CA1053857A

CA1053857A - Process for the dyeing of synthetic fibers

Info

Publication number: CA1053857A
Application number: CA221,029A
Authority: CA
Inventors: Hans-Ulrich Von Der Eltz; Hans-Joachim Wassmuth; Albert Reuther
Original assignee: Hoechst AG
Current assignee: Hoechst AG
Priority date: 1974-03-01
Filing date: 1975-02-28
Publication date: 1979-05-08
Also published as: DE2409727B2; FR2262714A1; BE826217A; SE7502212L; GB1503937A; DD119627A5; BR7501205A; AU7863475A; ATA149875A; FR2262714B1; DE2409727A1; ZA751145B; ES435030A1; SU576057A3; DK81575A; CS182277B2; AT344648B; CH587950B5; JPS50121581A; IT1033281B

Abstract

ABSTRACT OF THE DISCLOSURE

Process for the exhaust dyeing of wound bodies of synthetic fiber materials with water-insoluble developing black dyestuffs on the basis of the diazo and oxydation dyeing technique, wherein the wound-up textile material is heated to temperatures in the range of from 105° to 135° C in a pressure-tight dyeing vessel by replacing the air in said dyeing vessel by saturated or superheated steam, preparing the total dyebath in a separate batch vessel, which is likewise pressure-tight but connected with said dyeing vessel by pipes, also heating said dyebath to temperatures in the range of from 105° to 135°C. Control is maintained of the temperature within the mentioned limit values, the steam pressure in both closed systems and/or the application of external pressure securing the building up of a relative excess pressure of 5 to 10 atmospheres gauge in the batch vessel, and the hot dyeing liquor is pressed by the differential pressure within 3 to 60 seconds simultaneously from inside and from outside into the dry or wet wound bodies.

Description

This invention relates to a process for the dyeing of synthetic fibres.
Many variants of processes for the dyeing of synthetic fibres under high temperature ~HT) conditions according to exhaustion processes with developing blac~ dyestuffs on the basis of the diazo and oxydation technique are well known. The very long dyeing time ~4 1/2 hours) is criticized as a great disadvantage of all conventional methods.
According to the present invention, there is provided a process for the dyeing of textile materials made from synthetic fibres or from mixtures which contain such synthetic fibres, in the form of wound bodies, with water-insoluble developing black dyestuffs based on the diazo and oxidation dyeing technique according to the exhaust method at temperatures in the range of rom 105 to 135C, in which process the wound bodies contained ln a pressure-tight dyeing vessel are heated as well as de-aerated before the actual dyeing operation, and subsequently contacted with the dyeing liquor which has been separately heated to about dyeing temperature in a pressure-tight batch vessel, placed under a relative excess pressure of from ~.9 to 9.81 bars and then transferred in its total amount from said batch vessel into said dyeing vessel, after both vessels have attained a temperature of 105 to 135 C, whereupon the dyeing operation is continued by circulation of the dyeing liquor alternately from the inside to the outside and from the outside to the inside through the wound material, and developing of the dyestuffs is carried out under the above-mentioned pressure and temperature conditions according to the same principle, the improvement of which comprises: exposing the wound bodies to an atmosphere of steam at about dyeing temperature prior to contact with the dyeing liquor in order to preheat and de-aerate said textile materials; and transferring the dyeing liquor within a time of 3 to 60 ~econds by means of said relative excess pressure and towards the pressure of ~he air-free atmosphere of the steam into the dyeing vessel, simultaneously from both the inside and the outside of said wound bodies, thereby entirely condensing the steam in said vessel and filling it completely by the trans-ferred liquor.

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1~53857 The principle of the present invention consists in that a dyebath is prepared in a HT-vessel under the selected pressure and temperature conditions and is passed from there by means of pressure (pressurized steam, compressed air, pump pressure) into another autoclave filled with steam and containing the wound bodies of syn~hetic fibres, for example wound filaments or balls of piece goods on dyeing beams.
This is effected by pressing the bath simultaneously from the outside and from the inside into the wound bodies through correspondingly sized tubes, pumps and a distributor valve. This permits uniform distribution of the dyeing liquor in the goods to be dyed within an extremely short time, even with texturized synthetic filaments, without deformation of the wound bodies and filaments. In general, periods of less than 60 seconds, in most cases even less than 30 seconds, are requirèd. This rapid "shooting in" of the dyebath is achieved by a high pressure from the side of the vessel which contains the dyebath (pressure difference of 5 to 10 atmospheres gauge). The vessel in which the dyeing operation takes place is previously deareated by pressurized steam and at the same time the goods are pre-heated. The textile material may be dry or pre-washed, which process can be carried out in the dyeing vessel itself.
The dyeing vessel is pressure-tight, well isolated and provided with a heat exchanger of high capacity in order to hold the dyeing temperature constant. The bath itself is heated to about

