WO1996018767A1

WO1996018767A1 - A process for dyeing polyester/cotton blends

Info

Publication number: WO1996018767A1
Application number: PCT/US1995/016025
Authority: WO
Inventors: Thomas Van Chambers; Christine Feuchtner
Original assignee: Hoechst Celanese Corporation
Priority date: 1994-12-13
Filing date: 1995-12-12
Publication date: 1996-06-20
Also published as: EP0839225A4; CA2207610A1; EP0839225A1; MX9704438A; JPH10510597A

Abstract

A single bath process for exhaust dyeing polyester and cotton fiber blends by the use of a fiber reactive, vinyl sulfone dye in admixture with a disperse dye under alkaline pH conditions.

Description

TITLE: A PROCESS FOR DYEING POLYESTER/COTTON BLENDS

BACKGROUND OF THE INVENTION

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation-in-part of US Patent Application Serial No.

08/355,711 filed December 13, 1995, now .

Technical Field

This invention is directed to the dyeing of cotton and polyester blends using

mixtures of disperse and fiber reactive dyes.

Background

In the prior, above-identified patent application we disclose the use of low

salt, vinyl sulfone fiber reactive dyes and disperse dyes in a one bath process for

dyeing polyester and cotton fiber blends. We have now discovered that the process

of our invention is also applicable to numerous other fiber reactive dyes capable of

providing high color yield under a low electrolyte dye bath concentration at a high

dye bath temperature and this application is directed to the broader aspects of our

invention.

Blends of cotton and polyester fibers are important textiles used in the

manufacture of clothing and other textile products. Unfortunately, the dyes and process conditions used to color cotton are different than the dyes and processes

used to dye polyester fibers.

Cotton fibers are dyed using fiber reactive dyes of the vinyl sulfone,

dichloroquinoxalone, halotriazine, and halopyrimidine types which are well known

in the art. The fiber reactive dyes are generally applied to the fiber under alkaline

conditions at a temperature from about 40° to 110°C from an aqueous solution

containing an electrolyte which promotes exhausting the dye from the dye bath to

the fiber. These dyes form a covalent chemical bond with the hydroxy groups of the

cotton and exhibit excellent fastness properties. The fiber reactive dyes are also

hydrophilic, have a high degree of affinity for cellulosic cotton fibers and are stable

under alkaline pH conditions but they are not as thermally stable as some other dyes.

Polyester fibers on the other hand are hydrophobic and are generally dyed

with disperse dyes which are also hydrophobic. The disperse dyes are sparingly

soluble in water and must be dispersed in water with the aid of a dispersing agent,

generally a surfactant in combination with other auxiliaries. Disperse dyes color the polyester fiber by diffusion into the fiber under the influence of heat and dyeing

auxiliaries. Unfortunately, disperse dyes are generally not stable at higher pH and

are normally applied at pH 5-7 at a temperature of 120° - 140°C. Additionally, the

disperse dye dispersion can be sensitive to electrolytes which tend to cause

dispersion instability. In commercial practice polyester/cotton blends are dyed by three well known

exhaust dyeing procedures which are: (1) a conventional two bath procedure; (2) a

reverse two bath procedure and (3) a one bath, multi step procedure.

In the conventional two bath procedure the polyester/cotton blend is first

dyed with a disperse dye in a dye bath at pH 5-7 at 120° - 140°C to dye the polyester

fiber component of the blend. The polyester/cotton blend is then removed from this

first dye bath and transferred to a second dye bath containing a fiber reactive dye,

electrolyte and alkali. Alternatively the disperse dye bath is removed from the dye

vessel and replaced with the fiber reactive dye bath. The cotton component of the

blend is then dyed under alkaline conditions at a temperature from about 60° -

110°C. The reverse two bath procedure comprises a reversal in the order of dyeing

versus the conventional process; first dyeing the cotton with the fiber reactive dye

and then the polyester with the disperse dye in separate dye baths. In the one bath

multi-step procedure, a single dye bath is prepared and the cotton portion of the blend is dyed under alkaline conditions and low temperature in the presence of

electrolyte. The dye bath is then acidified to lower the pH and a disperse dye is

added and the polyester portion of the blend is dyed at 120°C to 130°C.

