NO141233B - DEVICE FOR LAUNCHING AND SEPARATION OF SEVERAL BODIES FROM A GRANE OR SIMILAR - Google Patents

Description

Procedure for dyeing in a single aqueous dye bath of mixtures of polyester fibers and acrylic fibers.

The present invention relates to a

method for co-dyeing or over-dyeing textiles of mixed fibres, one of which is produced from an aromatic polyester and the other is produced from an acrylic fibre.

The aromatic polyesters to which the invention relates are the highly polymeric esters obtained by heating glycols of the series HO(CH,)nOH, where n is an integer from 2 to 10, together with terephthalic acid or an ester-forming derivative thereof, for example an aliphatic ( including cycloaliphatic) or aryl ester or half ester, an acid halide or an ammonium or amine salt, under conditions which give the esters in a highly polymerized form. Examples of such high polymer linear esters are those obtained by reacting terephthalic acid or an ester-forming derivative thereof and ethylene glycol, trimethylene glycol, tetra-, hexa- or decamethylene glycol. These polyesters are high-melting, poorly soluble and mainly colorless materials, which can be formed into filaments that can be stretched by drawing into strong flexible fibers, which in characteristic X-ray spectra show molecular orientation along the fiber axis. Of these polyesters, polyethylene terephthalate is preferred as this is easily available and has excellent properties as a textile material.

The acrylic fibers used are polymer mixtures where the most important acrylonitrile

polymer is a polymer of at least 80 percent acrylonitrile and smaller amounts of monomers that can be co-polymerized with it.

The second component in the acrylic fiber mixture is a polymer of at least 30 percent of a vinyl pyridine or alkyl substituted vinyl pyridine and up to 70 percent of another copolymerizable monomer. The two components of the polymer mixture are used in such amounts that the mixed acrylic fiber material contains a total of at least 80 percent of acrylonitrile and 2-10 percent of a vinylpyridine, both in polymer form.

Vinylpyridines which can be used for the preparation of the mixed product are vinylpyridines or alkyl-substituted vinylpyridines, e.g. 2-vinylpyridine, 3-vinylpyridine, 4-vinylpyridine, 2-methyl-5-vinylpyridine, 2-vinyl-5-methylpyridine, 2-vinyl-5-ethylpyridine, 2-vinyl-4-methylpyridine, 3-vinyl-5- ethylpyridine, 2,4-dimethyl-6-vinylpyridine, and any other vinylpyridine containing alkyl substituents where the alkyl radical contains up to 4 carbon atoms.

The mixed acrylic copolymers can, in addition to the functional components, acrylonitrile and a vinylpyridine, have one or more components obtained from non-functional monomers which are present as a comonomer together with acrylonitrile in the principal polymer or as a comonomer together with a vinylpyridine in the to-blend polymer. Among the monomers that can be used for the copolymerization with acrylonitrile to produce the fiber-forming polymers, mention can be made of vinyl acetate and other vinyl esters of monocarboxylic acids with up to 4 carbon atoms, methyl methacrylate and other alkyl methacrylates with up to 4 carbon atoms in the alkyl radical , methyl acrylate and other alkyl acrylates with up to 4 carbon atoms in the alkyl group, dimethnyl fumarate and other dialkyl fumarates with up to 4 carbon atoms in the alkyl groups, dimethyl maleate and other dialkyl maleates with up to 4 carbon atoms in the alkyl groups, styrene, α-methyl-styrene and others vinyl- or isopropenyl-substituted aromatic hydrocarbons, vinyl chloroacetate and other vinyl esters of halogen-substituted acetic acids, vinylidene chloride, vinyl chloride and methacrylonitrile. Useful monomers for polymerization together with the basic vinylpyridine monomers are styrene, α-methylstyrene, vinyl chloride, vinylidene chloride, vinyl acetate, acrylonitrile, methacrylonitrile, acrylic acid, methacrylic acid, alkyl acrylates, alkyl methacrylates, vinyl ethers, alkyl crotonates, alkyl maleates and alkyl fumarates.

