JPH02104774A - Dyeing method using a sulfer dye - Google Patents

Abstract

PURPOSE: To provide a dyeing method for obtaining a uniformly dyed product by continuously applying an aqueous dispersed liquid of a sulfur dye to a substrate by simultaneously and/or subsequently applying a reducing sugar together with alkali thereto, and by subjecting it to heat reduction to prevent e.g. tailing. CONSTITUTION: This method is to apply a continuous dyeing method of e.g. a pad steam dyeing method or pad dry pad steam dyeing method to a substrate comprising a cellulose fiber by employing an aqueous dispersed liquid of sulfur dye using a dispersant of e.g. lignin sulfonate, wherein it is specifically conducted by applying a disperse liquid at 20 to 60 deg.C comprising an alkaline agent (e.g. sodium hydride) and reducing sugar (pref. D-glucose) in the ratio of 50 to 90 g/to the substrate via padding, steam-heating the base material up to 98 to 105 deg.C for reducing the dye, thus dyeing, it, and then oxidizing it for coloring. The method enables any sulfur dye to carry out a continuous dyeing without any listing or tailing.

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to an improved method for dyeing or printing cellulose substrates with sulfur dyes.

More particularly, the present invention relates to continuous dyeing or printing of cellulose substrates with dispersed sulfur dyes.

According to the invention, in dyeing or printing a substrate containing cellulose fibers, a) successively applying an aqueous dispersion of a sulfur dye to the substrate and simultaneously or subsequently applying a reducing sugar together with an alkali, and then b) ) A method is provided that includes heating the substrate to effect reduction of the sulfur dye on the substrate.

Preferably, the temperature for reducing the sulfur dye on the substrate by heating the substrate is 98 to 105°C, more preferably 100 to 103°C.

The substrate to be dyed or printed according to the invention is a substrate containing cellulose fibers. This substrate may be in any form, for example thread, woven or knitted fabric. It may contain only cellulose fibers or it may be a blend of cellulose fibers and constituent fibers such as polyamide, polyester or polyacrylonitrile.

Preferred cellulosic materials include cotton. More preferably, the substrate comprises only cotton or a blend of cotton and polyester.

Preferably, the staining is done by the pad-steam method or by the pad-steam method.
It is carried out using the dry-pad-steam method.

According to the pad-steam method, an aqueous dye solution preferably containing a sulfur dye, reducing sugar and an alkali is used, or a temperature at which the sulfur dye remains in an oxidized state, preferably from 20 to 60
"C1" is more preferably applied at a temperature in the range of 25-50'C. Typically it is padded onto the substrate with a wet pick-up of about 55-70% relative to the weight of the substrate. After the dye solution is applied, the substrate is heated to a temperature high enough to carry out the reduction of the dye, typically 98-105°
c1 Preferably heated to 100-103°C. According to the band-dry-pad-steam method, a dye liquor containing a sulfur dye is applied to the substrate at a temperature of 20-75°C, preferably 30-65°C, to a wet pick-up of typically 55-70%. padding and drying the substrate, then with a solution of reducing sugar in aqueous alkaline, preferably from 90 to
Pad a 120% wet pickup and then heat to reduce the dye.

Printing is carried out in the same manner as the pad-dry-pad-steam method, by printing printing paste onto the substrate instead of padding with a dye liquid.

When the substrate is a cellulosic polyester blend, the band-dry-thermosol-pad-steam method is preferably used. A suitable disperse dye is included in the dye liquor together with the sulfur dye and a thermosol treatment is carried out after the dyeing process. In other words, this method is a pad-dry-pad-
It is similar to the steam method.

As mentioned above, the heating is preferably by steam,
More preferably, the process is carried out in an unpressurized steamer of a normal Paradar steamer, and the substrate is heated with air in the steamer.
The pressure is slightly increased, typically up to about 1,315 atmospheres, sufficient to prevent air pollution.

Heating should be carried out for a period of time long enough to effect complete reduction of the dye on the substrate at the temperature used, but short enough to allow continuous operation in the particular equipment used. Preferably, the heating time is about 20-11
0 seconds, more preferably 40 to 11 seconds, most preferably 40 to 75 seconds.

