JP2024510904A - Formaldehyde-free aqueous composition for fabric discharge printing - Google Patents

Abstract

The present invention relates to a composition for discharge printing of fabric, a discharge printing method for printing said composition on fabric, use of the composition for discharge printing, and a fabric treated with the composition in the discharge printing method according to the invention. .

Description

The present invention relates to a formaldehyde-free aqueous composition for discharge printing of dyed fabrics, to its use and method of production, and to a discharge printing method.

Discharge printing relates to special printing methods for bleaching or coloring fabrics. The key element in discharge printing is the discharge composition containing a reducing agent. Discharge printing starts from a colored fabric that has been colored with a dye. Dyes are sensitive to reducing agents and degrade upon treatment with discharge compositions containing reducing agents. The discharge composition is printed onto a fabric and the dye of the fabric is extracted within the printed pattern area. In this way, it is possible to produce a printed fabric with a white pattern in which the natural color of the fabric becomes visible. In other applications, the printing composition further comprises pigments that are resistant to reducing agents. In this way, a colored discharge printed fabric is obtained in which the color of the resistant pigment is overlaid on the bleached printed pattern. Commonly known reducing agents useful for discharge printing are Rongalit ST fluid and/or Rongalit C powder, both based on sodium formaldehyde sulfoxylate derivatives. The printing compositions used for discharge printing generally contain further constituents such as thickeners, binders and auxiliaries such as softeners, emulsifiers, crosslinkers, rheology modifiers and pigment preparations.

Known discharge printing processes require a steam treatment and a curing process step after the printing step in order to destroy the residues of the discharged dye and formaldehyde-containing reducing agent. The discharge process involves further process steps including a fixing process step for fixing the binder and a final cleaning step to remove all chemical residues including formaldehyde.

A problem with existing systems and processes is that customers often complain about formaldehyde odors during drying, steaming, and fixing processes when using common discharge printing compositions and processes. Additionally, brand manufacturers are exploring more environmentally sustainable systems and processes that do not emit formaldehyde. Therefore, discharge printing processes have been developed in which the steam treatment step is avoided. These processes are known as dry discharge printing. However, the reducing agents used in these processes still utilize formaldehyde zinc sulfoxylate derivatives. These reducing agents are characterized by a high reducing effect, which also leads to an undesirable deterioration of the thickeners necessarily used in printing paste compositions. As a result, the viscosity of the printing paste often has a tendency to deviate from the specification range, which is a disadvantage in industrial discharge printing processes. To overcome these drawbacks, alternative used thickeners have been used that resist the reducing effects of formaldehyde zinc sulfoxylate derivatives. However, these thickeners require more complex printing compositions and higher costs.

Therefore, the object of the present invention is to discharge print fabrics avoiding the use of reducing agents containing formaldehyde, reducing complexity and process time, and maintaining the stability of the printing paste during the printing process, Another object of the present invention is to provide a composition that can improve the printing quality of discharge printed fabric.

This objective is solved by the following items:

Item 1: In formaldehyde-free aqueous compositions for discharge printing of fabrics, at least one reducing agent, at least one synthetic thickener, at least one wetting agent, at least one pH adjusting agent, optionally at least one A composition comprising a pigment and optionally at least one binder.

Item 2: Composition according to item 1, wherein the at least one synthetic thickener is a polyacrylic compound, preferably selected from acrylic acid copolymers, preferably comprising a dense oil and an auxiliary agent.

Item 3: Item wherein at least one binder is based on a copolymer of two or more of poly(butyl acrylate), butyl(acrylate), ethyl(acrylate) and styrene, polyvinyl acrylate, acrylonitrile or mixtures thereof. 1. The composition according to at least one of 2.

Item 4: Composition according to at least one of items 1 to 3, wherein the humectant is selected from urea, glycerin or mixtures thereof.

Item 5: The composition according to at least one of items 1 to 4, wherein the reducing agent comprises or consists of a sulfinic acid derivative.

Item 6: The composition of items 1 to 5 further comprising one or more components selected from the group consisting of crosslinkers, softeners, emulsifiers, defoamers, rheology modifiers and antioxidants or mixtures thereof. A composition according to at least one of the above.

Item 7: The composition according to at least one of items 1 to 6, wherein the composition does not contain any natural thickeners.

Item 8: 3-30% by weight of at least one reducing agent, 0.05-6% by weight of at least one synthetic thickener, 3-45% by weight of at least one wetting agent, 0.05-4 % by weight of at least one pH regulator, 0-30% by weight of at least one binder, 0-2% by weight of at least one emulsifier, 0-1% by weight of at least one defoamer, 0-3% by weight. % of at least one crosslinker, 0-3% by weight of at least one softener, 0-2% by weight of at least one rheology modifier, 0-2% by weight of at least one antioxidant, 0-6% by weight. % of at least one pigment dispersion, the balance up to 100% by weight being water, where the weight % is based on the total weight of the composition. Composition.

Item 9: A method for producing a composition according to at least one of items 1 to 8, comprising the following step A and optionally steps B and C:
Step A: For the composition according to at least one of items 1 to 8, excluding at least one pigment, if at least one pigment is present in the composition according to at least one of items 1 to 8. Step B: Adding at least one dispersion comprising at least one pigment to the mixture obtained in Step A; Step C: Mixture obtained in Step B. Mix and homogenize.

Item 10: Use of a formaldehyde-free aqueous composition according to at least one of items 1 to 8 for a fabric discharge printing process, in particular a white discharge printing process or a colored discharge printing process, or according to the process defined in item 9. Use of manufactured formaldehyde-free aqueous compositions.

Item 11: Step 1: Providing a colored fabric, Step 2: Printing, i.e. printing a fabric using the formaldehyde-free aqueous composition according to at least one of items 1 to 8 or item 9. Printing a fabric with the thus produced formaldehyde-free aqueous composition, step 3: a first drying step, i.e. drying the fabric obtained in step 2, step 4: a washing step, i.e. washing the fabric obtained in step 3, wherein the fabric is rinsed with a rinsing fluid and/or soaped with a soaping fluid; step 5: a second drying step, i.e. the fabric obtained in step 4; A discharge printing method for printing a fabric, including a drying step.

Item 12: The washing step comprises a first cold and/or hot rinsing step in which the printed fabric is rinsed with a rinsing fluid selected from cold water or an aqueous H ₂ O ₂ solution, and/or the printed fabric a hot soaping step in which the fabric is washed with a soaping fluid selected from soapy water at a temperature of 40-80°C, and/or the printed fabric is rinsed with a second rinsing fluid selected from cold water. a second low temperature rinsing step.

Item 13: The first drying step is carried out at a temperature of 140°C to 180°C, preferably for 1 to 5 minutes, and/or the second drying step is carried out at a temperature of 120°C to 160°C, preferably The method according to at least one of items 11 or 12, which is carried out for 8 to 20 minutes.

Item 14: The method according to at least one of items 11 to 13, which does not include a curing step and/or a steam treatment step.

Item 15: Fabric treated with the composition according to at least one of items 1 to 8 or the composition obtained according to item 9 in the discharge printing method according to at least one of items 11 to 14.

In a first aspect, in a formaldehyde-free aqueous composition for discharge printing of fabrics, at least one reducing agent, at least one synthetic thickener, at least one wetting agent, at least one pH adjusting agent, optionally The problem is solved by a composition comprising at least one pigment and optionally at least one binder.

The composition has the advantage of being formaldehyde-free. Therefore, no formaldehyde is released in the discharge printing process using the composition according to the invention. The odor and dangerous effects of formaldehyde are thus eliminated. The term "formaldehyde-free" within the context of this application means that no formaldehyde residues are detectable when measured according to AATCC 112, according to commonly known measurement methods. . Furthermore, the composition according to the invention has the advantage of improving the print quality in the discharge printing process.

