CA2158884A1 - Production of aminated regenerated cellulose - Google Patents

Abstract

Process for producing aminated regenerated cellulose fibers, which comprises preparing a solution of cellulose and a protein having a molecular weight of greater than 50,000 or a natural product comprising such a protein and spinning fibers from this solution.

Description

21~8~8 1 HOECHST AKTIENGESELLSCHAFT HOE 94/F 288 Dr.HU/do Description Production of aminated regenerated cellulose Viscose fibers have essentially the same dyeing charac-teristics as cotton fibers. At present, the dyeing of natural or regenerated cellulosic fibers requires alkali-donating agents and also electrolytes in order that satisfactory fixation results may be obtained with reactive dyes. It is precisely these necessary additions, however, which are unacceptable for ecologically improved dyeing processes. The future will therefore increasingly belong to regenerated fibers, ba~ed on cellulose, which have been converted beforehand without additional process steps into modifications which have a high affinity for dyes, i.e. which are dyeable without salt and alkali.
Fibers thus modified resemble animal fibers, such as wool or silk, in their chemical behavior and can be dyed with anionic dyes under neutral conditions without further salt or alkali additions.

Modifications of viscose have already been described in the literature. US-A-3 793 419, for instance, describes a process for producing viscose fibers having modified dyeing characteristics. However, the process is extremely complicated and uneconomical. In addition, polyamine-amides are used which significantly alter the nativecharacter of the fiber. This iB evident, for example, from the use of disperse dyes in the later dyeing.

US-A-3 305 377 too iB concerned with "aminalized fibers".
The additions are aminoethyl- and diethylaminoethyl-celluloses in high concentration, and the dyeing is doneexclusively with acid dyes.

It is an object of the present invention to provide modified viscose fibers in order that textiles composed 21~888 l of such fibers may be dyed with anionic dyes with low amounts of salt and alkali and a material with a soft hand may be obtained.

It has been found that the use of proteins as addition to the viscose dope or to the cellulose prior to the alkalizing makes it possible to produce a viscose fiber which surprisingly has significantly more affinity for anionic dyes and differs greatly from conventional viscose fibers in the other properties desired, for example by a soft hand.

The present invention accordingly provides a process for producing aminated regenerated cellulose fibers, which comprises preparing a solution of cellulose and a protein having a molecular weight of greater than 50,000 or a natural product compriæing such a protein and spinning fibers from this solution.

In a preferred embodiment, a) cellulose and a protein having a molecular weight of greater than 50,000 or a natural product comprising such a protein are mixed and the mixture is alkalized and the resulting alkalized mixture iæ reacted with carbon disulfide or b) a protein having a molecular weight of greater than 50,000 or a natural product comprising such a protein is dissolved in sodium hydroxide solution and added to a fiber grade viscose, and the viscose dope obtained from a) or b) is forwarded into an acid spinbath and spun into fibers.

The reaction with carbon disulfide advantageously takes place at temperatures from 15 to 30C. Subsequent spin-ning into an acid spinbath affords the aminated cellulose fibers of the invention.

It is also possible to produce the fibers of the invention by other customary processes, familiar to the person skilled in the art, for producing cellulosic fibers from solution, for example the cupro process, the 215~81 Lyocell process or the process involving low-substituted cellulose ethers. These processes involve dissolving the cellulose and the protein in a suitable organic solvent, for example N-methylmorpholine N-oxide/ water, reacting them with each other and spinning fibers directly from the solution.

Sp;nn;ng into an acid spinbath affords fibers which can be dyed according to the invention using low-electrolyte or completely electrolyte-free and low-alkali or alkali-free dyeing liquors (including print pastes and inkjetfluids). For the purposes of the present invention, low-electrolyte dyeing liquors are those having an electro-lyte content below 15 g/l and low-alkali dyeing liquors are those having a pH of not more than 8.5.

The proteins and protein-containing natural products used for the process of the invention occur in nature for example as keratins, collagen-containing natural products and albumins. Examples of preferred keratins are body hairs, hooves, horns, claws and nails of m G als, bird feathers, spinning threads of insects, tortoiseshell and fish scales. Examples of preferred collagen-containing natural products are hide, leather, cartilage, connective tissue, tendons, sinews of mammals, in particular gelatin, glutin and boneglue. Suitable albumin is in particular egg albumin or else eggs as such.

