FR3004198A1 - NEW PIGMENT STAINING PROCESS - Google Patents

Abstract

A process for the pigment dyeing of individualized textile fibers or the textile support obtained from said fibers comprising pretreating the fibers or the support with at least one polymer and then dyeing the fibers or the support thus pretreated with pigments, characterized in that the polymer is a (co) polymer based on vinylamine.

Description

The invention relates to the field of textiles. More specifically, the invention relates to a novel process for pigment dyeing textile materials by exhaustion.

There are 2 types of product to color textile materials: dyes and pigments. Dyes are water-soluble compounds. They can be of different classes, such as direct, reactive, sulfur, indigo, basic or acidic. The interest of the dye is that it will penetrate even within the fiber. However, the use of dyes requires additional rinsing steps, which generate highly polluted water residual dyes that can cause ecological problems. In addition, the staining process is long and requires large amounts of water and energy.

The pigments are chemically inert, are neither soluble in water nor in most commonly used solvents and have no affinity for fibers. As a result, they can not penetrate the fiber like the dye but remain only on the surface. Their use involves the use of binder in general thermoplastic elastomer type and fixers in order to obtain good color resistance to wet tests. In the textile industry pigments are surely the easiest and most used way to color textile materials because they have many advantages: - a versatile appearance (all fibers), - their ability to preserve the environment (few rejects, no subsequent washes), - good resistance to light, water and solvents, - a very wide choice of grades, - an inexpensive application process.

It is known to those skilled in the art that pigment dyeing by exhaustion is possible by providing a substantivity to the pigments by adding a cationic charge aid providing affinity to the pigments for the fiber. The textile supports are thus cationized prior to the actual dyeing step.

The person skilled in the art has at his disposal various cationization agents enabling him to improve the affinity of the fiber with the pigments.

US5006129 discloses a pigmentation method which comprises a step of pretreating the textile with a cationizing agent comprising a quaternary ammonium function.

US5252103 claims a pigmentation method using cationic compounds comprising a quaternary ammonium function. Among the compounds used, mention may be made of the acrylamide / 2- (methacryloyloxy) ethyl trimethylammonium chloride copolymer.

However, the prior art does not give complete satisfaction. The current problem is therefore to find a pigment dyeing process for dyeing textile supports based on cellulose or a mixture of cellulose and synthetic fibers with the following advantages: - complete exhaustion of the dyebaths, - very high colouristic yields, - a high affinity of the pigment for the fiber, - very short process times and low volumes of water required, - very high color fastness to wet tests, - very low COD and DB05 loads in the effluents.

The problem to be solved by the invention is to provide a novel process for pigment dyeing textile materials by exhaustion having the advantages mentioned above while overcoming the disadvantages of the prior art.

The Applicant has developed a new process for pigment dyeing individualized textile fibers or the textile support obtained from said fibers of pretreating the fibers or the support with at least one polymer and then dyeing the fibers or the support thus pre-treated with of pigments.

The process is characterized in that the polymer is a vinylamine (co) polymer. The invention applies more particularly to the pigment dyeing of natural and / or synthetic fibers. As natural fibers, mention may be made of natural cellulosic plant fibers, for example cotton, linen, regenerated celluloses such as viscose, modal or modified cellulose such as acetate or triacetate. There may also be mentioned animal fibers such as wool and silk. Examples of synthetic fibers are acrylic, modacrylic, polyester, polyamide-based fibers and mixtures thereof. The support obtained from the fibers may be a woven or non-woven or knitted support. . (Co) Polymers of VinylAmines (PVA) The PVA used in the new process may be derived from various processes known to those skilled in the art. We can mention the PVA resulting from the hydrolysis of the homopolymers or copolymers of N vinylformamide, or the PVA resulting from the Hofmann degradation. PVA resulting from the total or partial hydrolysis of an N-vinylformamide (co) polymer In a first step, a (co) polymer of N-vinylformamide (NVF) must be obtained, the NVF having the following pattern: CHF-CH-NH-CH 8 Subsequently, this NVF motif must be converted by hydrolysis to VinylAmin: -CH- CH-2 NH2 Hydrolysis can be carried out by acid action (acid hydrolysis) or base (basic hydrolysis).

Depending on the amount of acid or base added, the NVF polymer or copolymer will be partially or completely converted to VinylAmine. - Hofmann degradation PVA Hofmann degradation is a reaction that Hofmann discovered in the late nineteenth century to convert an amide (or even an acrylonitrile) into a primary amine by removing carbon dioxide. The reaction mechanism is detailed below. In the presence of a base (soda), a proton is torn from the amide. The amidate ion formed then reacts with the active chlorine (C12) of the hypochlorite (eg: NaC1O which is in equilibrium: 2 NaOH + C12 <1> NaClO +). NaCl + H2O) to give Nchloramide. The base (NaOH) removes a proton from chloramide to form an anion. The anion loses a chloride ion to form a nitrene which is transposed to isocyanate.

