

The procedure of Example 1 is repeated, except that in place of the dyestuff there described there is used 1.1parts of the dyestuff which is the tri-sodium salt of copper phthalocyanine-3-(sulphonic acid).sub.3 -3 {N-[.beta.-6'-chloro-4'-methoxy-1':3':5'-triazin-2'-ylamino)ethyl]-sulphon amide}.

Cellulose textile material treated with the stable emulsion so obtained is evenly dyed a turquoise colour.

Example 3

The procedure of Example 1 is repeated, except that in place of the dyestuff there described there is used 0.75 part of the dyestuff which is the tetrasodium salt of 1-{2':5'-dimethyl-4'-[4"-(4'"-chloro-6'"-amino-1'":3'":5'"-triazin-2'"-yla mino)7"-sulphonaphth-1"-ylazo]phenylazo } naphthalene-2:5:7-tri-sulphonic acid.

Cellulosic material treated with the resulting stable emulsion is evenly dyed an orange-brown colour.

Example 4

The procedure described in Example 1 is repeated, except that the perchloroethylene is replaced by an equal weight of 1:1:1-trichloroethane. An emulsion of excellent stability is again obtained.

Example 5

The procedure described in Example 1 is repeated, except that the perchloroethylene is replaced by an equal weight of trichloroethylene. An emulsion of excellent stability is obtained.

Example 6

1.4 parts of the dyestuff described in Example 1 and 0.45 part of soda ash are dissolved in 26.6 parts of water. 1.5 parts of ethyl hydroxyethyl cellulose of viscosity 20-35cp, measured as described in Example 1, is dissolved in 132 parts of perchloroethylene and 1.0 part of tall oil is added, followed by 0.5 part of triethanolamine. The solution is stirred at high speed whilst the dyestuff solution is added dropwise as quickly as practicable. High speed stirring is continued for 5 minutes, followed by slow stirring for 2 minutes to allow de-aeration to take place. The resulting emulsion has excellent stability and may be employed for the continuous dyeing of cellulose textile materials according to the procedure described in Example 1.

Example 7

0.05 part of the dystuff which is the pentasodium salt of 1-(2'-methyl-3'-[4"-chloro-6"-sulphoanilino-1":3":5"-triazin-2"-ylamino]-5 '-sulphophenyl) -3-carboxy-4-[2"'-sulpho-4'"-(chlorosulphoanilino-1"":3"":5""-triazin-2""- ylamino)phenylazo]-5-pyrazolone and 1.1 parts of urea are dissolved in 1.9 parts of water; 0.145 part of a 45 % aqueous solution of the sodium salt of sulphated methyl oleate and 0.26 part of sodium dodecylbenzene sulphonate are then stirred in until dissolved. This solution is added to a solution of 0.025 part of ethyl hydroxyethyl cellulose of viscosity 20-35 cp, measured as described in Example 1, in 25 parts of perchloroethylene and mixed to give a coarse emulsion. This emulsion is gradually diluted with a further 164 parts of perchloroethylene to form a stable product.

Cellulosic textile material is batchwise dyed a yellow colour by immersion in a dyebath consisting of the above-described emulsion which is continuously agitated and gradually heated to boiling point, then maintained at the boil for 30 minutes.

Example 8

0.036 Part of the dyestuff identified in the Colour Index as C.I. Acid Yellow 72 is dissolved in 0.6 part of water, and 0.145 part of a 45 % aqueous solution of the sodium salt of sulphated methyl oleate is added. The dyestuff solution so obtained is added with good agitation to a solution of 0.025 part of ethyl hydroxyethyl cellulose of viscosity 20-35 cp. in 15 parts of perchloroethylene; the emulsion so formed is added with stirring to 149 parts of perchloroethylene at 30.degree. C, to yield a stable product.

The resulting emulsion is used for the batchwise dyeing of nylon textile materials to a yellow colour by immersing the textile material in the emulsion when maintained at 85.degree. C, at which temperature a clear solution is formed.

Example 9

The procedure of Example 8 is repeated, using in place of the dyestuff there described 0.016 part of the dyestuff which is identified in the Colour Index as C.I. Acid Red 266. A similar result is obtained.

Example 10

procedure of Example 8 is repeated, using in place of the dyestuff there described 0.015 part of the dyestuff 4-[4'-(phenylazo)phenylazo]-N-ethyl-N-(m-sulphobenzyl)aniline. A similar result is obtained.