The protein-containing natural products used for the process of the invention may also include other, concomitant component~, in which case it is also possible to use for example meat, meat meal, fish, fish meal or processing products thereof.

The proteins are denatured in the course of the dissolv-ing step. In addition to the animal proteins mentioned, however, it is also possible to use synthetic proteins having a molecular weight of greater than 50,000.

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The textile modified fiber material which i8 used in the dyeing process of the invention can be present in all stages of processing, for instance as yarn, staple, slubbing and piece goods (fabrics).

The amination of the regenerated cellulose according to the invention probably does not involve a chemical reaction between the cellulose and the alkalized or dissolved protein; instead the two components adhere to each other in the fiber 80 strongly as a consequence of Van-der-Waals interactions that the protein cannot be washed out.

The aminated textile fiber materials are dyed according to the invention analogously to known processes for dyeing and printing fiber materials with water-soluble textile dyes and through the use of the temperature ranges and customary dyestuff quantities known for this purpose, except that the dyebaths, padding liquors, print pastes or inkjet formulations require no quantitative addition of alkaline compounds, as customary for fixing fiber-reactive dyes, nor customary additions of electro-lyte salts. The dyeing of the modified viscose according to the invention takes place between pH 4 and pH 8.5, depending on the nature of the dye. If commercial textile dyes are used, salt contents of 0.01 to 0.5% by weight, based on the dyeing liquor, are normally present. Without the amination of the cellulose fibers according to the invention, however, this salt content would be too low for a successful dyeing process by a factor of 50 to 1000 .

The alkalized or dissolved protein is advantageously incorporated into the viscose spinning dope without emulsifiers. The protein is added in an amount of 1 to 20% by weight, preferably 1 to 12% by weight, based on the cellulose content of the sp; nn; ng dope, prior to the precipitation and forming.

_ 5 21~88~
The forming of the viscose i8 carried out by conventional methods, for example by means of spinnerets openings, a subsequent coagulation bath and optionally further aftertreatment baths.

The fibers obtained by the methods described can be processed into woven and knitted fabrics and then dyed by a very wide range of processes, such as exhaust, padding and modern printing processes, which also include inkjet processes, without the use of salt or alkali.

The present invention also provides a process for dyeing and printing cellulosic textiles with anionic dyes, which comprises performing the dyeing with a dye solution which is free of additional electrolyte salts, at a pH between 4 and 6 in the case of direct and acid dyes and at a pH
between 6 and 8.5 in the case of reactive dyes, while uæing a regenerated cellulose fiber material aminated according to the invention.

Suitable dyeing processes include for example various exhaust processes, such as dyeing on the jigger or on the reel beck or dyeing from long or short liquor, dyeing in jet dyeing machines, dyeing by cold pad-batch processes or by a pad-superheated steam fixation process. Suitable printing processes include conventional printing tech-niques, including inkjet printing and transfer printing.

The dyes which are used for dyeing the modified cellulose are generally anionic in nature. In addition to the so-called acid or direct dyes, it is the fiber-reactive textile dyes which are capable of reacting with hydroxyl groups, for example of cellulose, or amino and thiol groups, for example of wool and silk, of synthetic polymers, such as polyamides, or else the celluloses aminated according to the present invention, to form a covalent bond, which are particularly suitable. Suitable fiber-reactive components on the textile dyes include in particular sulfatoethylsulfonyl, vinylsulfonyl, 2 1 ~

chlorotriazinyl and fluorotriazinyl and also combinations thereof.

Suitable reactive dyes for dyeing or printing cellulose fibers modified according to the present invention include all water-soluble, preferably anionic, dyes which preferably have one or more sulfo and/or carboxyl groups and which contain fiber-reactive groups. They can belong to the class of the azoic dyes, the class of the direct dyes, the class of the vat dyes, and the class of the acid dyes, be copper complex, cobalt complex and chromium complex azo dyes, copper and nickel phthalocyanine dyes, anthraquinone, copper formazan, azomethine, nitroaryl, dioxazine, triphendioxazine, phenazine and stilbene dyes.
These dyes have been extensively described in the literature, for example in EP-A-0 513 656, and are perfectly familiar to the person ~killed in the art.