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.f--~
:L0538~7 OE 74/F o63 135C in ths bath vessel and the~ pres~ed into the dyeing ~essel which is filled with steam. Within this proce~s the dyeing ~es~el may be filled completely al90 with c`losed val~e, provided that the corresponding differential pressure has built up, since the previously present steam condenses ~ith increasing pre!3su.re .
A modification of the proce~s of the invention consists in connecting the dyeing vessel filled with pressurized steam to a condensation apparatus which may be closed. This, too, enables the formation of a relative pressure difference which makes it possible to completely fill the dyeing vessel with the dyebath with closed de-aeration ~alve. It is also possi~le to produce a rel~tive under-pressure in the dy~ing vessel after the deaeration with steam, by a partial ~acuum from 2 vacuum line *hat can be closed. Hence there are several methods possible for producing the necessary pressure gradient. Complete evacuation of the dyeing vessel, however, is not necessary.
When the dyeing liquor is in the dyeing vessel, i.e.
when "shooting-in" is completed, the liquor i~ pumped with a circulation pump alternately from in~ide to the outside and from the outside to the inside through the ~round material, whereby the circulation pump may start during the filling phaseO
The selected dyeing temperature is maintained during this time.
Final fixatiGn of the dyestuff generally takes place within a short time. Under these temperature conditions it is of ad~antase to operate with a sufficiently high output of the pump. An output of more than 60 l/kg gi~es a good dyeing result.

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' ` ~ lV~38S7 HOE 74/F 063 The fact that the total dyeing liquor is introduced with high ~peed into the dyeing vessel and onto and into the more or less dry material in the form of ~ound bodies distinguishes it from the hitherto applied high temperature dyeing processe~
which with all their ~ariants ha~e largely been discussed in literature. Thus, according to the invèntion, not just a part of the dyeing liquor or a concentration dyastuff dispersion is introduced into *he dyeing ~esse.L, but the total dyeing liquor i8 pressed into it suddenly. It was not foreseeable that under 10 the-~e conditions level dyeings would be obtained, since dispersion diazo black dyestuffs have a high abso~ptive power at the~e temperature~v In additi~n it was not expected that the dyestuff dispersions would be suitabla for the penctration into wound bodies at such high temperature~, pressure differences and possible turb~lence~.
It i8 furthermore surprising that the dyestuff dispersions remain stable under these complicated apparati~e conditions and do not tend to agglomerations.
An essential advantage in the process of the invention resides in the fact that the absorptiv0 power of the dispersiol1 diazo black dyes*uffs i8 fully utilized at the high temperatures used.
As dyestuff~ there may be used the u~ual commercial - brands in the form of liquid preparations. Such dyestuffs are described in the Colo~r Index, 2nd edition (1971) ~nder the - - class desi$nation 'tAzoic Dyes".
For carrying out the process claimed synthetic fibres in any stage of processing which may be dyed according to the HT-. - ,: . . .

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.. . . . . ................. . .

~. .' - . . - . ' . .- . : : .

~ 57 HOE 74/F o63 dyeing method are ~uitable. However, the process is preferably used for texturized threads of polyester and threads and fibres of triacetate.
In the dyeing no other addition~ are nece sary except di~persing agents and the chemic,al products for adjusting the pH-value and to diazotize or purify the fibre material. The constancy of the pH-value 6 of the dyebath permit~ i reproducibility of the dyeings which is achieved by known suitable buffer ~ystems. The material to be treated may be dry - 10 or wet.
For a level dyeing it is important *hat the circulation of the bath is not interrupted when switching over, which,`
as i8 known, may be achieved by a four-way co~nection o~
valve control.