Example 11

0.02 Part of the dyestuff identified in the Colour Index as C.I. Acid Blue 67 is dissolved in 0.6 part of water, and 0.045 part of dodecylbenzene sulphonic acid added. The solution so obtained is added with good agitation to a solution of 0.025 parts of ethyl hydroxyethyl cellulose of viscosity 20-35cp, in 15 parts of perchloroethylene; the emulsion so formed is added with stirring to a further 145 parts of perchloroethylene at 30.degree. C. The resultant dye liquor is employed for the batchwise dyeing of nylon textile material according to the following procedure :

Perchloroethylene is circulated through the nylon textile material at 40.degree. C for 10 minutes; the dye liquor in an amount sufficient to deposit from 1.25 to 1.5 % by weight of the dyestuff (based on the textile material taken), is then circulated through the material so treated at 40.degree. C for 15 minutes, after which the temperature is raised to 85.degree. C over a period of 40 minutes and then maintained at that value for 15 minutes. The material is dried at 70-80.degree. C.

Example 12

The procedure of Example 11 is repeated, using in place of the dyestuff there identified 0.016 part of the dyestuff referred to in Example 10. A similar result to that described in Example 11 is obtained.

Example 13

The procedure of Example 11 is repeated, using in place of the dyestuff there identifed 0.037 part of the dyestuff identified in the Colour Index as C.I. Acid Yellow 135. A similar result is obtained.

Example 14

The procedure of Example 11 is repeated, using in place of the dyestuff there identified 0.017 part of the dyestuff identified in the Colour Index as C.I. Acid Blue 40. A similar result is obtained.

Example 15

The procedure of Example 11 is repeated, using in place of the dyestuff there identified 0.036 part of the dyestuff identified in the Colour index as C.I. Acid Yellow 72. A similar result is obtained.

Example 16

1 part of Turkey Red Oil is dissolved in 30 parts of an 18 % solution in aqueous diethylene glycol of a fluorescent brightening agent which is an anionic stilbene derivative; this solution is added to a solution of 5 parts of ethyl hydroxyethyl cellulose, viscosity 20 - 35 cp., in 70 parts of per chloroethylene, whilst the latter is agitated with a "Silverson" homogeniser. Agitation is continued for 1 minute after the addition is complete. The resultant emulsion is viscous but pourable, and has excellent stability. It is suitable for the optical bleaching of cellulosic of polyamide fabrics and for this purpose it may be diluted with additional perchloroethylene without breakage of the emulsion occurring.

In a typical treatment, the diluted emulsion is padded on to a cellulosic fabric so as to deposit 0.05-0.5% by weight of the fluorescent brightening agent on the fabric; the solvent is then removed by passing the fabric through a steam chamber and the fabric is dried at 60.degree. C for 5 minutes.

The treated fabric is considerably brighter in appearance than the untreated fabric.

Example 17

1 part of Turkey Red Oil is dissolved in 30 parts of a 50 % aqueous solution of dimethyloldihydroxyethylene urea and is added to a solution of 1.5 parts of ethyl hydroxyethyl cellulose, viscosity 20-35 cp., in 70 parts of perchloroethylene whilst the latter is agitated with a "Silverson" homogeniser. Agitation is continued for 1 minute after the addition is complete. The resultant emulsion, which is viscous but pourable, has excellent stability. It is suitable for application together with a latent acid catalyst to cellulosic and polyester/cellulosic fabrics for the production of crease-resist and durable press finishes, and for this purpose it may be diluted with additional perchloroethylene without the emulsion breaking.

In a typical treatment, a latent acid catalyst such as monochloroacetic acid or stearamidomethylpyridinium chloride is added to the diluted perchloroethylene emulsion and the resulting composition is padded on to 100 % cellulosic or polyester-cellulosic blend fabric so as to deposit 4 - 8 % by weight of the dimethylol dihydroxyethylene urea on the fabric. The solvent is then removed by passing the fabric through a steam chamber, the fabric is thereafter dried at 60.degree. C for 5 minutes and then heated at a temperature of 155 - 160.degree. C for 3 minutes.

The treated fabric possesses much improved wet and dry crease recovery properties compared with the untreated fabric.