Suitable acid or direct dyes for dyeing or printing cellulose fibers modified according to the invention are for example C.I. Acid Black 27 (C.I. No. 26 310), C.I.
Acid Black 35 (C.I. No. 26 320), C.I. Acid Blue 113 (C.I.
No. 26 360), C.I. Direct Orange 49 (C.I. No. 29 050), C.I. Direct Orange 69 (C.I. No. 29 055), C.I. Direct Yellow 34 (C.I. No. 29 060), C.I. Direct Red 79 (C.I. No.
29 065), C.I. Direct Yellow 67 (C.I. No. 29 080), C.I.
Direct Brown 126 (C.I. No. 29085), C.I. Direct Red 84 (C.I. No. 35 760), C.I. Direct Red 80 (C.I. No. 35 780), C.I. Direct Red 194 (C.I. No. 35 785), C.I. Direct Red 81 (C.I. No. 28 160), C.I. Direct Red 32 (C.I. No. 35 790), C.I. Direct Blue 162 (C.I. No. 35 770), C.I. Direct Blue 159 (C.I. No. 35 775), C.I. Direct Black 162:1 and C.I.
Direct Violet 9 (C.I. No. 27 885).

Unless otherwise stated, parts and percentages in the examples which follow are by weight.

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Example 1 A plant-customary fiber grade viscose having a cellulose content of 8.9%, an alkali content of 5% and a viscosity of 38 falling-ball seconds at 30C i8 admixed with an alkaline solution of sheep wool as follows:
6 parts of wool are dissolved in a solution which con-tains 10 parts of sodium hydroxide and 90 parts of water.
Of this solution, 59 parts are mixed with 1000 parts of a plant-customary fiber grade viscose which contains 89 parts of cellulose. After devolatilization the spinning dope is spun by plant-customary viscose spinning processes into a bath which contains sulfuric acid, sodium sulfate and zinc sulfate to form fibers, which are stretched in acid baths, cut, washed, spinfinished and dried.
10 parts of these dry viscose fibers are then admixed in a dyeing apparatus with 100 parts of water. The temperature is raised to 60C and a total of 0.1 part of a 50% strength electrolyte(pre~ominAntly sodium)-contain-ing dye powder of the formula, known from DE-A-l 943 904, 0 ~ N~Z

N~03S SO~N~

is metered in over a period of 30 min. Following a further liquor circulation period of 5 min the remaining, colorless liquor is dropped and the material is conven-tionally washed and dried. The result obtained is a strong and deep red dyeing having very good use fastness properties.

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Example 2 10 parts of the viscose fibers modified and described in Example 1 are transferred into a dyeing apparatus and treated in a liquor ratio of 10:1 with an aqueous liquor which, based on the weight of the dry fibers, contains in solution 0.1 part of a reactive dye of the formula, known from DE-A-24 12 964 o t~H2 SO~N

H~ ~~OSO~Na.
o The fiber mixture is dyed at 60C for 30 minutes. The dyeing thus produced is further treated by rinsing and soaping in a conventional manner. The result obtained is a deep blue dyeing having the usual very good use fast-ness properties.

Example 3 A fiber grade viscose prepared a~ described in Example 1 is spun, after devolatilization, by a plant-customary viscose sp; nn; ng process into a bath containing sulfuric acid, sodium sulfate and zinc sulfate to form fibers, which are stretched in acid baths, cut, washed, ~pinfinished and dried. Weaving gives a textile viscose fabric which can be further processed directly in a pad-dyeing process. For this the fabric ha~ applied to it at 25C an aqueous dye ~olution which, per 1000 parts by volume, contains in solution 20 part~ of the dye of the formula - 9 -21S8~8~

N ~ 0 3 S ~ N~ ~ O C H 3 CH30 o OSO~N~

known from EP-A-0 158 233, Example 1, and 3 parts of a commercial nonionic wetting agent, by means of a pad-mangle to a liquor pickup of 80%, ba~ed on the weight of the fabric. The fabric padded with the dye solution is wound onto a batching roller, wrapped in plastic film, left at from 40 to 50C for 4 hours and then rin~ed with cold and hot water, which may contain a commercial surfactant, and if necessary subseguently rinsed once more with cold water and dried. The result obtained i8 a strong level yellow dyeing which has good all round fastness properties, especially good rub and light fastness properties.