Staining can be carried out using a conventional continuous dyeing device.

As will be appreciated by those skilled in the art, such conventional equipment includes means such as one or more padders and pressure for sequentially applying the stain and reducing agent to the substrate. Similarly, textile printing can be carried out using conventional printing equipment, including areas where the treated substrate is then heated to reduce the dye, such as a steamer.
Non-pressurized steamer 1 Preferably, this can be done using a steamer specifically designed for steaming prints, in which the printed portion of the substrate does not come into contact with the rollers.

One advantage of the present invention is that dyeing or printing with sulfur dyes can be carried out using reducing sugars, which is safe from an environmental point of view and does not involve the usual pressurization. This can be done using a device.

After the application of the dye liquor or printing paste to the substrate and the reduction of the sulfur dye, it is usually advantageous to subject the substrate thus treated to an oxidation step to further improve the fastness of the dyeing or print. It is. Although certain dyeings and prints will be sufficiently oxidized by the water washing step that usually follows dyeing, it is preferred to carry out chemical oxidation.

Hydrogen peroxide or catalyzed sodium bromate systems can be used. Oxidation conditions may be conventional and will vary depending on the equipment used and the speed of substrate transfer. Generally, for sodium bromate catalyzed by vanadium pentoxide, the amount of this oxidizing agent is usually between 3.75 and 11
．． 25 gel, the pH is preferably 3 to 4.5, and the temperature is usually 45 to 85°C, more preferably 4.
The temperature is 9 to 82°C, more preferably 60 to 75°C.

In the hydrogen peroxide system, about 1 to 5 g/l hydrogen peroxide is used at a pl+ of 5 to 7.5, preferably 5.5 to 6 and a temperature of 35 to 60°C.

Acetic or formic acid is commonly used to bring these systems to the required pH. The substrate is subjected to the action of an oxidizing effective amount of aqueous oxidizing liquid for 5 to 70 seconds, more preferably 10 to 40 seconds.

The dye liquor is preferably prepared by mixing a previously prepared aqueous sulfur dye dispersion with additional water and, when using the Budd-Steam method, with reducing sugars and alkali.

Preferred reducing sugars are carbohydrates or combinations thereof that reduce Fehling's solution, such as aldopentoses such as L-arabinose, D-ribose and D-xylose, D-glucose, D-fructose, D-mannose and O-galactose. These include hexoses, such as hexoses, and dihydrogens such as cellobiose, lactose, and maltose. Products containing reducing sugars such as corn syrup, invert sugar and molasses can also be used, and dextrose is produced from sucrose in the same reaction system. A preferred reducing sugar is D-glucose.

The amount of reducing sugar is sufficient to reduce the sulfur dye when the substrate treated or printed with the dye liquor is heated as described above. Preferably, the reducing sugar is 30 to 135 g#!, whether it is applied from the dye liquor or separately from the alkaline aqueous solution!
, more preferably in an amount of 50 to 120 g/f. Higher amounts may be used, but generally do not improve the quality of the dyeing. Preferably, the reducing sugar is the only reducing agent added to the sulfur dye solution or alkaline aqueous solution.

The alkali may be one known to be effective in reducing sulfur dyes, especially sodium or potassium hydroxide or sodium or potassium carbonate, especially sodium hydroxide. The alkali is preferably so as to give a pi of at least 10, preferably 10.5.
Dyeing solution 1! about 8 to 70 g, more preferably 10 g per i of reducing sugar-containing aqueous liquid applied per or separately
Used in an amount of ~35g.

The dye liquor may contain a wetting agent to improve the penetration of the liquor into the substrate during application.

The particular wetting agent is not limited. Anionic type compounds such as the sodium salt of phosphoric acid-ethylhexanol are preferred. A typical amount of wetting agent is Stain Solution II! ,
The amount ranges from 1 to 15 g per serving.