The term "reducing agent" as used within the context of this application means an agent capable of reducing reactive dyes. At least one reducing agent present in the composition according to the invention comprises or is constituted by a sulfinic acid derivative. The at least one reducing agent does not include any formaldehyde releasing compounds or moieties. It has been observed that the sulfinic acid derivatives can be used to efficiently treat fabrics within a discharge printing process. Furthermore, the process time and energy consumption of discharge printing processes utilizing the compositions of the present invention are significantly reduced, since the discharge printed fabric does not need to be treated in an additional curing step as is done in conventional discharge printing processes. It was also observed that

Another advantage of the compositions according to the invention is that they are easy to prepare. Preparation of the composition according to the invention can be carried out at the customer's facility. Due to the reducing strength of the at least one reducing agent, additional steaming steps commonly used in known discharge printing processes can also be avoided. With the use of the composition according to the invention, the extraction effect on the dye is already achieved using hot air. Furthermore, another advantage is that, in the case of the compositions according to the invention, there are fewer adverse effects observed on colored pigments. Because of this advantage, it is possible to achieve more vivid shading through the printing process.

Within the context of this application, the term "sulfinic acid derivative" means a reducing agent comprising or consisting of one or more sulfinic acid derivative compounds. For example, sulfinic acid derivatives of _the formula RSO(OX) can be used, where X means a cation that balances the anionic charge of RSO(O) ^- , H, an alkali metal cation, R ¹⁴ N ⁺ where R ¹ means H, C ₁ -C ₄ alkyl or mixtures thereof; where R means an alkyl or aryl residue which may be further substituted. A typical sulfinic acid derivative used in the composition according to the invention is sold under the trade name Rongalit® ECO.

In order to have a bleach extraction effect on the dye of the fabric in the discharge printing process, the reducing agent needs to have a certain redox potential. The term "redox potential" is well known in the art. It describes the ability of a compound to transfer/accept electrons in a chemical reaction between electron acceptor/donor compounds. Redox potential is determined by using standard hydrogen electrodes or other standard electrodes. The redox potential of the sulfinic acid derivative used as reducing agent in the composition according to the invention is at least 800 mV, or at least 825 mV, or at least 850 mV. The redox potential should be at most 1000 mV, or at most 975 mV or at most 950 mV. In preferred embodiments, the reduction potential of the sulfinic acid derivative is between 800 mV and 1000 mV, or between 825 and 975 mV, or between 850 and 950 mV.

At least one sulfinic acid derivative reducing agent is present in the composition according to the invention in an amount of at least 3%, or at least 6%, or at least 7%, or at least 8%, or at least 9% by weight. This amount is at most 30%, or at most 25%, or at most 20%, or at most 15%, or at most 13% by weight. Preferably, the amount of at least one reducing agent in the composition according to the invention is from 3 to 30% by weight, or from 6 to 25%, or from 7 to 20%, or from 8 to 15%, or from 5 to 15% by weight. % by weight, or within the range of 9-13% by weight. The amounts in % by weight are based in each case on the total weight of the composition according to the invention.

The term "fabric" as used within the context of this application refers generally to "fibers", "mixed fibres", "yarns", "knitted fabrics", "non-woven fabrics" and "woven fabrics". means a specific term. Preferably, the fabric used according to the invention comprises or is composed of cellulose fibers. The term "mixed fiber" as used within the context of this application means that at least two fibers are combined into one mixed fiber by commonly known spinning methods, where: The at least two fibers are made of different materials, i.e. at least one fiber is made of or consists of cellulose and the second fiber is made of or consists of polyamide, silk or wool. The term mixed fibers used within the context of this application therefore means a combination of at least two fibers, one fiber made of cellulose and the second fiber made of polyamide, silk, wool.

The term "woven fabric" as used within the context of this application means a two-dimensional or three-dimensional fabric made from yarn by a weaving process. The yarn used to bring it into the woven state may be composed of fibers or mixed fibers as defined above. The term "yarn" as used within the context of the present invention means an agglomeration of fibers according to the invention, an agglomeration of mixed fibers as defined above, where the agglomeration is achieved by a spinning process. This means that the yarn may contain two or more of the mixed fibers defined above, depending on the desired yarn properties such as strength or thickness.

The term "nonwoven fabric" as used within the context of the present invention refers to a two-dimensional or three-dimensional fabric made of yarns bonded by chemical means, mechanical means, heat or solvent treatment, i.e. by a method different from the weaving method. means the fabric of The yarns used for the production of non-woven fabrics are composed of fibers or mixed fibers as defined above.

The term "knitted fabric" as used within the context of the present invention means a two-dimensional or three-dimensional fabric made from yarns as defined above by a braiding process.

The fabric material used for discharge printing preferably contains or consists of cellulose, preferably cotton and/or viscose.

The fabric used in the discharge printing according to the present invention is usually pre-dyed with a background dye. The term "ground dye" as used within the context of the present invention refers to a fabric completely or partially dyed with one or more dyes that are sensitive to the reducing effect imparted by at least one reducing agent. means to be Suitable dyes used as extractable ground dyes usually contain azo groups which are decomposed upon treatment with a sulfinic acid derivative reducing agent so that an extractable effect can be observed. Such dyes are generally known as reactive dyes.

The term "reactive dye" as used within the context of the present invention means "fiber-reactive azo dye" or "vinylsulfone dye". Reactive dyes are well known in the art. Reactive dyes are defined by the ability of the chromophore of the dye to react with textile substrates such as mixed fibers, yarns, woven, non-woven and knitted fabrics made of or containing cellulose, polyamides, silk, wool, etc. It is characterized by containing one or more substituents having the following. Reactive dyes are a class of organic dyes that contain at least one substituent that reacts with the substrate and thus forms a covalent bond between the substrate to be colored and the dye molecule. For example, WO 2007/039573 A2 relates to azo-reactive dyes and mixtures of fiber-reactive azo dyes, processes for their preparation, and their use for dyeing and printing hydroxyl- and carboxamide-containing materials. Furthermore, WO 2004/088031 likewise discloses mixtures of azo-reactive dyes and fiber-reactive dyes, their preparation and their use. WO 2015/149940 relates to compounds obtained by coupling two aminoaryl compounds in cyazotized form onto 3-aminophenyl urea. These compounds are used as azo-reactive dyes in dyeing and printing processes. Examples of reactive dyes for dyeing fabrics to be treated with the composition according to the invention are Reactive Red 35, Reactive Red 106, Reactive Orange 13, Reactive Blue 250, Reactive blue 28, Reactive Yellow w 15, Reactive Yellow 43 or Reactive Black 5.

The term "discharge printing" as used within the context of the present invention means dyed, ie colored Refers to a method of extracting or removing color from fabric. According to the invention, the composition for discharge printing can be used in the form of a paste. According to the invention, at least one composition according to the invention is used for extracting color from fabrics. Optionally, additional pigments that are resistant to sulfinic acid derivative reducing agents may also be included in the composition according to the invention in such a way that coloring of the discharged areas on the fabric is achieved. During the printing process, a discharge composition is applied to the colored fabric to effect color extraction. The term "extraction" within the context of this application means that the ground dye of the fabric is bleached. "Bleaching" in this context means that the color of the background dye is faded by treatment with a sulfinic acid derivative reducing agent. A favorable bleaching effect is achieved when the ground dye is completely faded.

There are many methods for printing fabrics known in the art, such as block printing, perotene printing, roller printing, cylinder printing or machine printing, paper pattern printing, screen printing or flat printing, digital textile printing, flexo textile printing, etc. exist. The compositions according to the invention are suitable for use in all known methods for printing fabrics, in particular for printing woven, non-woven and knitted fabrics. The printing process or printed fabric is characterized in particular by the application of a certain pattern or design to the fabric. The term "printed" as used within the context of the present invention therefore means a fabric that has been subjected to the printing process as defined above by extracting the ground dye from the fabric. The term "printed" likewise means that the ground dye extracted is replaced by a pigment that is refractory to at least one reducing agent of the composition according to the invention and thus recolors the fabric. It means a cloth that is made of cloth. Pigment-free discharge printing processes are also referred to as "white discharge printing." Discharge printing processes involving pigments are also called "color discharge printing."