US Patent No. 4,359,322 (Neal) discloses a one process for dyeing polyester

cotton blends with alkaline-stable disperse dyes and fiber reactive dyes of the vinyl to 40°C to 1 10°C to effect dyeing of the cotton portion of the blend with the fiber

reactive dye component. The dye bath is held at the selected temperature for an

appropriate time to exhaust the fiber reactive dye into the cotton fiber; generally

from abut 15 minutes to about one hour. Excellent results have been obtained at

80°C for 30 minutes. The dye bath is then heated to about 120°C to 140°C to dye

the polyester portion of the blend with the alkali-stable disperse dye. Excellent

results have been obtained at 130°C for 30 minutes. The dye bath is then cooled and

the fabric rinsed and dried. Normal dye bath auxiliaries may be employed in the

process; e.g. scouring agents, leveling aids, water softeners etc.

The amount of electrolyte and alkali used in the dye bath is dependent upon

the amount of low salt, fiber reactive, dye used in the dye bath. Deep shades require

more dye which in turn requires more electrolyte and more alkali.

The appropriate amount of alkali and electrolyte may be determined by

simple experimentation. The electrolyte concentration will typically range from

about 25 grams per liter at one percent of a fiber reactive dye to about 50 grams per

liter at a six percent fiber reactive dye level (percentages by weight on fabric) at a

liquor ratio of 10: 1. Similarly, the amount of alkali required will be dependent on

the fiber reactive, vinyl sulfone concentration. Typically the amount of alkali

required will be in the range from about 0.5 to about 3 percent over a dye concentration from about one weight percent to six weight percent. The low salt. that temperature for a time of about 15 minutes to several hours, preferably about 30

minutes at 100°C most preferably at about 75°C to about 85°C. The dye bath is then

heated to a temperature of about 120° - 140°C for about 15 minutes to about 1.0

hour preferably about 30 minutes and the dye bath is cooled, the fabric rinsed and

dried. The low salt fiber reactive dyes useful in the invention provide high

performance and uniform dyeings. The process of the invention achieves these

superior dyeings at lower costs for energy, raw materials and high productivity while

simultaneously providing the environmental advantage of a low salt effluent.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

This invention is directed to a method of dyeing polyester/cotton blends and

dye compositions useful therein. Polyester/cotton blends may be dyed according to

the invention by a single bath exhaust dyeing procedure using alkali-stable disperse

dyes and low salt, fiber reactive dyes in an aqueous dye bath solution under alkaline

pH conditions.

The process of the invention comprises dyeing polyester/cotton blends by the exhaust dyeing method. In the process of the invention an aqueous dye bath is

prepared containing an alkali-stable disperse dye component, a low salt, fiber

reactive dye component, an electrolyte and an alkali component. According to the

process of the invention, the dye bath containing the polyester/cotton blend is heated to 40°C to 1 10°C to effect dyeing of the cotton portion of the blend with the fiber

reactive dye component. The dye bath is held at the selected temperature for an

from abut 15 minutes to about one hour. Excellent results have been obtained at

the fabric rinsed and dried. Normal dye bath auxiliaries may be employed in the

process; e.g. scouring agents, leveling aids, water softeners etc.

The amount of electrolyte and alkali used in the dye bath is dependent upon

the amount of low salt, fiber reactive, dye used in the dye bath. Deep shades require more dye which in turn requires more electrolyte and more alkali.

The appropriate amount of alkali and electrolyte may be determined by

simple experimentation. The electrolyte concentration will typically range from about 25 grams per liter at one percent of a fiber reactive dye to about 50 grams per

the fiber reactive, vinyl sulfone concentration. Typically the amount of alkali

required will be in the range from about 0.5 to about 3 percent over a dye

concentration from about one weight percent to six weight percent. The low salt. fiber reactive, dyes can be used in their free acid form or the alkali salt form,

preferably in the salt form.

The process of the invention provides high quality dyeings with the

following advantages: high productivity through reduced cycle time, lower energy

usage, high dye bath exhaust (improved color yield and build up) and low

environment emissions. The process of the invention provides a color yield of

approximately 90% of the strength achieved under normal dyeing conditions. In

addition, in the conventional dyeing procedures for polyester/cotton blends, a fiber

reactive dye usually loses 20 to 50% of its strength. This loss in color yield is

avoided with the process and compositions of this invention.

The fiber reactive dyes useful in the invention have the following

characteristics: (a) they may be used at a low electrolyte concentration in the dye

bath; e.g. in an amount of 50 grams/liter or less, preferably 40 grams/liter or less

while providing high color yield i.e. at least 80% of the color yield obtained when

dyed at 1 10 to 140 grams per liter dye bath electrolyte concentration, preferably at

lesat 85% and most preferably 90% or more; (b) they provide high fixation and high

color yield at a dye bath pH of from about 8 to 1 1 preferably about 8.5 to 10.5 and

(c) they are thermally stable at dye bath temperatures in the 110° to 140°C range.