Example 4 A plant-customary fiber grade viscose having a cellulose content of 9%, an alkali content of 5.5% and a viscosity of 40 falling-ball seconds at 30C has an alkaline solution of a commercial gelatin stirred into it as follows:

6 parts of gelatin are dissolved in a solution which contains 10 parts of sodium hydroxide and 90 parts of water. Of this solution, 59 parts are mixed with 1000 parts of a plant-customary fiber grade viscose which contains 89 parts of cellulose. Devolatilization, spin-ning, stretching, cutting, washing and drying affords a fiber which can be dyed by a conventional exhaust process. For this 20 parts of the pretreated viscose fiber are treated in a dyeing apparatus with 200 parts of an aqueous liquor which, based on the weight of the dry 2158~8~

fiber, contains 1.5% of the reactive dye of the formula Na 03SO~ ~ OH
~`N' N~N H ~ c known from EP-A-00 61 151, Example 4, in commercial form and consistency. The fiber i8 dyed with this liquor at 60C for 30 min. The dyeing thus obtained is further treated by rinsing and soaping in a conventional manner.
The result obtained is a vivid orange dyeing having the customary good fastness properties of reactive dyes.

Example 5 A plant-customary fiber grade viscose having a cellulose content of 8.8%, an alkali content of 5% and a viscosity of 41 falling-ball seconds at 30C has an alkaline solution of horsehair stirred into it. For this 8 parts of horsehair are dissolved in a solution which contains 11 parts of sodium hydroxide and 100 parts of water. Of this solution, 65 parts are mixed with 1000 parts of a plant-customary fiber grade viscose which contains 89 parts of cellulose. Further processing by the process steps customary for fiber grade viscoses affords a fiber of modified viscose which can be reactively dyed in an exhaust process without salt and at a pH of 8. For this, 30 parts of viscose fiber are wound onto a package and the yarn is treated in a yarn-dyeing apparatus which contains 450 parts (based on the weight of fiber) of a liquor which contains 0.6 part, based on the initial weight of the fiber, of an electrolyte(pre~s~;nAntly sodium chloride)-containing dye of the general formula - 2 1 ~

S03Na ~N~N~ N~N
N~03S~So NaHN~CoNH F

known from DE-A-28 40 380, Example 1. The pH is adjusted to 8 with sodium bicarbonate. The temperature is raised to 60C, and the liquor is pumped alternately from in to out and from out to in. After 60 min at this temperature, the liquor is dropped, and the dyeing obtained is rinsed and washed according to the customary conditions. The result obtained is a level yellow fiber having the generally good fastness properties of reactive dyes.

Example 6 A plant-customary fiber grade viscose having a cellulose content of 8.9%, an alkali content of 5% and a viscosity of 38 falling-ball seconds at 30C has an alkaline solution of ground horn chips stirred into it as follow~:
7 parts of ground horn chips are dissolved in a solution which contains 11 parts of sodium hydroxide and 100 parts of water. Of this solution, 55 parts are mixed with 1000 part~ of a plant-customary fiber grade viscose which contains 90 parts of cellulose.
Devolatilization, sp; nn; ng, stretching, cutting, washing and drying affords a fiber which can be dyed at pH 4.5 by a customary exhaust process.
For this, 20 parts of the pretreated viscose fiber are treated in a dyeing apparatus with 200 parts of an aqueous liquor which, based on the weight of dry fiber, contains 2% of the direct dye of the formula (C.I. Direct Blue 108, C.I. 51320) 2 ~

Cl El N ~ (S03Nc)3 Et Cl The pH of the liquor is first adjusted to 4.5 with acetic acid. The fiber is dyed with this liquor at 80C for 30 min. The dyeing thus obtained is further treated by rinsing and soaping in a conventional manner. The result is a deep blue dyeing having fastness properties which are far superior to those of conventional direct dyeings.
ThiB i8 true in particular of the wash fastness properties.