The above-mentioned acrylic fibers can be dyed with acid dyes. As is known, they have excellent properties in the form of spun yarn and are suitable for mixing with fibers of the polyester type from which very desirable textiles can be produced. Despite the fact that these textiles of mixed fibers are very desirable, they have not yet been used commercially to a significant extent. An obstacle to full commercial application has been the lack of a practical and economical dyeing process, i.e. a method by which the mixture can be conveniently dyed with satisfactory authenticity in all shades.

Co-dyeing or over-dyeing of mixed fibers has been practiced for many years with wool and cotton, wool and rayon, rayon and cellulose acetate, etc. Despite all the knowledge that has been gained in the area over these years, dyeing of mixtures containing polyacrylonitrile and polyester fibers still an overwhelming problem so that even dyeing to light or pastel shades is difficult to achieve.

The difficulties increase greatly with the need to achieve deep or strong color tones and especially when a fast and economical one-bath dyeing method is sought.

The invention thus aims to provide a method for co-dyeing or over-dyeing textile materials comprising polyacrylonitrile fibers in combination with polyester fibres, and a method by which textiles comprising a mixture of polyacrylonitrile fibers and polyester fibers can be dyed to strong color tones. The invention further provides a method for dyeing textiles of acrylonitrile/polyester mixtures with such properties as regards color fastness which are satisfactory for men's clothing. According to the invention, these methods for dyeing textiles of the above-mentioned fiber mixtures can be carried out in a single dye bath.

The method according to the invention is carried out in a simple aqueous dye bath by subjecting the aforementioned textile mixtures to a treatment with highly selective, water-dispersible acetate dyes of the type derived from insoluble azo or anthraquinone dyes and dyes of the well-defined class termed "acid dyes". The dispersed acetate dyes are used to obtain dyeing of the polyester fibers in the mixture, while the acid dyes effect dyeing while obtaining deep color tones of the fibers in the mixture that are produced from acrylonitrile-containing polymers.

It has hitherto been assumed that the conditions required for obtaining deep or strong color tones with strongly acidic dyes are incompatible with the use of any dye of the disperse acetate dyes type in the same dye bath. For example, the use of strongly acidic dyes to achieve strong color tones usually requires an acidic environment with a pH in the vicinity of 2-3. Generally, the disperse acetate dyes become ineffective in the presence of such strong acids. This and other problems are solved according to the present invention, which enables the dyer to use selective acetate dyes together with acid dyes in a single dye bath to achieve a commercially satisfactory strong dyeing of the textiles containing both acrylonitrile and polyester fibers.

The disperse acetate dyes used in the execution of the invention are: "-Celliton Fast Yellow 4 RL" (CI. Disperse Yellow 23), "Resoline Orange GL", "Interchem Acetate Pink DNA", "Latyl Cerise B",

Æatyl Red B", "Resoline Red 3 BL", "Eastman Fast Blue B-GLF" (CI. Disperse Blue 27), "Artisil Direct Yellow RN", "Latyl Violet BN", and "Resoline Blue FBL". Any one or a mixture of any of these dyes may be used. The concentration of the dye can be varied within

wide limits as in conventional dyeing processes. Usually the dye bath contains from approx. 0.01 to 10.0 percent genetic material calculated on the weight of the textile material or its starting material.

In order to facilitate the preferential absorption and penetration of the acetate dye into the polyester fiber of the mixture, it is usually necessary to use a "dye aid" or "carrier". The choice of this component can be made among many different agents that are usually used for this purpose. Examples of this are dimethyl terephthalate, ortho-phenylphenol, phenyl-methylcarbinol, ortho-dichlorobenzene and monochlorobenzene, of which ortho-phenylphenol is preferred. Generally, the best results are obtained when the carrier is used in an amount of about 10 per cent of the weight of the textile material being dyed, although amounts down to approx. 5 percent and up to approx. 25 percent can be used.