The following test procedure is used to determine whether a particular water soluble,

fiber reactive dye is a low salt dye for the purpose of this invention. After where Z is a group capable of being eliminated by the action of an alkaline reagent.

Z may be sulfato, phosphato, chlorine, bromine, thiosulfato, etc. In the alternative,

the dye may contain one or more monofluorotriazine or monochlorotriazine reactive

groups and one vinyl sulfone group. Generally it has been found that dyes of the vinyl sulfone, monochlorotriazine and monofluorotriazine having a single reactive

substituent are not acceptable for use in this invention. However, an exception to

this finding is a dye having one reactive group and a cyanamide substituent on an s-

triazine group.

Exemplary vinyl sulfone dyes and mixed vinyl sulfone, monochlorotriazine,

monofluorotriazine dyes useful in the invention follow. In the dye list which follows the following abbreviations are used for the reactive groups:

VS - vinyl sulfone MCT - monochlorotriazine MFT - monofluorotriazine

Reactive Yellow 1 Dye

2 VS groups

10 process conditions (140-160°F) when dyed in accordance with the process of the

invention; more preferably about 85% and most preferably about 90% or more.

These dyes are defined as low salt, fiber reactive dyes for the purpose of this

description.

The following screening tests illustrate the performance criteria.

Remazol® EF Yellow 2R was dyed at 140°F according to the above

procedure (145°F for 45 minutes) and gave a color yield of 1.9 CDU's when the

same dye was dyed at 175°F - 265°F according to the above procedure the color

yield was 0.775 CDU's. This dye was unacceptable since the high temperature color

yield is only 55% of the low temperature value (0.775/1.9 x 100 = 55%).

Cibacron Yellow LS R was dyed according to the above procedure (160°F

for 45 minutes), and the color yield at 160°F was 2.1 CDU's and at 175°F - 265°F

the dye yield was 2.037. This dye was acceptable as the high temperature color

yield was 97% of the low temperature color yield.

Typically, these low salt, fiber reactive, dyes that are useful in the invention

may be further characterized as follows: The fiber reactive component may be of the

vinyl sulfone series which are well known in the art. The vinyl sulfone dyes useful

in the invention should contain at least two fiber reactive groups of the general

formula — SO₂Y, where Y represents the vinyl group or the group — CH₂CH₂Z where Z is a group capable of being eliminated by the action of an alkaline reagent.

Z may be sulfato, phosphato, chlorine, bromine, thiosulfato, etc. In the alternative, the dye may contain one or more monofluorotriazine or monochlorotriazine reactive

groups and one vinyl sulfone group. Generally it has been found that dyes of the

vinyl sulfone, monochlorotriazine and monofluorotriazine having a single reactive

triazine group.

Exemplary vinyl sulfone dyes and mixed vinyl sulfone, monochlorotriazine,

monofluorotriazine dyes useful in the invention follow. In the dye list which

follows the following abbreviations are used for the reactive groups:

VS - vinyl sulfone MCT - monochlorotriazine MFT - monofluorotriazine

Reactive Yellow 1 Dye

2 VS groups Reactive Scarlet 1 Dve

1 VS group & 1 MFT group

Reactive Red 1 Dye

2 VS groups & 1 MCT group

Reactive Red 2 Dye

2 VS groups & 1 MCT group

Reactive Red 3 Dve

3 VS groups & 1 MCT group

Reactive Orange 1 Dye

1 VS group & 1 MCT

Reactive Red Violet 1 Dye

2 VS groups & 1 MCT group Reactive Red Violet 2 Dve

2 VS groups & 1 MCT group

Reactive Red Violet 3 Dve

2 VS groups & 1 MCT group

Reactive Violet 1 Dve

2 VS groups and 1 MCT group Reactive Red Violet 4 Dye

2 VS groups & 1 MCT group

Reactive Red Violet 5 Dve

2 VS groups & 1 MCT group

Reactive Red Violet 6 Dye

2 VS groups & 1 MCT group Reactive Blue 1 Dye

2 VS groups & 1 MCT

Reactive Blue 2 Dye

1 VS group & 1 cyanamide group

Reactive Blue 3 Dye

2 VS groups & 1 MCT group Reactive Blue 4 Dve

VS group & 1 MCT group

Reactive Blue 5 Dve

2 VS groups

Reactive Blue 6 Dye

2 VS groups Exemplary commercial dyes of the vinyl sulfone type and mixed vinyl

sulfone, monochlorotriazine or monofluorotriazine reactive group type useful in this