The aqueous dye liquors used in the puff tote try-pad-steam process preferably contain agents that prevent dye migration during the drying process. Such agents are known;
It may be synthetic, for example based on polyacrylates, or preferably natural, for example based on alginates.

When the dye is applied by printing, conventional thickening agents are used to produce a printing paste with the desired properties.

The aqueous sulfur dye dispersion used to make dye liquors or printing pastes may be a mixture of oxidized sulfur dye in water containing a sufficient amount of dispersant to provide dispersion of the dye in the water. . It is advisable to start with an oxidized sulfur dye presscake, as obtained by conventional thionation, dilution of the thionide with water, oxidation, filtration and washing of the filtercake.

Oxidation (aeration) is preferably carried out until the reaction mixture is free of inorganic sulfides. This point is indicated when the amount of reducing sugar in the reaction mixture becomes zero, which can be determined by potentiometric titration with a 0.2 N cupric ammonium sulfate solution.

The polysulfur content of the dye suspension is also preferably very low, more preferably zero. 0 reduction of suspension I
! Aeration to a certain amount will also reduce the polysulfur content to the desired level. It would be better to perform an experimental aeration to bring the reduction potential to zero and then measure the polysulfur content. This can be done by treating a sample of the product with excess sodium sulfide and then calorimetrically titrating the sample with sodium cyanide. If the polysulfur content is too high, the precipitation step for the individual dyes may be treated before aeration with an amount of sodium sulfite and/or sodium nitrite effective to reduce the polysulfur content. It is preferable to change it to include.

Preferably, aeration is stopped as soon as possible after the sulfide is removed. It has been found that excessive oxidation can lead to the formation of crosslinked polycondensation products which cannot be easily reduced by glucose-caustic alkali and is therefore undesirable in the dyeing and printing process of this invention. Ta. It is advisable to monitor the particle size of the suspension, for example with a particle size analyzer, and stop aeration before an increase in particle size begins to occur.

Preferably, the presscake is washed to remove inorganic salts normally associated with such thionation reaction products. Washing is suitably carried out until the inorganic sulfuric acid content is less than 2% by weight, preferably less than 0.6% by weight, based on the weight of solids in the press cake.

More preferably, washing is carried out until the total inorganic salt content is less than 2% by weight, in particular less than 0.6% by weight.

A convenient way to determine that the salt content has been reduced to the desired level is to measure the conductivity of the wash water used by
For example, it is measured using a Che+wtrix Type 700 conductivity meter. Using this method, cleaning is preferably continued until the conductivity of the rinse water after use is no more than 140, more preferably 60 microohms/cm higher than the conductivity of the rinse water before use.

The press cake has a dye content of the resulting mixture of about 8 to
40, preferably 10-35, more preferably 15-35
Combined with additional water in an amount to be within 35% by weight. The particular dispersant used to produce the dye dispersion is not particularly limited. Product name Vanispers
e CB, Reax@85 A and Reax■P
Various anionic and nonionic surfactant compounds and mixtures thereof, such as sodium lignin sulfonate, sodium salts of polymerized alkylnaphthalene sulfonic acids (e.g. Taa+ol e SN) and mixtures of glycols, commercially available under C946. Good results were obtained using . The amount of dispersant will depend in part on the particular dye being dispersed and will be readily determined by those skilled in the art. Good results have been obtained using 5 to 20% by weight of dispersant, based on the total weight of the dispersion. Other additives such as biocides may be incorporated into the dispersion. Preferably, the components of the dispersion are stirred together and the resulting mixture is milled until a good dispersion is obtained, wherein the dispersed sulfur dye particles are prepared by Microtrac@Particle-S
ize Analyzer (Leeds-North
rup), preferably 0.1 to 5 microns, more preferably 0.3 to 1.5 microns.

The amount of dye dispersion used to make the dye liquor or printing paste will vary depending on the dye content of the dispersion and the desired color density. Usually about 15 to 16 g of dye dispersion are added per 11 dye liquors.