As disperse dyes are not soluble in water, they are applied to the fiber in a finely divided, almost colloidal dispersion. To achieve this finely dispersed state of dyes in the aqueous bath, surface-active compounds or dispersants must normally be used. Of these, the well-known anionic substances have been found to be the most suitable for carrying out the invention. Typical examples among the many substances of this type that can be used are the sodium salt of sulphonated alkyl or aryl hydrocarbons, the sodium salt of sulphated fatty alcohols and diisobutyl sodium sulphosuccinate. Generally, good results are obtained when the anionic dispersant is used in an amount of from 0.2 to 1.0 percent calculated on the weight of the textile material, and preferably approx. 0.5 percent

While the number of usable acetate dyes is limited, virtually any dye from the general group of "acid dyes" can be used in the present process. Among the many usable dyes of the aforementioned group can be mentioned: "Neolan Blue 2G" (CI. Acid Blue 158A), "Xylene Light Red 2GL"

(CI. Acid Red 37), "Xylene Yellow 2G"

(CI. Acid Yellow 17), "Chromolan Red 3RB" (CI. Acid Red 207), "Alizarine Light Blue B" (CI. Acid Blue 45) and "Neolan Yellow GR" (CI. Yellow 99). A single dye or a mixture of acid dyes can be used, and the dye can be varied widely as in the case of the acetate dye. The amount required for a specific dyeing will of course depend on the depth of color desired.

According to a preferred sequence of steps for carrying out the invention, a mixed textile material of the above type is immersed in an aqueous bath where the weight ratio between water and textile material is approx. 40 : 1. The dispersant and the selected dyeing aid are then added to the dye bath. The temperature is raised to approx. 50° C, and the textile material is circulated in the bath for approx. 10 minutes. The water-dispersible acetate dye is added and circulated for a short time, usually approx. 10 minutes. The temperature is then raised slowly to approx. 82° C, after which the bath cools down to approx. 66° CDs are now added with sufficient sulfuric acid or an equivalent to bring the pH of the dye bath within the range of 2-3. The dye bath is allowed to continue to cool until the temperature is approx. 60° C, after which an aqueous solution containing the acidic dye is added. After a short period of continued circulation, the dye bath temperature is slowly raised during approx. 45 minutes to approx. 99° C, which temperature is maintained for approx. 60 minutes. Thus, the normal dyeing operation is finished; however, additional dye can be added if necessary to achieve the desired color tones. If and when this is done, the bath temperature should not be higher than 82° C during the addition. When the desired color tone has been achieved, the bath is cooled to 71° C with subsequent rinsing. The colored article is then washed in the usual way at approx. 60° C with a diluted solution of detergent and alkali.

It will be clear to a person skilled in the art that the conditions including treatment times, temperatures, concentrations, etc. as mentioned above, can be varied to a considerable extent, likewise that the order of steps can be varied. For example, a modification where all dyes and dyeing aids are added to the bath at the same time will be fully usable. However, it has been found that the best results are obtained when the disperse acetate dye is added to the bath before the acid dye.

The following examples will further illustrate the invention. All parts are parts by weight and all percentages are based on the dry weight of the article being dyed, unless otherwise stated.

Example I.

A portion by weight of a textile material containing equal parts of a polyester fiber and an acrylic fiber containing mainly mixed polymers consisting of 89 percent acrylonitrile and 6 percent 2-methyl-5-vinyl-pyridine was placed in an aqueous dye bath containing 40 parts water. The bath was then supplemented with 0.5 percent of a commercial dispersant

agent consisting of a modified sodium

salt of sulphonated hydrocarbons, as well as 10

% of a dyeing aid or

rer consisting of dimethyl terephthalate. The temperature was then set at 49°C, and the bath was circulated for 10 minutes. The somewhat cooled bath was reheated to 49° C, after which the following disperse acetate dyes were added: 1.90 percent "Latyl Cerise B" and 0.02 percent "Artisil Direct Yel-

loy RN". After this addition, the bath temperature was slowly raised to 82° C,

after which the heat supply was interrupted and ba-

it allowed to cool. At a temperature of

66° C, 6 per cent of a diluted solution of sulfuric acid was added there, after which the pH of the bath was between 2 and 3. The bath was allowed to cool further, and at a temperature of 60° C

the following acid dyes were added:

2.0% "Neolan Blue 2G" (CI. Acid Blue 158A), 0.90% "Xylene Light Red GL"