Furthermore, the composition according to the invention comprises at least one synthetic thickener. Thickeners are used to increase the desired final viscosity level of the composition so that the printed pattern shape can be maintained with high definition and flushing of colored water can be avoided. .

The desired viscosity of the composition according to the invention is at least 3,000 mPa·s or at least 3,500 mPa·s or at least 3800 mPa·s. The viscosity of the composition should be at most 5000 mPa·s or at most 4500 mPa·s or at most 4,200 mPa·s. The preferred viscosity range of the composition according to the invention is 3,000 mPa·s to 5000 mPa·s, or 3,500 mPa·s to 4,500 mPa·s or 3,800 mPa·s to 4,200 mPa·s. Typical thickeners used in textile printing processes are characterized by their viscosity increasing behavior. Basically, in textile printing natural and synthetic thickeners are used for the printing process. However, from the point of view of the compositions according to the invention, natural thickeners have the disadvantage that the viscosity increase behavior is delayed and low. Therefore, changing the viscosity of natural thickeners in printing compositions to the desired final level can take an undesirably long time. Therefore, for the composition according to the invention, the processability of the discharge printing process using natural thickeners is significantly impaired. On the contrary, the synthetic thickeners used in the compositions according to the invention, which are based on polymers obtained from acrylic acid and its derivatives, are preferred for the claimed discharge printing process. The desired viscosity level of the composition according to the invention increases within 1 hour, preferably within 40 minutes, more preferably within 30 minutes. Therefore, the processability of the extraction process is dramatically increased compared to processes using natural thickener products. The viscosity properties of liquids or amorphous solids are primarily generated by interparticle forces within the solution, including friction and attraction between molecules within the macrostructure. These van der Waals forces are a crucial aspect of a sample's resistance to deformation or flow, and define the viscosity of the material. Dynamic viscosity represents a measure of the shear stress per unit area required before the sample begins to deform. Viscosity is typically expressed in millipascal seconds, mPa·s. A standard test method for determining dynamic viscosity and density of liquids is performed on a Stabinger viscometer according to ASTM D7042.

At least one synthetic thickener is present in the composition according to the invention at least 0.05% by weight, or at least 0.5% by weight, or at least 1% by weight, or at least 1.5% by weight, or at least 1% by weight. Present in an amount of .8% by weight. The amount of at least one synthetic thickener in the composition according to the invention may be at most 6% by weight, or at most 5% by weight, or at most 4% by weight, or at most 3% by weight, or at most 2% by weight. .3% by weight. Preferably, the amount of at least one synthetic thickener in the composition according to the invention is between 0.05 and 6% by weight, or between 0.5 and 5%, or between 0.5 and 4%, or between 1 and 5% by weight. 4% by weight, or from 1.5 to 3% by weight, or from 1.8 to 2.3% by weight. The amounts in % by weight are in each case based on the total weight of the composition according to the invention.

The synthetic thickeners used in the compositions according to the invention are furthermore characterized in that they do not react adversely with the at least one reducing agent. Discharged fabrics exhibit high color yields, gloss and flatness and can be printed with very fine screens that allow for prints with no spotting problems, ie sharply defined prints. In general, the viscosity-increasing effectiveness of the above-mentioned synthetic thickeners in the drawing compositions according to the invention is improved compared to natural thickeners. It is therefore possible to use less of the thickener than a natural thickener while achieving the same viscosity of the discharge composition. The term "synthetic thickener" as used within the context of the present invention has no natural origin. That is, it refers to thickeners that are not derived from plant, algal or animal products, ie compounds that have the ability to increase the desired viscosity level of a liquid composition. In one embodiment, the at least one thickener is a polyacrylic compound, i.e. one or more of acrylic acid and acrylic esters, wherein the at least one synthetic thickener is a copolymer based on acrylic acid monomers or derivatives thereof. A polymer or copolymer constructed from derivatives of. Synthetic thickeners are preferably used as inverse emulsions of copolymers based on acrylic monomers or derivatives thereof in oil which swell and increase viscosity when combined with water. Preferably, the synthetic thickener comprises a dense oil and/or an auxiliary agent, such as a nonionic surfactant. Suitable synthetic thickeners are known under the trade names Lutexal, Lyoprint, Tubivis, Printex, Uniprint.

In one preferred embodiment of the first aspect of the invention, the composition does not contain any natural thickeners. Natural thickeners, such as alginates or guar-based natural thickeners, can reduce the long time required to increase the final viscosity level in order to apply the discharge composition homogeneously on the fabric. tend to require it. Therefore, the process time of the discharge printing process becomes significantly longer if natural derivatives are used in the composition according to the invention. The term "natural thickener" as used within the context of the present invention means a thickener of natural origin, for example derived from guar beans, algae or animal products.

The composition according to the invention further optionally comprises at least one binder. The at least one binder has the advantage of forming a film on the fabric to which it is applied. By film formation, at least one pigment optionally present in the composition according to the invention is fixed onto the fabric. Therefore, under the term "binder" as used within the context of the present invention, a component is defined as having the ability to form a film on the fabric with which it is assembled, thereby fixing the pigment onto the substrate. should be understood as having. The binder optionally present in the composition according to the invention is designed as an aqueous dispersion comprising a liquid medium and polymer particles dispersed therein. The liquid medium includes or consists of water, one or more surfactants or mixtures thereof. Preferably, the liquid medium does not contain any organic solvent. This has the advantage that the binder is then less flammable. The polymer particles dispersed in the liquid medium have an average particle size of 120-300 nm. The polymer particles are responsible for film formation. The liquid medium is a reactive medium for forming the polymer particles and serves as a stabilizer for the polymer particles dispersed therein during transportation and storage. Polymer particles dispersed in a liquid medium are produced by emulsion polymerization. The monomers to make up the polymer particles are dispersed in a liquid medium and polymerization is initiated using free radical polymerization. Suitable monomers are unsaturated monomers selected from the group comprising vinyl chloride, dichloroethane, acrylic acid, methacrylic acid, acrylamide, acrylonitrile, acrylic esters, vinyl esters, styrene, diolefins such as butadiene, or mixtures thereof. It is monoma. The binder in particular comprises a large amount of polymer particles, at least 35% by weight, or at least 40% by weight, or at least 45% by weight or at most 50% by weight, based on the total weight of the binder, where 100% by weight The remainder up to % is made up of the liquid medium which is water, surfactant or mixtures thereof. As mentioned above, the binder used in the composition according to the invention, as defined above, is designed as a dispersion and therefore comprises or consists of polymer particles dispersed in a liquid medium. present in the composition according to the invention as a dispersion. Film formation on the substrate to which the binder (or in this case the composition according to the invention) is applied occurs once the substrate has been subjected to a heating step, in particular a drying step. The liquid medium is then removed, for example by evaporation, and the previously dispersed polymer particles solidify and flow together, forming a three-dimensional network, or film, in which the pigment is trapped. Since the film has a three-dimensional network structure, fixing of the film on the substrate, in particular on the fabric, is achieved. As a result, another advantage of the binder is that it ensures that the captured pigment has high color fastness to fast rubbing and cleaning operations. Suitable polymers are, for example, poly(butyl acrylate), copolymers of butyl(acrylate), ethyl(acrylate) and styrene, polyvinyl acrylate, acrylonitrile or mixtures thereof. Suitable binders are known under the trade names Helizarin (acrylic vinyl copolymer aqueous dispersion), Cresacryl, Unicryl or Tubifast. If at least one binder is present in the composition according to the invention, its amount is at least 2.5% by weight, or at least 5% by weight, or at least 10% by weight, or at least 15% by weight. If a binder is present in the composition according to the invention, the amount is at most 30%, or at most 25%, or at most 20%, or 19% by weight. Preferably, if a binder is present in the composition according to the invention, the amount of binder in the composition according to the invention is between 2.5 and 30% by weight, or between 5 and 25% by weight, or It is in the range of 5 to 19%, or 10 to 20%, or 15 to 20% by weight. In each case, the amounts in % by weight are based on the total weight of the composition according to the invention.