The method of the present invention allows cellulose-containing fibrous materials to be dyed with sulfur dyes which require relatively low reduction potentials for solubilization, such as glucose and sodium hydroxide at concentrations within the aforementioned ranges within 60 seconds at 102°C. It is particularly suitable for dyeing with oxidized sulfur dyes which can be reduced by. Preferred examples of such dyes include C.I. I. Sulfur Black 1 (Structure No. 53185), C.I. I.
Sulfur Black 2 (Structure No. 53195), C.I. I
．． Sulfur Black 18, C.I. Sulfur Green 2 (Structure No. 53571), C9■, Sulfur Green 36 (as described in Example 1 of U.S. Pat. No. 3,338,918), C.I. I. Sulfur Bluff (Structure number 5
3440), C,! , Sulfur Blue 13 (Structure No. 53450), C.I. I. Sulfur Blue 43 (Structure No. 53630), C.I. I. Sulfur Red 10 (Structure No. 5322B), C.I. I. Sulfur Red 14, C
．． I. Sulfur Brown 37 and C. I. It is Sulfur Yellow 22.

Since these dyes are in a water-soluble oxidized state when applied to the substrate in the method according to the invention, they are not direct to cellulose fibers or dye the fibers immediately; Rather, it has the opportunity to become uniformly distributed before becoming direct through the heating process. As a result, problems such as color difference between the center and outside of the fabric and tailing are prevented.

The invention is further illustrated by the following examples. Parts and percentages are by weight.

250 parts crude thionated mass of green sulfur dye prepared according to Example 1 of U.S. Pat. No. 3,338,918 and 480 parts
The aqueous mixture is aerated for 2 hours at 88°C, cooled to 45°C and filtered. filter cake to 65 micro ohms/
The cleaning solution becomes transparent with tap water that has a conductivity of cm.
Wash until it has a conductivity of 110 microohms/cm. 55 with a solids content of 43.2%
A portion of press cake is obtained. Place the following items into a laboratory ball mill.

13.9 parts of the sulfur dye presscake prepared above, 2.4 parts of sodium geninsulfonate (Vanis
perse CB trademark), 1.5 parts of the sodium salt of polymerized alkylnaphthalene sulfonic acid (Taspecial oI S
N trademark), 0.6 parts of diethylene glycol and 2.4 parts,
7. Mixture with 9-tetramethyl-5-decyne-4,6-diol (Sulfynol 104 E Trademark), 0
．． 1 part sodium salt of chlorinated bisphenol (Gi
v-gard G4-40™) and 11.0 parts of water.

The resulting mixture is stirred and then milled for 24 hours to obtain 28.5 parts of the dispersion of the sulfur dye prepared above.

5 parts of the dye dispersion prepared above and 50 parts of water are stirred together until a homogeneous mixture is obtained.

To this mixture are added 12 parts of glucose, 12 parts of aqueous sodium hydroxide (50%), 10 parts of water and 0.5 part of the sodium salt of ethylhexanol phosphate ester. The resulting mixture is stirred for 5 minutes and then diluted to 133 parts with additional water.

The dye liquor obtained above is heated to 43 DEG C. and poured into the dye pan of an Aztec laboratory padder steamer with a non-pressure steamer. A pre-bleached cotton fill fabric is padded through this dyeing solution to a 70-80% wet pick-up, steamed for 60 seconds at 101-103°C and then washed with hot tap water.

An oxidation solution is prepared by adding 7.5 g of hydrogen peroxide (35% solution) and 7.5 g of glacial acetic acid to enough water to give a total volume of 12. Heat this solution to 60°C,
Add the substrate dyed above and stir the solution for 30 seconds. The substrate is then washed with hot tap water and then dried. A uniform green dyeing is obtained.

Flame fork C, T, Sulfur Blue 13 (C, I, structure number 5
1354 parts of water are added to 402 parts of the crude thionized mass of 3450). The resulting mixture is heated at 90° C. for 11 hours until all of the sulfides are completely oxidized (determined by measuring zero reduction potential). The pl+ of the resulting slurry was reduced to 5 by adding 7.5 parts of sulfuric acid (70%).
．． 6 and then filter. The filter cake was washed with tap water, which has a conductivity of 65 microohms/cII+, and the conductivity of the washing water was 110 microohms/c1! 285 parts of filter cake having a solids content of 27.5% are obtained.