Example 7 A plant-customary fiber grade viscose having a cellulose content of 9%, an alkali content of 6% and a viscosity of 42 falling-ball seconds at 30C has an alkaline solution of pig leather stirred into it as follows:
6 parts of pig hide are dissolved in a solution which contains 10 parts of sodium hydroxide and 90 parts of water. Of this solution, 55 parts are mixed with 1000 parts of a plant-customary fiber grade viscose which contains 90 parts of cellulose. The customary process of fibermaking and weaving afford a textile viscose fabric which can be further processed directly in a dyeing process according to the padding principle. For this, an aqueous dye solution which per 1000 parts by volume contains 20 parts of the direct dye of the formula (C.I.
Direct Blue 199) ~S03NH4 CuPc ~(S02NH2)3 (CuPc = copper phthalocyanine) 21~$~8~

and 3 parts of a commercial nonionic wetting agent in BolUtion i8 applied to the fabric at 25C by mean~ of a pad-mangle at a liquor pickup of 80%, ba~ed on the weight of the fabric. The dye solution was fir~t adjusted to pH 5 with acetic acid. The fabric padded with the dye solution i8 then steamed for 2 minutes. The dyeing thus produced is further treated by rinsing and soaping in a conventional manner. The result is a strong tur~uoise dyeing having very good allround fastnesR properties.

Further examples:

The directions of Example 4, 5, 6 or 7 are followed and the modified viscoRe fiber is dyed in accordance with the directions of Example 6 using the below-listed dyes.
Similar result~ are obtained.
C.I. Acid Black 27 NoO~S~H . N ~N N ~NH2 SO~Na C.I. Acid Blue 113 N~03S

~3N N ~N ~ N ~NH
~) ~ SO~Na 21~8~8~

C.I. Direct Orange 49 NoO~S OCH, N~CO SO~Na N N ~ NH - CO - NN ~ N N

SO~No SO~No C.I. Direct Red 79 HoO~5 OCH~ HICO ~ SO~No N ~ NH - CO - NN ~ N N
~ CH~ CH HO ~
boO~S SO~No C.I. Direct Red 84 ~0~5 ~ . co . ~ 0,--~0,~ ~0~

C.I. Direct Red 80 . O ~ . . O

C.I. Direct Red 194 ~ 0, ~ s ~ , 0 "

215~8~ -C.I. Direct Red 32 .. c, ~ .~ .....

C.I. Direct Red 81 NoO35 ~N ~ N ~ ~, NH - C0 C.I. Direct Violet 9 OCH~ HO
N~O~S ~N N ~11 ~l ~NH

S03No R - N ~ N ~NH ~N ~ N - R
where R ~

NaO3S ~N N ~NH - CH2 - COOH

Claims (11)

1. A process for producing aminated regenerated cellu-lose fibers, which comprises preparing a solution of cellulose and a protein having a molecular weight of greater than 50,000 or a natural product comprising such a protein and spinning fibers from this solution.

2. The process of claim 1, wherein a) cellulose and a protein having a molecular weight of greater than 50,000 or a natural product comprising such a protein are mixed and the mixture is alkalized and the resulting alkalized mixture is reacted with carbon disul-fide or b) a protein having a molecular weight of greater than 50,000 or a natural product comprising such a protein is dissolved in sodium hydroxide solution and added to a fiber grade viscose, and the viscose dope obtained from a) or b) is forwarded into an acid spinbath and spun into fibers.

3. The process of claim 1, wherein cellulose and said protein are dissolved in a suitable organic solvent and fibers are spun directly from the solution.

4. The process of at least one of claims 1 to 3, wherein the protein is a keratin, a collagen-con-taining natural product or an albumin.

5. The process of at least one of claims 1 to 4, wherein the protein used comprises body hairs, hides, hooves, horns, claws and nails of mammals, bird feathers, fish scales, spinning threads of insects or gelatin.

6. The process of at least one of claims 1 to 5, wherein the protein is used in an amount of 1 to 20%
by weight, preferably 1 to 12% by weight, based on the cellulose content of the dope.

7. A textile fiber material comprising aminated regenerated cellulose fibers as produced in one or more of claims 1 to 6.

8. A process for dyeing and printing cellulosic textiles with anionic dyes, which comprises perform-ing the dyeing with a dye solution which is free of additional electrolyte salts, at a pH between 4 and 6 in the case of direct and acid dyes and at a pH
between 6 and 8.5 in the case of reactive dyes, while using a textile fiber material as claimed in claim 7.

9. The process of claim 8, wherein the electrolyte content of the dye solution is below 15 g/l.

10. The process of claim 8 or 9, wherein the dyes are reactive dyes.

11. The process of claim 8 or 9, wherein the dyes are acid or direct dyes.