The composition according to the invention comprises at least one humectant. In the context of this application, the term "wetting agent" means a hygroscopic compound. The wetting agent used in the composition according to the invention avoids too rapid drying of the fabric treated within the discharge printing process. Although the composition according to the invention reduces the overall drying time since higher drying temperatures can be applied, extraction of the ground dye from the fabric requires a humid environment. Therefore, drying the discharged areas on the fabric too quickly can result in incomplete discharge effects. Preferred wetting agents are urea and glycerin. Additional humectants are glycols, polyglycols and salts. In one embodiment, urea is used as a wetting agent. In another embodiment, preferably a mixture of urine and glycerin is used as a wetting agent.

The wetting agent is present in the composition according to the invention in an amount of at least 3%, or at least 5%, or at least 10%, or at least 15%, or at least 20%. The amount of wetting agent in the composition according to the invention is at most 45% by weight, or at most 40% by weight, or at most 35% by weight, or at most 30% by weight. Preferably the amount of wetting agent in the composition according to the invention is in the range from 3 to 45%, or from 5 to 40%, or from 10 to 35%, or from 15 to 30% by weight. The amounts in % by weight are in each case based on the total weight of the composition according to the invention.

In a preferred embodiment, in which the composition according to the invention comprises urea and glycerin as wetting agents, the amount of urea present in the composition according to the invention is at least 0.5% by weight, or at least 2% by weight, or at least 5% or at least 10% by weight. In that case the amount of urea is at most 30% by weight, or at most 25% by weight or at most 20% by weight. Preferably, the amount of urea in that case is from 0.5% to 30%, or from 2% to 25%, or from 10% to 20%. The amounts in % by weight are in each case based on the total weight of the composition according to the invention. The amount of glycerin present in the composition according to the invention is then at least 0.1% by weight, or at least 1% by weight, or at least 3% by weight. The amount of glycerin in that case is at most 15% by weight, or at most 10% by weight, or at most 5% by weight. Preferably, the amount of glycerin in that case is from 0.1% to 15%, or from 2% to 10%, or from 3% to 5%, or from 1 to 5%. The amounts in % by weight are in each case based on the total weight of the composition according to the invention. However, in any case the total combined weight of glycerin and urea is not less than 3% and at most 45% by weight.

The composition according to the invention comprises at least one pH adjusting agent. pH adjusting agents assist in maintaining the pH value of the composition within a defined range. Within a defined pH value range, the thickener is stabilized and the homogeneity of the composition is maintained. The preferred pH value of the composition according to the invention is within the range of pH 8 to pH 9. Preferred pH adjusting agents are selected among tertiary amines, ammonia or ammonium salts and derivatives thereof, which are preferably volatile upon drying of the fabric. A preferred pH adjusting agent is triethanolamine. At least one pH adjusting agent is present in the composition according to the invention in an amount of at least 0.05% by weight, or at least 0.1% by weight, or at least 0.5% by weight, or at least 0.75% by weight. exist. The pH adjusting agent is present in the composition according to the invention in an amount of at most 4%, or at most 2%, or at most 1%, or at most 1.25% by weight. Preferably, the amount of pH adjusting agent in the composition according to the invention is between 0.05 and 4% by weight, or between 0.1 and 2%, or between 0.5 and 1%, or between 0.75 and 1. 25% by weight, or within the range of 0.1-0.4% by weight. The amounts in % by weight are in each case based on the total weight of the composition according to the invention.

The composition according to the invention is an aqueous composition, the balance up to 100% by weight being water. The composition according to the invention is preferably applied to fabrics as a printing paste. A certain amount of fluid carrier is therefore required in order to be able to provide a homogeneous printing paste in which all the required compounds are homogeneously dispersed. The term "fluid carrier" as used within the context of the present invention is defined as having the ability to impart fluid properties to the composition according to the present invention, allowing the components of the printing paste to be printed homogeneously on the fabric. means a liquid that causes According to the invention, water is used as one fluid carrier.

The composition according to the invention optionally comprises at least one pigment. At least one pigment may be added to the composition according to the invention in the form of a pigment dispersion. The composition according to the invention may therefore comprise at least one dispersion comprising at least one pigment. If at least one pigment is used in the composition, the colored extraction areas on the fabric are instantly colored with the pigment during the printing process. If a pigment is present in the composition according to the invention, it is fixed to the fabric by means of a binder and the fabric is thus (re)colored, so that at least one of the pigments as defined herein Two binders are present as well. The pigment utilized in the color extraction process according to the invention must be resistant to at least one reducing agent. Typical pigments useful within the scope of the invention are anthraquinones, phthalocyanines, those of the triphenylmethane type, carbon black, inorganic pigments, quinacridones, monoazo and diazo pigments. In the compositions desired for colored discharge printing according to the invention, at least one pigment dispersion is present in the composition at least 0.01% by weight, or at least 0.02% by weight, or at least 0.5% by weight. %, or at least 1% by weight. In one embodiment, the amount of at least one pigment dispersion in the composition according to the invention is at most 6% by weight, or at most 5% by weight, or at most 4% by weight, or at most 3% by weight. be. Preferably, the amount of at least one pigment dispersion in the composition according to the invention is from 0.01 to 6% by weight or from 0.02% to 5% by weight, or from 0.5% to 4% by weight, Or within the range of 1% to 3% by weight. The amounts in % by weight are in each case based on the total weight of the composition according to the invention.

According to the first aspect of the invention, the composition further comprises one or more selected from the group comprising crosslinkers, softeners, emulsifiers, antifoam agents, rheology modifiers and antioxidants or mixtures thereof. may contain additives.

The crosslinking agent enables fixation of the pigment to the fabric during the color discharge printing process. Therefore, the color fastness of the dyed fabric is improved. The crosslinking agent may be present in the composition according to the invention in an amount of at least 0.1%, or at least 0.2%, or at least 0.5%, or at least 0.75% by weight. The crosslinking agent may be present in the composition according to the invention in an amount of at most 3%, or at most 2.5%, or at most 2%, or at most 1.5% by weight. Preferably, the amount of crosslinking agent in the composition according to the invention is from 0 to 3% by weight, or from 0.1% to 3%, or from 0.2% to 2.5%, or from 0.5% by weight. It is within the range of 0.75% to 1.5% by weight, or 0.75% to 1.5% by weight. The amounts in % by weight are in each case based on the total weight of the composition according to the invention. A suitable crosslinking agent has the trade name Luprintol® Fixing Agent SE. 01 liq.

Softeners impart a smooth feel to fabrics treated in the discharge printing process. The softeners used in the compositions according to the invention are silicon-based. The softener may be present in the composition according to the invention in an amount of at least 0.1%, or at least 0.2%, or at least 0.5%, or at least 0.75% by weight. The softener may be present in the composition according to the invention in an amount of at most 3%, or at most 2.5%, or at most 2%, or at most 1.5% by weight. Preferably, the amount of softener in the composition according to the invention is from 0 to 3% by weight or from 0.1% to 3% by weight, or from 0.2% to 2.5% by weight, 0.2% by weight % to 2.0%, or 0.5% to 2%, or 0.75% to 1.5% by weight. The amounts in % by weight are in each case based on the total weight of the composition according to the invention. A suitable softener is known under the trade name Luprintol® Soft VSN liq.