invention are: Remazol® Red M-RB, Remazol® EF Red BS, Remazol® EF Blue

FB, Remazol® Brilliant Yellow 3 GL, Remazol EF Red 2 BT dyes which are

available from DyStar L.P., Charlotte, NC, USA; Cibacron® Orange C-G,

Cibacron® Yellow C-R dyes available from Ciba-Geigy Corporation, Summit, NJ,

USA.

Low salt fiber-reactive dyes containing two or more reactive

monohalotriazine (monochloro or monofluorotriazine) group may also be used in the invention. The monochlorotriazine and monofluorotriazine groups have the

formula:

An exemplary low salt dye useful in the invention having at least two

monohalotriazine groups is a dye of the formula:

X = Cl or F

Exemplary commercial dyes of the bis-monochlorotriazine and bis-

monofluorotriazine reactive group type useful in the process of the invention are :

Procion® Red HE-313, (Reactive Red 120), Procion® Orange HE-R, (Reactive Orange 84), Procion® Blue HE-GN, (Reactive Blue 187:1) dyes available from ICI

Ld, UK; and Cibacron® Blue LS 3R, Cibacron® Scarlet LS. and Cibacron Yellow

LS R dyes available from Ciba-Geigy Corporation, Summit, N. J.

Low salt fiber reactive dyes having one or more fiber reactive

dichloroquinoxalones groups may be used in the invention. The

dichloroquinoxalone group has the formula:

An exemplary low salt, fiber reactive dye having one dichloroquinoxalone

fiber reactive group that may be used in the process of this invention is:

An exemplary commercial dye of the dichloroquinoxalone reactive group

type is Levafix® Golden Yellow EG available from DyStar LP. Charlotte, NC.

A low salt, fiber reactive dye containing one or more reactive groups of the

trihalopyrimidine series may also be used in the process of the invention. The

trihalopyrimidine reactive group has the formula:

wherein X is independently selected from Cl and F; preferably at least one X

substituent is selected from F.

Exemplary low salt, fiber reactive dyes having one trihalopyrimidine group

that may be used in the process of this invention are:

and

Exemplary dyes of the trihalopyrimidine reactive group type are Levafix® E-3GA, (Reactive Orange 64). Levafix® Scarlet E-2GA, (Reactive Red 123), and

Levafix® Red E-6BA, (Reactive Red 159), available from DyStar LP. Charlotte,

NC.

The foregoing description is intended to be illustrative and not limiting. Low

salt fiber reactive dyes within the scope of this invention include dyes wherein the

fiber reactive groups may be of different types; e.g. a dichloroquinoxalone group and one or more fiber reactive groups selected from vinyl sulfone, monochlorotriazine.

monofluorotriazine and trihalopyrimidine or multiple fiber reactive groups selected from the same class e.g. two trichloropyrimidine groups or two

dichloroquinoxalones etc. An exemplary dye having different fiber reactive groups

which provides excellent results is Levafix® Navy E-BNA dye (available from

DyStar L.P., Charlotte, N.C.) with one vinyl sulfone fiber reactive group and one

difluoromonochloropyrimidine group.

The alkali-stable disperse dyes useful in this invention are characterized by

being chemically stable in the pH range from about 8 to about 11. An alkali-stable

disperse dye also be further characterized in that it does not undergo random tone

shifts at high temperature and alkaline conditions and that the disperse dye

dispersion provides level dyeings. These dyes are known; see for example US

Patent No. 4,359,322, col. 11-12. Exemplary alkali-stable disperse dyes useful in

this invention have the following formulae:

Disperse Yellow 1 Dye

Disperse Yellow 2 Dye

Disperse Red 1 Dye

Disperse Violet 1 Dve

Disperse Violet 2 Dye

11 Disperse Orange 1 Dye

Disperse Blue 1 Dve

Disperse Blue 2 Dve

Exemplary alkali-stable disperse dye are commercially available from

DyStar L.P., Charlotte, NC; e. g. the following disperse dyes:

Dianix® Yellow 5G-E Dye Dianix® Blue FBL-E Dye

Dianix® Yellow AC-E Dye Dianix® Blue BG-FS 200 Dye (Disperse Blue 73) Dianix® Yellow H2G-FS Dye Dianix® Dark Blue B-SE 200 Dye (Disperse Yellow 160)

Dianix® Blue GR-E 140 Dye Dianix® Yellow UN-SE 200 New Dye (Disperse Blue 81) Dianix® Blue GRN-E 200 Dye

Dianix® Orange UN-SE New Dye Dianix® Turquoise Blue G-FS 200 Dye Dianix Orange GS-E Dye (Disperse Orange 73)

Dianix® Navy BG-SE 200 Dye

Dianix® Red F-BE 220 Dye (Disperse Red 60) Dianix® Grey R-SE Dye

Dianix® Red AC-E Dye Dianix® Black RB-FS 200 Dye

Dianix® Red HBL-A Dye Resolin® Yellow 5GL 200 Dye

Dianix® Red UN-SE Dye Resolin® Red F3BS 150 Dye

Dianix® Rubine KB-FS Dye Resolin® Red Violet FBL 200 Dye Dianix® Violet FHRL-SE Dye Resolin® Blue F2GS Dye

The process of the invention is conducted within a pH ranging from about 8 to about 1 1 ; preferably in the range of from about 8.5 to 10.5. The pH of the dye

bath is controlled by the use of an alkali, preferably in conjunction with a buffering

agent. Exemplary alkali are sodium, potassium and lithium hydroxides and

carbonates, preferably potassium hydroxide. Exemplary buffers include sodium

bicarbonate, disodium hydrogen phosphate, borax, potassium hydrogen phosphate

and sodium metasilicate. A mixture of potassium hydroxide and sodium

metasilicate is a preferred combination for controlling the pH of the dye bath.

Optionally, the pH may be controlled by a metered addition of alkali solution to the

dve bath. The following examples illustrate the invention. These examples are to be

considered illustrative and are not intended to limit the scope of the invention or the

claims. Percentages unless indicated otherwise are weight percent based upon the

weight of fabric.

Example 1

A dye bath was prepared at approximately 32°C (90°F) following ingredients

at a liquor ratio of 10: 1.

2.0% Reactive Red Violet 5 Dye

0.8% Disperse Violet 1 Dye 40.0 g/1 Glauber's Salt (sodium sulfate)

1.5% Remol^® FB alkali (mixture of KOH & Na₂SiO₃)

2.0% Remol^® DC surfactant (an anionic phosphate ester of a fatty alcohol)

A test specimen of a 50:50 polyester/cotton fabric in the amount of 10 grams

was added to the bath. The temperature of the dye bath was raised from 32°C to

approximately 80°C (175°F) at the rate of about 1°C per minute (2°F/min) and held

at 80°C for 45 minutes. The dye bath temperature was then raised to approximately

130°C at the rate of l°C/minute and held at 130°C for 30 minutes. The bath was

then cooled to 90°C and the fabric was rinsed and dried. The color yield in Color

Density Units (CDU's) was measured on the fabric using a computer assisted

spectrophotometer. The color yield on the fabric was 1.801 CDU^'s. The Remol

FB alkali and Remol^® DC surfactant used in this example are products available

from Hoechst Celanese Corporation, Somerville. New Jersey. 08876, USA. Comparative Example 1 Example 1 was repeated using as the fiber reactive, vinyl sulfone dye CI Reactive Violet 5. The color yield was measured on the dyed fabric and it was 0.672

CDU's. In comparison to the dyeing of Example 1, the color yield on this dyeing

was 37% (0.672/1.801) of that of Example 1.

Example 2

The procedure of Example 1 was repeated except the dye bath contained the

following ingredients.

2.0% Reactive Red- 1 Dye

0.8% Disperse Red-1 Dye

40.0 g/1 Glauber's Salt

1.5% Remol^® FB alkali

2.0% Remol^® DC

The color yield on the dyed specimen was 2.381.

Comparative Example 2

Example 2 was repeated except the fiber reactive, vinyl sulfone used was CI

Reactive Red 180. The color yield on the dyed fabric was 0.88 CDU. In comparison to the dyeing of Example 2 the color yield on this dyeing was 37%

(0.88/2.381 ) of that of Example 2.