The followins Example~ illustrate the invention.
:

Example 1 Wound bodies of linear texturized polyester filAments were introduced into the dyeing vessel suitable for hi~h temperatùre dyeing; this ~essel was deaerated with saturated steam having 2 kp/cm and preheated with the goods. At the same time the total quantityyof bath required for the dyeing was prepared in a batch vessel; the quantity of bath amounted to 10 time~ the weight of ghe goods and contained, referred to the weight of the dry goods, a mixture dispersed in water of the componentY -:

.~ . . : .. : - . . .. .. : . . : , 1~5385 7 HOE 74/F o63 3.6 % of Disperse Black 1, C.I.No. 11365, 2.1 % of Azoic Coupling Comp. 20, C.I.No. 37530, 1 g/l of a condensation product of cresol and formaldehyde and 1 g/l of a slightly adjusted buffer on the basis of polymer phosphates and a 60% acetic acid (to pH 6).
An air pres~ure of 5.-5 kg/cm2 ~as then adjusted above the level of the bath.
The bath under pressur~e wa~ then heated to 135C. By opening a locXing valve in a suitable distributor line, the heated bath was allowed to enter into the wound bodies fro~
the in~ide as well as from the outside within 7 to 10 seconds.
After the beginning of the circulation of the bath a mixed temperature of about 125 C adjusted. With alternating circulation f the bath, the bath temperature was raised to 135 C and the good~ were dyed for 20 minutes at this temperature.
Then the dyeing apparatus was emptied by mean~ of high temperature (~T) discharge.
In the meantime an a~eous bath was prepared in the pressure ~ess~l with 2 cm3/l of sodium hydroxide solution`38 Bé (32.5 %), 0.5 g/l of the reaction product of 1 mol of nonyl phenol with mols of ethylene oxide and heated to 90C. The bath was introduced into the dyeing vessel fro~ the inside as well as from the outside by applying pres~ure with compressed air. A mixed temperature of .
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` 10$38S7 HOE 74/F o6 3 about 100 C adjusted. With alterna*ing circulation of the bath and a tempera*ure of 100C the goods were treated for 10 minutes. By continuous overflow rinsing the temperature was reduced to 60C and then the treating bath was allowed to flow off. Then the material was steamed for 5 minutes at a pressure of the saturated ~team of 1.5 kg/cm . In the meantim~
an aqueous bath was prepared in l;he press~re ~essel with 6 cm3 of acetic acid (60 ~) as wall as

4 g/l of sodium nitrite at 110 C and after superpo~ing compressed air, introduced into the dyeing ~essel under the Xnown conditions, A mixed temperature of 1~0 C was adjusted and the material W&S t~ated for 15 minutes at 110C with alternating circulation of the bath. After completing as usual a level and very fast black dyeing was obtained.

Example 2 Wound bodies of polyester filaments and cotton in a mixture ratio of 65:35 were introduced into a dyeing ~essel according to Example 1 and pre~iously steamed. The further treatment to dye the material was ef~ected, as de4cribed in Example 1, but with a mixture dispersed in water of the components (from the weight of the material) 2.35 % of Disperse Black 1, C.I.No. 11365 and 1.4 % of Azoic Coupling Comp. 20, C.I.No. 37530, - until the intermediate purification was finished. ~y continuous o~erflow rinsing the bath temperature was reduced to 30 C and the bath was subsequently allowed to discharge.

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~ - lOS38S~ HOE 74/F o63 The subsequent cro~-dyeing of the cotton portion wa3 effected with an aqueous bath containing (from the weight of the material) . o.6 ~ of ~he dye~tuff Sol.Vat Orange 1, C.I.No. 59106, 1 g/l of calcinated soda and 10 g/l of calcinated sodium sulfate during 20 minutes at a temperature of 30 C. Then the dyebath was discharged.
In the meantime a bath had been prepared in the pressure -10 vessel which contained on an aqueous base 6 cm3~1 of acetic acid (60 %) as well as 4 g/l of sodium nitrite and which, after superposing compressed air, wa~ heated to 135C. By opening a block~ng valve in a ~uitable distributor line the bath was introduced into the dyeing ves~el with the material from the inside as wèll as from the outside and after starting the pump for the circulation of the bath a mixed temperature of 85 C was adjusted. With an alternating circulation of th~ bath the temperature of treatment was increased to 110C and the material ~-as treated for 15 minutes.
After ~ompleting as usual an even dyeing was obtained, whereby the polye~ter fibre had a black color and the portion of cstton a yellow color.

~
Wound bodies of polyester filaments and cotton in a mixture ratio of 50:50 were introduced according to Example 1 , .
.