(CI. Acid Red 37) and 1.40 percent "Xylene Light Yellow 2G" (CI. Acid Yellow 17). After

After 10 minutes of circulation of the bath, the temperature was slowly raised to 99° C. during 45 minutes, which temperature was maintained for 60 minutes. The bath was then cooled to 71° C with subsequent rinsing. The father-

The article was then washed at 60°C

with a solution of 1.0 percent polyethylene glycol oleyl ether and 0.50 percent trisodium phosphate

barrel. Finally, the dyed textile material

alet rinsed and dried. A deep red and black overdyeing tone was obtained without stains. The color fastness met the standard requirements

vein for commercial menswear.

Example II.

The procedure according to the previous example was repeated using the same acid dyes, but with the following disperse acetate dyes in the amounts given for those in example I an-

turned: 0.12 percent "Eastman Fast Blue B-

CLF" (CI. Disperse Blue 37), 0.28 percent "La-

tyl Violet BN", 0.36 percent "Interchem Ace-

tate Pink DNA" and 0.40 percent "Celliton Fast Yellow 4RL".

After dyeing, rinsing and drying

the material had a brown and black over-staining color tone without stains. color fidelity

ten satisfied the requirements for menswear.

Example III.

The procedure according to example I was repeated with the exception that

therefore, the disperse acetates used there

dyes used the following dyes-

from the same general group: 2.0 per cent.

"Eastman Fast Blue B-GLF" (CI. Disperse Blue 27), 0.7% "Resoline Blue FBL", 0.6

percent "Resoline Red 3 BL", and 2.4 percent "Re-

soline Orange GL".

The colored textile material had a

heavy brown and black over-dye

tone without blemishes. The color fastness satisfied

set the requirements for menswear.

Example IV.

The method according to example I was

followed by dyeing a textile material containing a 30/70 mixture of a polyester fiber and an acrylic fiber. The method used was as indicated in example I with the exception that they used there

disperse acetate dyes were replaced with 0.55% "Eastman Fast Blue B-GLF"

(CI. Disperse Blue 27), and 0.01 percent "Latyl Red B".

The colored textile material had a

blue and black overdye tint without stains. The color fastness satisfied the standard requirements for men's clothing.

The present invention provides a commercially acceptable process for dyeing

ning of textile materials containing a mixture of polyester and polyacrylonitrile fibres. The process gives dyeing to deep color tones that are characterized by good equalization, freedom from stains and a color fastness that satisfies the fairly high standard requirements for men's clothing. Furthermore, the process can be carried out in a single dye bath,

which is a particularly appealing feature from a commercial point of view. Although there has been considerable commercial interest in fiber blends of polyester fibers and acid-

dyeable polyacrylonitrile fibers and such mixed

dinger's possibilities, so far it has not been possible to dye such mixtures to deep colors

vetones by a one-bath method.

The method according to the invention satisfies this need and makes it

it is possible that such materials can enter the market.

Claims (4)

1. Procedure for dyeing in a single aqueous dye bath of mixtures of polyester fibers and acrylic fibers where acrylfib- pure are obtained from a mixture of polymers or copolymers of acrylonitrile and polymers or copolymers of a vinylpyridine and contain at least 80 wt. acrylonitrile and from 2 to 10 percent vinylpyridine, characterized in that the mixture is dyed with at least one acid dye and at least one water-dispersible acetate dye of the type derived from insoluble azo or anthraquinone dyes, the dyeing as known per se is carried out in the presence of a carrier and an anionic dispersant, and where the pH of the dye bath is kept between 2 and 3. 2. Method according to claim 1, characterized in that the carrier is orthophenylphenol. 3. Method according to claim 1, characterized in that the mixture of fibers is first subjected to dyeing with at least one of the acetate dyes in the presence of a carrier and an anionic dispersant, whereupon the pH of the bath is set to a value between 2 and 3, after which the acid dye is added, and that, after the dyeing with these introduced dyes has ended, further amounts of acetate dye or acid dye are added. 4. Method according to claim 3, characterized in that the weight ratio between said mixture and water in the aqueous dye bath is 1:40.