Emulsifiers make it possible to provide the composition according to the invention as an emulsion, in particular a stable emulsion. Some of the components of the composition according to the invention are themselves provided by the manufacturer in emulsified form. Emulsifiers combine components provided in emulsified form to form a combined main emulsion. Therefore, it is possible to homogeneously disperse each constituent component within the main emulsion, thereby making it possible to produce a homogeneous and precise printed pattern. At least one emulsifier is present in the composition according to the invention in an amount of at least 0.05% by weight, or at least 0.1% by weight, or at least 0.3% by weight, or at least 0.5% by weight. obtain. The emulsifier may be present in the composition according to the invention in an amount of at most 2%, or at most 1.5%, or at most 1%, or at most 0.8% by weight. Preferably, the amount of at least one emulsifier in the composition according to the invention is from 0 to 2% by weight or from 0.05% to 2% by weight, or from 0.1% to 1.5% by weight, or from 0 to 2% by weight. .3% to 1% by weight, or 0.5% to 0.8% by weight. The amounts in % by weight are in each case based on the total weight of the composition according to the invention. A suitable emulsifier is known under the trade name Luprintol® Emulsifier PE new liq c. .

Antifoaming agents prevent the disadvantageous effects of air bubble formation during the production of the composition according to the invention and/or during discharge printing using said composition. Foaming tends to make the composition for discharge printing non-homogeneous and thus can result in non-uniform print patterns on the fabric. The antifoam agent may be present in the composition according to the invention in an amount of at least 0.05% by weight, or at least 0.1% by weight, or at least 0.15% by weight. The antifoam agent is present in the composition according to the invention in an amount of at most 1% by weight, or at most 0.8% by weight, or at most 0.4% by weight, or at most 0.3% by weight. It is possible. Preferably, the amount of antifoam agent in the composition according to the invention is between 0 and 1% by weight, or between 0.05% and 1% by weight, or between 0.1% and 0.8% by weight, or between 0. It is in the range of 1% to 0.4%, or 0.15% to 0.3% by weight. The amounts in % by weight are in each case based on the total weight of the composition according to the invention. A suitable defoamer is known under the trade name Antimussol® UDF (1:10).

Rheology modifiers improve the surface tension of the compositions according to the invention. Additionally, rheology modifiers improve the stability of thickeners. In practice, therefore, the stability of the printing surface on the fabric is improved. Preferred rheology modifiers used in the compositions according to the invention are polyacrylate copolymer emulsifiers or polyurethane dispersions or mixtures thereof. At least one rheology modifier is present in the composition according to the invention in an amount of at least 0.05% by weight, or at least 0.1% by weight, or at least 0.15% by weight, or at least 0.3% by weight. It can exist. At least one rheology modifier is present in the composition according to the invention in an amount of at most 2% by weight, or at most 1.5% by weight, or at most 1% by weight, or at most 0.8% by weight. It can exist. Preferably, the amount of rheology modifier in the composition according to the invention is between 0 and 2% by weight, or between 0.05% and 2%, or between 0.1% and 1.5%, or between 0. In the range of 15% to 1%, or 0.2% to 1%, or 0.3% to 0.8% by weight. The amounts in % by weight are in each case based on the total weight of the composition according to the invention. A suitable rheology modifier is known under the trade name Luprintol Additive RM 01 liq.

Antioxidants protect the pigments used in the compositions according to the invention from oxidation during printing and drying. In practice, a reduction in yellowing during the discharge printing process is achieved and the quality of the printed image is improved when antioxidants are used in the composition. A preferred antioxidant used in the composition according to the invention is m-nitro-benzenesulfonate or its derivatives. At least one antioxidant is present in the composition according to the invention at least 0.05% by weight, or at least 0.1% by weight, or at least 0.2% by weight, or at least 0.3% by weight, or at least Present in an amount of 0.5% by weight. At least one antioxidant is present in the composition according to the invention in an amount of at most 2% by weight, or at most 1.5% by weight, or at most 1% by weight, or at most 0.8% by weight. It can exist. Preferably, the amount of at least one antioxidant in the composition according to the invention is from 0 to 2% by weight or from 0.05% to 2% by weight, or from 0.1% to 1.5% by weight, or 0.2% to 1.5% by weight, or 0.3% to 1% by weight, or 0.3% to 0.8% by weight, or 0.5% to 1.5% by weight. within range. The amounts in % by weight are in each case based on the total weight of the composition according to the invention. A suitable antioxidant is known under the trade name Revatol NS liq.

According to a first aspect of the invention, the composition comprises:
3-30% by weight of at least one reducing agent,
0.05% to 6% by weight of at least one synthetic thickener;
3-45% by weight of at least one wetting agent;
0.05 to 4% by weight of at least one pH adjuster;
0-30% by weight of at least one binder,
0-2% by weight of at least one emulsifier,
0 to 1% by weight of at least one antifoaming agent,
0-3% by weight of at least one crosslinker,
0-3% by weight of at least one softener;
0-2% by weight of at least one rheology modifier,
0-2% by weight of at least one antioxidant;
0 to 6% by weight of at least one pigment dispersion;
containing or consisting of these, with the balance up to 100% by weight water;
The weight percentages here are based on the total weight of the composition according to the invention.

Furthermore, the composition according to the present invention includes
3-30% by weight of at least one reducing agent;
0.05% to 6% by weight of at least one synthetic thickener;
3-45% by weight of at least one wetting agent;
0.05 to 4% by weight of at least one pH regulator;
0.05-2% by weight of at least one emulsifier,
0.05-1% by weight of at least one antifoaming agent;
0.1 to 3% by weight of at least one crosslinker,
0.1 to 3% by weight of at least one softener;
0.05-2% by weight of at least one rheology modifier,
0.05-2% by weight of at least one antioxidant, and optionally
0.01 to 6% by weight of at least one pigment dispersion;
2.5-30% by weight of at least one binder;
or consisting of water, with the balance up to 100% by weight being water;
The weight percentages herein are based on the total weight of the composition.

Furthermore, the composition according to the present invention
5-15% by weight of at least one reducing agent,
1% to 4% by weight of at least one synthetic thickener;
10-30% by weight of at least one wetting agent,
0.2-2% by weight of at least one pH regulator;
0.05-2% by weight of at least one emulsifier,
0.1 to 0.4% by weight of at least one antifoaming agent;
0.5-2% by weight of at least one crosslinker,
0.2-2% by weight of at least one softener;
0.2-1% by weight of at least one rheology modifier,
0.2-1.5% by weight of at least one antioxidant, and optionally
0.5 to 4% by weight of at least one pigment dispersion;
5-19% by weight of at least one binder;
or consisting of water, with the balance up to 100% by weight being water;
The weight percentages here are based on the total weight of the composition according to the invention.

In a second aspect, the invention relates to a method for manufacturing a discharge printing composition according to the first aspect of the invention. Accordingly, the details, definitions and limitations set out above with respect to the composition according to the first aspect of the invention also apply in the method according to the second aspect of the invention. The method according to the invention comprises or consists of the following step A and optionally steps B and C:
Step A: If at least one pigment is present in the composition according to at least one of the invention, excluding at least one pigment according to at least one of the embodiments of the first aspect of the invention. mixing and homogenizing all components for the composition of
Step B: Adding at least one dispersion comprising said at least one pigment to the mixture obtained in Step A; and Step C: Mixing and homogenizing the mixture obtained in Step B.

In step A, all components for the composition according to the invention are mixed and homogenized, with the exception of the optional at least one pigment. The composition obtained in step A results in a composition according to the invention suitable for white discharge printing. The composition may be in the form of a paste. The mixing and homogenizing step consists of mixing and homogenizing the components, in particular in equipment traditionally used for mixing and homogenizing the components for pastes, in particular pastes for discharge printing. It can be implemented with The preferred equipment for step A is a supershear mixing blade. Mixing and homogenization of the components can be carried out for any suitable amount of time and at any suitable stirring rate, such as from 200 rpm to 4000 rpm for 5 to 30 minutes.

Optional step B comprises the addition of at least one pigment, which can be added to the mixture obtained in step A as a pigment-containing dispersion. It is possible to perform step B immediately after step A. It is likewise possible to subject the mixture obtained in step A to step B after storing it for a certain period of time. Furthermore, it is possible to add further constituents to the composition obtained in step A. It is likewise possible to premix further constituents with the at least one pigment added to the mixture obtained in step A.