_ l~S3857 HOE 74/F 063 into a dyeing ve~sel and previously dyed. The further treatment for dyeing the goods wa3 effected, as de~cribed in Example 1, but with (from the weight Or the material) the dispersed mixture o~ dyestuff components in analogy to Example 2, until the high temperature ~taga wa~ finished when dyeing the polyester portion. The dyebath was subsequen~ly discharged under high temperature conditions (HT-.outlet).
In the meantime a bath ~as prepared in the pres~ure ~essel, - 10 which contained in the aqueou~ medium 7 % of the dyestuff Vat Black 9, C.I.No. 65230 and which was heated to 65C. After introducing compres-~ed air into the batch the bath was transferred from the inside and from the outside into the dyeing ~essel containing the textile 15 material and after starting the pump for the circulation of the bath a mixed temperature of 80C was adjusted. With an alternating circulation of the bath 40 cm3/l of sodium hydroxide so~ution 38Bé (32.S %) and 10 g~l of sodium dithionite (as a solution in water) 20 wsre addad after 20 minute~ over the open circulation and the . -material was dyed for ~0 minutes at 80 C. By cold continubu~ .
rinsing the pH-value of the textile material was ad3usted to pH 8 and then the rinsing bath was allowed to discharge. ~ :
The textile material was ~ubsequently steamed for 5 minutes 25 at 120C. .:
The diazotation bath prepared in the meantime and heated to 110C containing in water .
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- 1053857 HOE 74/F o63 8 cm3/1 of acetic acid (60 ~) ~ g/l of sodium nitrite, was snperposed in the pressure vessel with compressed air of

5.5 kp/cm and introduced in*o the dyeing ~essel from the inside and from the out~ide by opening a distributor line.
After starting the circulation of the bath a mixed temperature of 110C adjusted and the textile material was treated for 15 minutes with alternating bath circulation.
After completing as u~ual an even fast black dyeing was obtained on both fibre portions.

Example 4 Looped materials of triace*ate fibres were introduced in - a wound-up state into a HT beam dyeing appar~tus for piece goods. This vessel was $hen dearearated by saturated steam - of 0.~ kp/cm2 and pre-heated with the material. Simultaneously, the whole amount of the bath necessary for dyeing wa~ prepared in a batch vessel necessary for the dyeing; the quantit~ of bath amounted to 10 times the weight of the goods and contained, referred to the weight of the dry good~, a mixture disperYed in water of the components 3.0 ~ of Disperse Black 1, C.I.No. 11365, 1.75 % of Azoic Coupling Comp. 20, C.I.No. 37530, 1 g/l of the condensation product of cresol/formaldehyde and - 1 g~l of *he bRffer mentioned in Example 1, on the basis of polymer phosphates and 60 ~ acetic acid (to pH 6).
A pressure of compressed air of 5.5 kp/cm was adju~ted.
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... .. .. . .. _ _ _ _ _ . .. _ . __ _ _ -- ---- -- -- ' ' ' ' ' ' ' -- ' '-- ' . ' . ' ' 1;~-- ' "

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` 1053857 HOE 74~F o63 The bath preparation under pressure was heated to 110 C.
By opening a lockin~ valve in a suitable di~tributor line the heated bath wa~ allowed to enter within 7 to 10 seconds into the ~ound bodie-~ from the inside as well as from the outside. After beginning the bath circulation a mixed temperature of 110C wa~ adjusted. With alternating bath circulation the material was treated for 30 minute~. Then the dyeing liquor was cooled to 85 C. The matenal was then rinsed continuously at 60 C during 10 minutes.
For an intermediate purification 2 cm3/l of sodium hydroxide solution 38Bé (32.5 %) and 0.5 g/l of the reaction product of one mol of nonyl phenol and 10 mols of ethylene oxide were added to thi~ aqueous bath over the open circ~lation and the textile material was treated for 10 minutes at 70C.
It wa~ followed by a rinsing process at 60C. Then the material was diazotized during 15 minutes at 60 C with an aqueous bath containing 2.5 cm3/l of sulfuric acid (96 ~) and - 2 g/l of sodium nitrite.
The additives were introduced o~er the open circulation.
After completing as usual an even black dyeing was obtained.