Example 3

A dyebath was prepared at 100°F consisting of the following:

1.50 % Levafix® Scarlet E-2GA 2.50 % Remazol® EF Red BS 1.00 % Levafix® Blue E-GRN 0.30 % Dianix® Orange G-SE 0.35 % Resolin® Red F3BS 50.0 g/1 Glauber's Salt 2.00 % Solegal P ( auxiliary ) 2.50% Remol FB ( alkali )

A 20/80 polyester / cotton fabric was dyeing from the above prepared

dyebath at a liquor ratio of 10:1 ( dye bath : weight of fabric ) as follows:

The temperature of the dyebath was raised at a rate of 2°F / minute to a

temperature of 175°F (80°C) and run for 15 minutes. The temperature was then

raised at a rate of 3°F / minute to a temperature of 265°F and run for 20 minutes. The

dyebath was cooled and dropped. The fabric was rinsed, soaped, rinsed, and dried.

The result was a maroon colored dyeing with good levelness, fabric coverage, color

yield, and fastness properties.

Having described the present invention in detail, it is obvious that one skilled

in the art will be able to make variations and modifications thereto without departing

from the scope of the invention.

Claims

WE CLAIM:

ClaimJL

A process for dyeing blends of polyester and cotton fibers which comprises

exhaust dyeing said blend in a dye bath which comprises a water-soluble, fiber-

reactive dye component and an alkali-stable disperse dye component in admixture in

the presence of an electrolyte and an alkali wherein the pH of said dye bath is from

about 8 to 1 1; wherein the concentration of said electrolyte is less than about 50

grams per liter, and wherein said fiber reactive dye component comprises at least

one low salt, fiber-reactive dye.

Claim 2

A process according to Claim 1 wherein said low salt, fiber reactive dye

comprises at least two fiber reactive groups independently selected from vinyl sulfone, monochlorotriazine and monofluorotriazine fiber reactive groups.

Claim 3

A process according to Claim 1 wherein said low salt, fiber reactive dye comprises at least one fiber reactive group selected from the dichloroquinoxalone

and trihalopyrimidine fiber reactive groups; wherein the trihalopyrimidine halo

substituents are independently selected from chloro and fluoro. Claim 4

A process according to Claim 3 wherein said trihalopyrimidine comprises at

least one fluoro substituent.

Claim 5

A process according to Claim 1 wherein said low salt, fiber reactive dye has

at least one fiber reactive group selected from the vinyl sulfone monochlorotriazine

and monofluorotriazine fiber reactive groups and at least one cyanamide substituted

s-triazine group.

Claim 6

A process according to Claim 1 wherein said low salt, fiber reactive dye has

at least one fiber reactive group selected from the vinyl sulfone fiber reactive group

and at least one cyanamide substituted s-triazine group.

Claim 7

A process according to Claim 1 wherein a mixture of potassium hydroxide

and sodium metasilicate is used to control the dye bath pH.

Claim 8

A process according to Claim 2 wherein a mixture of potassium hydroxide

and sodium metasilicate is used to control the dye bath pH. Claim 9

A process according to Claim 3 wherein a mixture of potassium hydroxide and sodium metasilicate is used to control the dye bath pH.

Claim 10

A process according to Claim 4 wherein a mixture of potassium hydroxide

and sodium metasilicate is used to control the dye bath pH.

Claim 1 1

A process according to Claim 5 wherein a mixture of potassium hydroxide

and sodium metasilicate is used to control the dye bath pH.

Claim 12 A process according to Claim 6 wherein a mixture of potassium hydroxide

and sodium metasilicate is used to control the dye bath pH.

Claim 13

A process according to Claim 2 wherein said fiber reactive dye component

comprises at least one low salt fiber reactive dye selected from: Reactive Yellow 1 Dye

Reactive Scarlet 1 Dye

Reactive Red 1 Dye

Reactive Red 2 Dve

Reactive Red 3 Dye

Reactive Orange 1 Dve

S0₂C₂H₄θS0₃H ,

Reactive Red Violet 1 Dye

Reactive Red Violet 2 Dye

Reactive Red Violet 3 Dye

Reactive Violet 1 Dye

Reactive Red Violet 4 Dve

Reactive Red Violet 5 Dve

Reactive Red Violet 6 Dve

Reactive Blue 1 Dve

Reactive Blue 2 Dye

Reactive Blue 3 Dve

Reactive Blue 4 Dve

Reactive Blue 5 Dye

and Reactive Blue 6 Dve

Claim 14 A process according to Claim 13 wherein said pH is controlled by a mixture

of potassium hydroxide and sodium metasilicate.