Optional step C includes mixing and homogenizing the mixture obtained in step B. The composition obtained in step C results in a composition according to the invention suitable for colored discharge printing. The mixing and homogenizing step consists of mixing and homogenizing the components, in particular in equipment traditionally used for mixing and homogenizing the components for pastes, in particular pastes for discharge printing. It can be implemented with The preferred equipment for step C is a high speed kneader. It is possible to perform step C immediately after step B. It is likewise possible to subject the mixture obtained in step B to step C after storage for a certain period of time. Once step C is completed, the composition according to the invention is ready for use, i.e. ready to be applied to fabrics. Preferably, the composition according to the invention is designed to become a paste for discharge printing after completion of step C.

Optional steps B and C are performed in the case of a colored discharge printing process. Optional step B may be performed before or concurrently with step A.

Furthermore, it is possible to carry out additional steps before step A, after step C or between steps A, B and/or C. Possible steps are, for example, a heating step, a cooling step, a sieving step.

In a third aspect, the invention relates to the use of a composition according to the first aspect of the invention, or to the second aspect of the invention, for a fabric discharge printing process, in particular a white discharge printing process or a colored discharge printing process. It relates to the use of formaldehyde-free aqueous compositions prepared according to such a method. Accordingly, the details, definitions and limitations explained above with respect to the compositions according to the first aspect of the invention and the second aspect of the invention also apply in the use according to the third aspect of the invention. Preferably, the fabric used comprises or is composed of cellulosic fibers such as cotton.

The term "white discharge printing process" used within the context of the present invention means a printing process in which a printing composition without any pigment is used for discharge printing. Thus, printed fabrics are characterized by color extraction within the printed areas, where the natural color of the fabric fibers becomes visible.

The term "pigmented discharge printing process" used within the context of the present invention means a printing process in which at least one pigment is used for discharge printing. The printed fabric is characterized in that the areas from which the color has been extracted are overlaid, ie colored or dyed with the color of the pigment.

In a fourth aspect, the invention relates to a discharge printing method for textile printing. The details, definitions and limitations set out above in relation to the first aspect of the invention, the second aspect of the invention and the third aspect of the invention also apply in the discharge printing method according to the fourth aspect of the invention. Ru. The discharge printing method according to the invention comprises or consists of the following steps:
Step 1: Providing a colored fabric;
Step 2: Printing step, i.e. printing a fabric with a formaldehyde-free aqueous composition according to the first aspect of the invention or a formaldehyde-free aqueous composition prepared according to the second aspect of the invention. The step of printing the fabric using a material,
Step 3: first drying step, i.e. drying the fabric obtained in step 2;
Step 4: washing step, i.e. washing the fabric obtained in step 3, in which the fabric is rinsed with a rinsing fluid and/or soaped with a soaping fluid;
Step 5: Second drying step, ie drying the fabric obtained in step 4.

The discharge printing method according to the invention does not require an additional steam treatment process step as is the case with discharge printing methods known in the art. Process time and energy consumption are therefore significantly reduced compared to known discharge printing methods. The discharge printing method according to the invention does not use any formaldehyde releasing agents. In particular, the composition, rinsing fluid, cleaning fluid and optional finishing agent according to the first aspect of the invention is free of formaldehyde releasing agents. Therefore, no malodor or harmful burden on the environment is generated during the discharge printing method according to the invention. Furthermore, it has been observed that the long and intensive washing steps utilized in discharge printing methods known in the art to remove formaldehyde residues can be reduced.

The composition according to the first aspect of the invention or produced according to the method of the second aspect of the invention used in the discharge printing method according to the fourth aspect of the invention is preferably designed as a paste. be done. Printing may be carried out by conventional printing methods known in the art for printing fabrics, for example by rotary or flat printing machines.

After drying, the printed fabric is subjected to a washing step for washing the fabric in step 4. The fabric is rinsed with a rinsing fluid and/or soaped with a soaping fluid to remove components of the printing paste. The term "rinsing fluid" within the context of this application means a fluid that has the ability to flush solid and/or soluble residues from the fabric remaining after the first drying according to step 3 on the fabric. . Preferably, the rinsing fluid is water or based on an aqueous H ₂ O ₂ solution. In one embodiment, the fabric is rinsed with water and/or soaped with a soaping fluid to remove components of the printing paste. The term "soaping fluid" means an aqueous fluid for removing from the fabric any lipophilic residue remaining on the fabric after the first drying step according to step 3. Typically, soaping fluids are based on aqueous fluids containing detergents. The washing step may include one or more of the following steps: cold rinsing, warm rinsing, and/or hot soaping. A washing step can be carried out immediately after the first drying step. It is likewise possible to store the printed fabric after the first drying step for a certain period of time before being subjected to the washing step.

After washing, the printed fabric is subjected to a second drying step. The cleaned fabric is therefore provided in dry form and can be subjected to possible further processing steps, such as finishing steps. Other possible steps such as heating, cooling, pressing, etc. can be carried out to bring the printed fabric into a ready-to-use shape.

The discharge printing method according to the present invention includes, as step 4, a cleaning process that includes or consists of the following steps:
a first cold and/or hot rinsing step, in which the printed fabric is rinsed with a rinsing fluid selected from cold water or an aqueous H ₂ O ₂ solution;
a high temperature soaping step and/or in which the printed fabric is washed with a soaping fluid selected from soapy water at a temperature of 40-80°C;
A second cold rinsing step in which the printed fabric is rinsed with a second rinsing fluid selected from cold water.

The printed fabric may be rinsed with a rinsing fluid comprising water or an aqueous H ₂ O ₂ solution. Thus, the water-soluble components remaining on the printed fabric after the first drying step are released from the printed fabric. In a preferred embodiment, the fluid in the first rinsing step comprises H ₂ O ₂ . The H ₂ O ₂ degrades residues from the at least one reducing agent remaining on the printed fabric after the first drying step.

In the soaping step, the printed fabric is soaped with a hot soaping fluid. The printed fabric is then thus freed from the lipophilic residues remaining on the printed fabric after the first drying step. High temperature soaping of the printed fabric is preferably carried out at 40-80°C. More preferably soaping is carried out at 50-75°C or 60-75°C. Preferably, the soaping fluid contains a non-ionic soaping agent, such as is commercially known as Imerol Jet-B liq c.

A second rinsing step follows the hot soaping step. A second rinsing step is performed using cold water, which removes any residue from the soaping step. After the second rinsing step, the printed fabric is cleaned and further subjected to the second drying step described above.

Furthermore, the discharge printing method according to the invention comprises step 3, i.e. a first drying step carried out at a temperature from at least 140°C, or at least 145°C, or at least 150°C, or at least 155°C or at least 155°C. . The temperature should be at most 180°C, or at most 175°C, or at most 165°C. In preferred embodiments, the temperature is between 140°C and 180°C, or between 145°C and 175°C, or between 150°C and 170°C, or between 155°C and 165°C. The dry conditions allow rapid effect of white extraction on the fabric. When compositions containing pigments are used, high color fixation of the pigments is achieved. The drying time of the first drying step is set to at least 1 minute, or at least 2 minutes and at most 5 minutes or at most 4 minutes. Preferably, the drying time is 1 to 5 minutes, or 2 to 4 minutes.

The discharge printing method according to the invention comprises step 5, a second drying step carried out at a temperature from at least 120°C, or at least 125°C, or at least 130°C, or at least 135°C. The temperature of the second drying step should be at most 160°C, or at most 155°C, or at most 150°C. In preferred embodiments, the temperature in the second drying step is between 120°C and 160°C, or between 125°C and 155°C, or between 130°C and 150°C, or between 135°C and 145°C. The drying time in the second drying step is set to at least 8 minutes, or at least 10 minutes, or at least 12 minutes and at most 20 minutes or at most 18 minutes. Preferably, the drying time is 8 to 20 minutes, or 10 to 20 minutes, or 12 to 18 minutes.

For industrial implementation of the method, the fabric can be provided as a fabric web. The fabric web can be stored on fabric rolls. According to a fourth aspect of the invention, a fabric web is unwound from a fabric roll, conveyed to one or more steps of a discharge printing process, and then rewound into a fabric web.