Example 5 Wound bodies of linear texturized polyester filaments were introduced ac~ording to Example 1 into a dyeing Yessel and pre~iously -~teamed. The further treatment for dyeing the - ' '.~'"''.
. .
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- ~ 10538S~ OE 74/F o6 3 textile material was effected, as described in Exa~ple 1, but with a mixture dispersed-in wa*er of the component~:
3.0 % of Solvent 8rown, 3, C.I.No. 11360 1.75 ~ of Azoic Coupling Comp. 20, C.I.No. 37530 1 cm3/l of ~odium hydroxide ~olution 38Bé (32.5 %) 1 g~l of the condensation product of cresol/formaldehyde and g!l of qodium monochloracetate.
After impregnation the material was subjected to ip intermediate purification and diazotation a~ described in Example 1.
An even black dyeing was obtainedO
.
Example 6 Wound bodie~ of polyester fibres and cotton in a mixture ratio of 65:35 were introduced according to Example 1 into a dyeins ~e~el and previously steamed. The further treatment for dyeing the textile material was effected, as described in - Example 1, but with a mixture dispersed in water of the components (from the weisht of the material) 2.1 ~ of Disperse Black 1, G.I.No. 11365 and 1,2 ~ of Azoic Coupling Comp. 20, C.I.No. 37530, until the HT-s~age wa~ completed when dyeing the polyester ~ portion. The dyebath ~as discharged under high-temperature conditions (~IT-outlet).
- In the meantime a bath was prepared in the pres~ure ve~sel which contained on an aqueou~ base

6 % of a dyestuff Sol. Sulphur Black, C.I.No. 53186 and , ,,., ' ~ '~ --.: : . , ` : :. ~:

~ ' ' , :

11353~35i7 HOE 74/~ 063 5 g/l of calcinated ~odium carbonate.
After pressing compres~ed air onto the bath preparation ~nd heating to 115C, the bath was transferred from the inside and the outside into the dyeing ~ressel containing the textile material. After starting the circulation of the bath a mixed temperature of 110C was adjusteld. With alternating bath circulation 12 cm3/l of sodium hydrogen sulfide ~olution (21 ~) and 3 cm3/l of ammonium polysulfide solution (15 ~) were added after 10 minutes over the open circulation, then, in the same way 20 g/l of ~odium sulfate were added.
With alternating bath c2rculation the material was d~ed for 30 minutes at 95C. Then the material was rinsed continuously for 10 minutes. After dischargins the rinsing bath the dyestuff was oxyd~ed during 10 minutes at 40C with an aqueouq bath containing 1 cm3/1 of hydrogen peroxide (35 %), the oxydation bath was discharged, the dyeing was rin~ed fon a short time and the textile material was steamed for 5 minutes at 120C.
The diazotation bath prepared in the meantime in the pressure ~essel and heated to 110C, containing on an aqueous ba~e o cm3/l of acetic acid (60 %) and 4 g/l of sodium nitrite 2 - was superposed with compressed air of 5.5 kp/cm , and by opening a distributor line, introduced into the dyeing vessel -.. ,~ . . .. , . .. . .. ~ . . . . . . i .

1~ S 3~ HOE 74/F o63 from the inside as well as from the outside. After starting the bath circulation a mixed temperature of i10C appeared and the textile ma*erial was treated for 15 minutes with alternating bath circulation.
After completing as usual a even black dyeing was obtained on bot~ fibre portions '`~ ' ~ ` ' .

Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. In a process for the dyeing of textile materials made from synthetic fibres or from mixtures which contain such synthetic fibres, in the form of wound bodies, with water-insoluble developing black dyestuffs based on the diazo and oxidation dyeing technique according to the exhaust method at temperatures in the range of from 105° to 135° C, in which process the wound bodies contained in a pressure-tight dyeing vessel are heated as well as de-aerated before the actual dyeing operation, and subsequently contacted with the dyeing liquor which has been separately heated to about dyeing temperature in a pressure-tight batch vessel, placed under a relative excess pressure of from 4.9 to 9.81 bars and then transferred in its total amount from said batch vessel into said dyeing vessel, after both vessels have attained a temperature of 105° to 135° C, where-upon the dyeing operation is continued by circulation of the dyeing liquor alternately from the inside to the outside and from the outside to the inside through the wound material, and developing of the dyestuffs is carried out under the above-mentioned pressure and temperature conditions according to the same principle, the improvement of which comprises: exposing the wound bodies to an atmosphere of steam at about dyeing temperature prior to contact with the dyeing liquor in order to preheat and de-aerate said textile materials; and transferring the dyeing liquor within a time of 3 to 60 seconds by means of said relative excess pressure and towards the pressure of the air-free atmosphere of the steam into the dyeing vessel, simultaneously from both the inside and the outside of said wound bodies, thereby entirely condensing the steam in said vessel and filling it completely by the transferred liquor.

2. A process as claimed in claim 1, wherein the relative excess pressure for transferring the dyeing liquor from the batch vessel into the dyeing vessel is produced by compressed air.

(HOE 74/F 063)

3. A process as claimed in claim 1, wherein the wound bodies are exposed to an atmosphere of saturated steam, and in which for increasing the relative excess pressure the dyeing vessel is connected with a condensation line that may be closed.