Example 18

0.4 part of sodium hydroxide is dissolved in 50 parts of a 15 % w/v. aqueous dispersion of a polyethylene terephthalate/polyoxyethylene terephthalate block copolymer; 2 parts of ethyl hydroxyethyl cellulose, viscosity 20 - 35 cp., are dissolved in 45 parts of perchloroethylene, followed by 2.6 parts of oleic acid. The aqueous dispersion is added over a period of 10 minutes to the oil phase, using a high-speed stirrer; after the addition is completed, stirring is continued at high speed for 3 minutes, followed by slow-speed stirring for 2 minutes. The resulting emulsion has excellent stability and is suitable for conferring durable antistatic and anti-soil effects on polyester, polyester/cellulosic and polyester/wool blend fabrics; it may be diluted for this purpose with additional perchloroethylene without the emulsion breaking.

The diluted emulsion is padded on to polyester fabric so as to deposit 1 - 3 % by weight of the polyethylene terephthalate/polyoxyethylene terephthalate block copolymer on to the fabric. The fabric is dried by heating at 70.degree. C for 20 minutes. The treated fabric is found to possess superior antisoil-redeposition, stain release and antisoil properties to the untreated fabric.

Example 19

0.2 Part of an azo dye, prepared by coupling 4-aminobenzene sulphonamide on to N-methyl-N-.beta.-cyanoethyl aniline, and 0.1 part of the polyurea deflocculating agent obtained as described below from mixed 2,4- and 2,6-tolylene diisocyanates and a fatty secondary amine derived from soya are gravel milled in 3 parts of perchloroethylene for 40 hours. The resulting dispersion is added with stirring to a solution of 1 part ethyl hydroxyethyl cellulose of viscosity 20-35 cp (measured at 25.degree. C on a 5 % by weight solution in 80:20 toluene/ethanol) dissolved in 115 parts perchloroethylene. A mixture of 5 parts of water and 1 part of Turkey Red Oil are slowly added with stirring to give an emulsion which is then further diluted with 690 parts of perchloroethylene.

Polyester textile material is batchwise dyed a yellow colour by immersion in a dyebath consisting of the above described emulsion which is continuously agitated and heated to 120.degree. C over 10 minutes, and maintained at 120.degree. C for 30 minutes.

The polyurea deflocculating agent used in the above Example is prepared by the following procedure. A solution in 32 parts of acetone of 73.7 parts of a commercially available 40 % solution in butyl acetate of polymerised mixed 2,4- and 2,6-tolylene diisocyanates containing 5.7 % of isocyanate groups and less than 0.5 % of free tolylene diisocyanate is gradually added to a stirred solution in 118 parts of acetone at 50-55.degree. C of 53.5 parts of a fatty secondary amine derived from soya, commercially available under the trade name Armeen 2S ("Armeen" is a Registered Trade Mark). The acetone is then removed by distillation up to a temperature of 100.degree. C under reduced pressure.

Example 20

0.5 Parts of the dye identified in the Colour Index as CI Basic Red 18 is dissolved in 5 parts boiling water and 5 parts Turkey Red Oil are added. The dye solution so obtained is added with good agitation to a solution of 1 part of ethyl hydroxy ethyl cellulose of 20-35 cp. in 115 parts perchloroethylene and the emulsion so formed is diluted with stirring with 687 parts perchloroethylene.

The resulting emulsion is used for the batchwise dyeing of polyacrylonitrile textile materials to a red colour by immersing the textile material in the emulsion for 30 minutes at 105.degree. C in a closed vessel with continuous agitation.

Claims

We claim:

1. A stabilized emulsion in a halogenated hydrocarbon solvent of an aqueous preparation of a textile treatment agent selected from dyestuffs and finishing agents, wherein there are present as emulsifying agents as ethyl hydroxyethyl cellulose having a solution viscosity, measured on a 5% solution by weight in 80:20 (by weight) toluene/ethanol of from 20 to 35 cp, and at least one anionic surface-active agent, the amount of water present in said emulsion being from 0.3 to 20% of the total weight of the emulsion.

2. A stabilised emulsion as claimed in claim 1, wherein the anionic surface-active agent is selected from salts of sulphonated castor oil, the triethanolamine salt of tall oil, the sodium salt of sulphated methyl oleate, sodium dodecylbenzenesulphonate and sodium oleate.

3. A stabilised emulsion as claimed in claim 1, wherein the halogenated hydrocarbon solvent is selected from perchloroethylene, trichloroethylene and 1:1:1-trichloroethane.

4. A process for the treatment of textile materials in which there is applied to the textile material a stabilised emulsion as claimed in claim 1 and the material is thereafter treated in known manner to fix the treatment agent thereupon.