According to a fourth aspect of the invention, the discharge printing method may be carried out such that the printing (step 2) and the first drying (step 3) of the fabric web are carried out in an in-line process, wherein the fabric web is Preferably, the web is passed through a printing unit in which a printing step (step 2) is carried out and a first drying unit in which a first drying of the fabric web (step 3) is carried out. The web is run through the printing unit and the first drying unit at a conveyor speed of 10 to 30 m/min.

Within the context of this application, the term "printing unit" refers to a printing unit constructed to transport a fabric web through a printing unit and applied to the invention on a fabric to carry out a printing step (step 2) in a discharge printing process. By this we mean a printing machine which is further constructed in such a way as to apply such a printing composition. Within the context of this application, the term "drying unit" means a drying oven capable of applying drying and heating conditions to a fabric web, and further includes a drying oven in which the fabric web is conveyed through the drying unit. It is constructed in such a way that it can be

According to a fourth aspect of the invention, the discharge printing method is carried out in such a way that it does not include a curing process. According to the present invention, it has been found that such a curing process is not necessary to produce a superior printed fabric. As a result, the process time and energy consumption of the discharge printing method according to the invention is significantly reduced. _CO2 emissions, energy consumption and process times are reduced by 10%, or 20%, or 25% compared to commonly known and practiced discharge printing methods using commonly known discharge printing compositions. A reduction of 30%, or 35%, or 40% or even 45% is possible. Curing process steps utilized in the prior art include treating the fabric with hot air. Furthermore, the method according to the invention does not use any steam treatment process that is typically carried out using saturated steam at high temperatures.

A fifth aspect of the invention provides a composition according to at least one embodiment of the first aspect of the invention or a second embodiment of the invention in a discharge printing method according to at least one embodiment of the fourth aspect of the invention. The present invention relates to a fabric treated with a composition obtained according to an embodiment of the present invention. The effect observed on fabrics worked according to the invention should be seen in the improvement of the gloss of white discharge printed and colored discharge printed fabrics. The gloss of fabrics worked according to the invention is improved compared to comparison fabrics worked according to the extraction process used in the art.

Furthermore, fabrics worked according to the color extraction method according to the invention exhibit higher levels of color fixation than comparative examples worked according to the known discharge printing method.

In this regard, reference is made to FIGS. 1 and 2.

FIG. 1 shows a fabric sample treated in a color extraction method according to the invention using a composition according to the invention and, as a comparison, a fabric sample treated in a benchmark method using a benchmark composition. Figure 1 demonstrates the higher color fastness of fabric samples worked according to the invention. Figure 2a shows a white drawn fabric sample and a colored drawn sample worked in the drawing process according to the invention using compositions for white and colored discharge printing, respectively, according to the invention. Figure 2b shows white discharge printing, each worked according to a benchmark extraction method known in the art, using benchmark compositions for white discharge printing and colored discharge printing, respectively, also as known in the art. An extracted fabric sample and a colored extracted fabric sample are shown.

Example 1: Preparation of a composition according to the invention for discharge printing In a first step A, a mixing vessel equipped with a blade stirrer is filled with stirring according to the specifications given in Table 1. Did:

1.1 Composition for white discharge printing After the subsequent mixing of components 1 to 12 and 14, stirring was continued for a further 20 minutes at 2000 revolutions/min until a final viscosity of 3,500 mPa·s was reached. The pH value of the composition was pH=8.5.

1.2 Composition for colored discharge printing After subsequent mixing of components 1 to 12 and 14, stirring was continued for a further 20 minutes until a final viscosity of 3,500 mPa·s was reached. The pH value of the composition was pH=8.6.

In the second step B, the dispersion containing the pigment PrintofixT-B was added to the composition obtained in the first step A under stirring.

In the third step C, the mixture from step B was mixed and homogenized under stirring.

Comparative Example 1: Benchmark Composition Zinc formaldehyde sulfoxylate and a natural thickener were used in place of the reducing agent and thickener of Example 1, as commonly used in the art for discharge printing processes. Benchmark components containing agents were prepared.

In the first step A, the mixing vessel was filled with stirring according to the specifications shown in Table 2:

1.1 Composition for white discharge printing After the subsequent mixing of components 1 to 5 and 7, stirring was continued for a further 10 hours at 2000 revolutions/min until a final viscosity of 3,500 mPa·s was reached.

1.2 Composition for colored discharge printing After subsequent mixing of components 1 to 5 and 7, stirring was continued for a further 10 hours until a final viscosity of 3,500 mPa·s was achieved.

In the second step B, the dispersion containing the pigment Printofix T-B was added to the composition obtained in the first step A under stirring.

In the third step C, the mixture from step B was mixed and homogenized under stirring.

Example 2: Discharge printing method according to the present invention A 100 gr/m ² cotton sateen fabric which had been ground dyed was provided.
2.1 White Extracted Fabric The fabric was provided as a fabric web wound onto a fabric roll. The fabric was unwound and guided through the printing unit at a conveyor speed of 20 m/min. In the printing unit, the printing composition obtained in Example 1.1 was applied to the fabric by a conventional flat screen printing method (J. Zimmer, GmbH; Austria-Mini MDF/796). After running through the printing unit, the fabric was conveyed to the drying unit. Drying and fixing of the print was done by drying at 160° C. for 2 minutes. The fabric web was transported from the drying unit and rewound onto a fabric roll. Thereafter, the printed fabric web was washed. The fabric web roll was unwound and the fabric web was conveyed through the washing unit at a conveyor speed of 40 m/min. In the washing unit, the fabric was cold rinsed with water and then rinsed with 1 g/l aqueous H ₂ O ₂ (w:v) at 40° C. and 60° C. for 10 minutes each. The fabric web was then washed for 10 minutes in soapy water at 70° C. containing 1 g/l (w:v) of an anionic soaping agent (Kieralon Jet B conc.liq.). The fabric web was then rinsed with cold water for 10 minutes, air dried, and re-wound onto a fabric roll.

2.2. Colored Extraction Fabric The process of Example 2.1, except that instead of the composition obtained in Preparation Example 1.1, the composition obtained according to Example 1.2 was used in the discharge printing process. repeated.

Comparative Example 2: Benchmark Printing Process A benchmark printing process was carried out as commonly applied in the art.
2.1. White Extracted Fabric The background-dyed dyed fabric of Example 2 was provided as a fabric web wound onto a fabric roll. The fabric was unwound and guided through the printing unit at a conveyor speed of 20 m/min. In the printing unit, the printing composition obtained in Comparative Example 1.1 was applied to the fabric by a conventional flat screen printing method (J. Zimmer, GmbH; Austria-Mini MDF/796). After running through the printing unit, the fabric was conveyed to the drying unit. Drying and fixing of the print was performed by drying at 135°C for 1 minute, steaming at 102°C for 10 minutes, and curing at 150°C for 5 minutes. The fabric web was transported from the drying unit and rewound onto a fabric roll. Thereafter, the printed fabric web was washed. The fabric web roll was unwound and the fabric web was conveyed through the washing unit at a conveyor speed of 20 m/min. In the washing unit, the fabric was cold rinsed with water and then rinsed with 1 g/l aqueous H ₂ O ₂ (w:v) at 40° C. and 60° C. for 10 minutes each. The fabric web was then washed for 20 minutes in soapy water at 70° C. containing 1 g/l (w:v) of an anionic soaping agent (Kieralon Jet B conc.liq.). The fabric web was then rinsed with cold water for 30 minutes, air dried, and rewound onto a fabric roll. The number of washes required is at least two as far as Example 2.1 is concerned.

2.2. Colored discharge fabric Comparative Example 2.1, except that instead of the composition obtained in Comparative Example 1.1, the composition obtained according to Comparative Example 1.2 was used in the discharge printing process. Repeated the process.