Put the following into a ball mill.

203 parts of the sulfur dye filter cake obtained above, 15 parts of sodium geninsulfonate (Vanispers
e CB), 12 parts of sodium salt of polymerized alkylnaphthalene sulfonic acid (Tamol SN), 1 part of 6-acetoxy-2,4-dimethyltodioxa 7 (GIV-GARD DXN Trademark) and 63
Department of water.

The resulting mixture was milled with marble for 24 hours,
It is then milled with sand for 24 hours so that the particle size is in the range of 1-5 microns and then separated from the sand.

An aqueous dye liquor is prepared containing 30 parts of the above dye paste and 15 parts of an alginate-type anti-migration agent per 1000 parts of water. Bleached and mercerized cotton fill was padded with the above liquid into a 60-70% wet pickup at 60°C and dried in an infrared dryer (Fo
Greenville 5teel Te
This material was then steamed with an aqueous solution containing 60 parts of aqueous sodium hydroxide (50%) and 120 parts of dextrose per 1000 parts of water using a padder steamer (serial number 39377) manufactured by xtile Machinery Corp. Pad to 100% wet pick-up at room temperature and then 103% in the non-pressure steaming chamber of the padder steamer.
Steam for 60 seconds at °C.・This material was then washed with water at room temperature and mixed with 7.5 parts of vinegar M per 1000 parts of water.
56%), 7.5 parts of vanadium pentoxide catalyzed sodium bromate and 3.75 parts of a commercially available nonionic scouring agent (Sodyeco@5cour TR) for 30 seconds at 65°C. Perform oxidation scouring. After further washing with water at 65-70°C and then with water at room temperature, a uniform blue dyed product with excellent brightness is obtained.

Claims (1)

[Claims] 1. When dyeing or printing a substrate containing cellulose fibers, a) continuously applying an aqueous dispersion of a sulfur dye to the substrate and simultaneously or subsequently applying reducing sugar together with an alkali; and then b) heating the substrate to effect reduction of the sulfur dye on the substrate. 2. The method of claim 1, wherein the substrate is heated to a temperature of 98-105C for a time sufficient to effect complete reduction of the sulfur dye. 3. The method according to claim 1 or 2, wherein the reduction of the sulfur dye is carried out by heating the substrate in an unpressurized steamer. 4. A method according to any of claims 1 to 3, wherein the sulfur dye is applied to the substrate by padding. 5. The method according to any one of claims 1 to 4, comprising applying to the substrate an aqueous dyeing solution containing a sulfur dye, a reducing sugar and an alkali. 6. A method according to any of claims 1 to 4, comprising applying to the substrate an aqueous stain containing a sulfur dye and then applying a solution of reducing sugar in an aqueous alkaline to the substrate. 7. The method according to any one of claims 1 to 6, wherein the reducing sugar is glucose. 8. The method according to any one of claims 1 to 7, wherein the sulfur dye does not contain inorganic sulfides. 9. Sulfur dye is C. I. Sulfur Black 1, 2 and 18, C.I. I. Sulfur Green 2 and 36, C
．． I. Sulfur Blue 7, 13 and 43, C.I. I.
Sulfur Red 10 and 14, C.I. I. Sulfur Brown 37 and C. I. The method according to any one of claims 1 to 8, wherein the method is selected from the group consisting of Sulfur Yellow 22. 10. The method according to claim 5 or 6, wherein reducing sugar is the only reducing agent added to the staining solution. 11, Claims 1 to 10
A cellulose fiber base material dyed by the method according to any one of the above. 12. 30-135g/ for use in the pad steam application process of claim 5 or the pad dry pad steam application process of claim 6.
1 of reducing sugar and 8-70 g/l of alkali. 13, 50-90 g/l reducing sugar and 10-35 g/l
13. The padding liquid of claim 12, comprising 1 of alkali.