Examples 2.1 and 2.2 and Examples 2.1 and 2.2 with respect to the desired evaluation parameters of the printing process according to the invention, namely contamination of zinc derivatives, formaldehyde emission, energy consumption and process time. compared.

Zinc evolution was determined according to EN16711-2:2016. Formaldehyde evolution was determined according to AATCC112. The data in Table 3 show that no zinc or formaldehyde contamination could be detected for the printing method according to the invention. Furthermore, according to the textile printing method according to the present invention, energy consumption and process time can be reduced by approximately half.

Example 3: Color fastness and color intensity of fabric samples worked according to the invention 3.1 Fabric samples printed according to the color extraction process of Example 2.2 were prepared and their friction dyeing An investigation was conducted due to its fastness.

Fabric samples prepared according to Example 2.2 were home laundered at 60°C. These samples were then subjected to dry and wet rub fastness measurements according to ISO 105/X12.

The fabric sample exhibited a dry rub fastness rating of 4.2 and a wet rub fastness rating of 2.9.

3.2 The relative color strength (K/S) of the printed fabric was measured by light reflectance using the Kubelka-Munk equation. The reflectance (R) of the printed fabric was measured on a Konica Minolta MF-3700d (Japan). It was determined that the color intensity of the sample was increased by at least 27% compared to Comparative Example 3 below.

Comparative Example 3: Color fastness and color intensity of fabric samples worked according to the benchmark method 3.1 Fabric samples printed according to the color extraction process of Example 2.2 were prepared and their abrasion An investigation was conducted due to color fastness.

Fabric samples prepared according to Comparative Example 2.2 were home laundered at 60°C. These samples were then subjected to dry and wet rub fastness according to ISO 105/X12.

The fabric sample exhibited a dry rub fastness rating of 3.2 and a wet rub fastness rating of 2.4.

3.2 The relative color depth (K/S) of the printed fabric was measured by the reflectance of light using the Kubelka-Munk equation, and the reflectance (R) of the printed fabric was measured by Konica Minolta. Measured on MF-3700d (Japan).

The test results of Example 3 and Comparative Example 3 are shown in FIG. As can be seen from Figure 1, the dry and wet rub color fastness of fabric samples worked according to the invention is clearly improved compared to the color fastness levels achieved by the benchmark extraction process. Furthermore, as is evident from FIG. 1, the color intensity of the sample worked according to Example 3 was more pronounced than that of the sample worked according to Comparative Example 3.

Example 4: Quality of Extraction, Sharpness and Gloss Fabric samples worked according to Example 2.1, Example 2.2 and comparative fabric samples worked according to Comparative Examples 2.1 and 2.2. Comparisons were made regarding extraction quality, sharpness and gloss. A visual inspection was carried out of a sample worked according to the invention as shown in Figure 2a and a sample worked according to the known benchmark method and composition as shown in Figure 2b. The following was observed:
- The white sample worked according to Example 2.1 shows significantly less yellowing than the white sample worked according to Comparative Example 2.1. The quality of discharge printing, ie bleaching, achieved with the composition and method according to the invention is therefore improved compared to known benchmark systems.
- The colored pull-out sample worked according to Example 2.2 was identified as having a brighter color appearance compared to the colored pull-out sample worked according to Comparative Example 2.2. The color gloss of the samples worked according to Example 2.2 is improved compared to the benchmark samples. Without being bound by theory, the compositions and printing methods of the present invention produce less dye/pigment degradation compared to known benchmark systems.
- A sharper print pattern was observed for the white extraction and colored extraction samples worked according to Examples 2.1 and 2.2 compared to the samples worked according to Examples 2.1 and 2.2. It was done. Therefore, the sharpness quality of the samples worked according to the invention is improved compared to the comparative examples.

1.2 Composition for Pigmented Discharge After subsequent mixing of components 1 to 5 and 7, stirring was continued for a further 10 hours until a final viscosity of 3,500 mPa·s was achieved.

Claims (15)

A formaldehyde-free aqueous composition for discharge printing of fabrics, the composition comprising:
at least one reducing agent,
at least one synthetic thickener,
at least one humectant,
at least one pH adjusting agent;
optionally at least one pigment, and optionally at least one binder,
A composition comprising. Composition according to claim 1, wherein the at least one synthetic thickener is a polyacrylic compound, preferably selected from acrylic acid copolymers, preferably comprising a dense oil and auxiliaries. 2. The at least one binder is based on a copolymer of two or more of poly(butyl acrylate), butyl(acrylate), ethyl(acrylate) and styrene, polyvinyl acrylate, acrylonitrile or mixtures thereof. or 2. The composition according to at least one item of 2. Composition according to at least one of claims 1 to 3, wherein the wetting agent is selected among urea, glycerin or mixtures thereof. Composition according to at least one of claims 1 to 4, wherein the reducing agent comprises or consists of a sulfinic acid derivative. At least one of claims 1 to 5, further comprising one or more components selected from the group consisting of crosslinkers, softeners, emulsifiers, antifoams, rheology modifiers and antioxidants or mixtures thereof. The composition described in Section. Composition according to at least one of claims 1 to 6, wherein the composition is free of any natural thickeners. 3-30% by weight of at least one reducing agent,
0.05% to 6% by weight of at least one synthetic thickener;
3-45% by weight of at least one wetting agent;
0.05 to 4% by weight of at least one pH adjuster;
0-30% by weight of at least one binder,
0-2% by weight of at least one emulsifier,
0 to 1% by weight of at least one antifoaming agent,
0-3% by weight of at least one crosslinker,
0-3% by weight of at least one softener;
0-2% by weight of at least one rheology modifier,
0-2% by weight of at least one antioxidant;
0 to 6% by weight of at least one pigment dispersion;
including;
the remainder up to 100% by weight is water;
where the weight percentages are based on the total weight of the composition;
Composition according to at least one of claims 1 to 7. A method for producing the composition according to at least one of claims 1 to 8, comprising the following step A and optionally steps B and C:
Step A: If at least one pigment is present in the composition according to at least one of claims 1 to 8, excluding said at least one pigment, the composition according to at least one of claims 1 to 8 is mixing and homogenizing all components for said composition;
Step B: adding to the mixture obtained in step A at least one dispersion comprising said at least one pigment;
Step C: Mixing and homogenizing the mixture obtained in Step B. Use of a formaldehyde-free aqueous composition according to at least one of claims 1 to 8, or produced according to the method according to claim 9, for a process for discharging fabrics, in particular for a white discharge printing or colored discharge printing process. Use of formaldehyde-free aqueous compositions. Step 1: Providing colored fabric;
Step 2: Printing step: printing said fabric with a formaldehyde-free aqueous composition according to at least one of claims 1 to 8, or a formaldehyde-free aqueous composition prepared according to claim 9. printing the fabric using a material;
Step 3: first drying step: drying the fabric obtained in step 2;
Step 4: Washing step: washing the fabric obtained in step 3, wherein the fabric is rinsed with a rinsing fluid and/or soaped with a soaping fluid;
Step 5: Second drying step: drying the fabric obtained in step 4;
A discharge printing method for printing textiles, including The washing step includes:
a first cold and/or hot rinsing step in which the printed fabric is rinsed with a rinsing fluid selected from cold water or aqueous H ₂ O ₂ solution; a high temperature soaping step, in which washing is performed with a soaping fluid selected from soapy water at a temperature of
a second low temperature rinsing step in which the printed fabric is rinsed with a second rinsing fluid selected from cold water;
12. The method of claim 11, comprising: said first drying step is carried out at a temperature of 140° C. to 180° C., preferably for 1 to 5 minutes, and/or
Said second drying step is carried out at a temperature of 120°C to 160°C, preferably for 8 to 20 minutes.
13. A method according to at least one of claims 11 or 12. A method according to at least one of claims 11 to 13, which does not include a curing step and/or a steam treatment step. Fabric treated with a composition according to at least one of claims 1 to 8 or a composition obtained according to claim 9 in a discharge printing method according to at least one of claims 11 to 14.

Images