R-FI = C = 1: 5 By reaction between the hydroxide ion and the isocyanate, a carbamate is formed. R-171 = C = b + OH R-NH -CO2- After decarboxylation (removal of CO2) from the carbamate, a primary amine is obtained.

R-NH2-OO2- -002 R-NH2 H + For the conversion of all or part of the amide functions of an acrylamide (co) polymer amine function, 2 main factors occur (expressed in molar ratios). These are: - Alpha = (alkaline and / or alkaline earth / acrylamide hypohalide) and - Beta = (alkali and / or alkaline earth hydroxide / alkaline and / or alkaline earth hypohalide). According to some embodiments, the PVA-based (co) polymer may comprise other ionic and nonionic monomers. The nonionic monomer (s) that may be used in the context of the invention may be chosen, in particular, from group comprising vinyl monomers soluble in water. Preferred monomers belonging to this class are, for example, acrylamide, N-isopropylacrylamide, N, N-dimethylacrylamide. Also, N-vinylformamide, and N-vinylpyrrolidone, can be used. A preferred nonionic monomer is acrylamide. The cationic monomer or monomers that can be used in the context of the invention may be chosen, in particular from acrylamide, acrylic, vinylic, allylic or maleic monomers having a quaternary ammonium function. Mention may be made, in particular and in a nonlimiting manner, of quaternized dimethylaminoethyl acrylate (ADAME) and dimethylaminoethyl methacrylate (MADAME), dimethyldiallylammonium chloride (DADMAC), acrylamidopropyltrimethylammonium chloride (APTAC) and methacrylamido propyltrimethylammonium chloride (MAPTAC). The anionic monomer (s) that can be used in the context of the invention can be chosen from a large group. These monomers may have acrylic, vinyl, maleic, fumaric, allylic functional groups and contain a carboxylate, phosphonate, phosphate, sulphate, sulphonate or other anionically charged group. The monomer may be acidic or in the form of salt or alkaline earth metal or corresponding alkali metal of such a monomer. Examples of suitable monomers include acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic acid, fumaric acid and strong acid monomers having, for example, an acidic function. sulfonic or phosphonic acid such as 2-acrylamido-2-methylpropanesulphonic acid, vinylsulfonic acid, vinylphosphonic acid, allylsulfonic acid, allylphosphonic acid, styrene sulfonic acid and their water-soluble salts an alkali metal, an alkaline earth metal, and ammonium.

According to a preferred embodiment the (co) polymer based on PVA is derived from the Hofmann degradation performed on a (co) polymer base comprising acrylamide or derivatives. According to another embodiment of the invention, it is possible to use Hofmann degradation (co) polymers carried out on a (co) polymer base comprising acrylamide or derivatives and at least one polyfunctional compound containing at least one minus 3 heteroatoms each having at least one mobile hydrogen.

Preferably, the polyfunctional compound is selected from the group comprising polyethyleneimine, polyamine, polyallylamine. In general, the polymers of the invention do not require development of a particular polymerization process. Indeed, they can be obtained according to all polymerization techniques well known to those skilled in the art. It may especially be solution polymerization; gel polymerization; precipitation polymerization; emulsion polymerization (aqueous or inverse); suspension polymerization; or micellar polymerization.

Pretreatment: According to the invention, the textile material undergoes a pretreatment step first. This step involves contacting the textile material with at least one vinylamine (PVA) based (co) polymer in a bath comprising water. The PVA (co) polymer is used at dosages ranging from 1 to 10% by weight of material to be dyed, preferably from 3 to 8%. The polymer / pigment ratio by weight is between 1:10 and 10: 1, preferably between 3: 1 and 7: 5, more preferably the ratio is 5: 3. The pretreatment is generally carried out at a temperature of between 20 and 100 ° C, preferably between 30 and 80 ° C. The pretreatment time is between 1 and 60 minutes, preferably between 5 and 40 minutes. The bath ratio is the weight ratio between the total dry matter and the total bath constitutive solution. Thus, for example a bath ratio of 1:10 means 10 liters of water per 1 kg of textile material. According to the invention the bath ratio for pretreatment is between 1: 5 and 1:40, preferably between 1:10 and 1:30. The pretreatment step is carried out at a pH of between 3 and 8, preferably the pH is maintained between 5 and 7. The pH is maintained by adding an acid or an acid pH buffer. For example, acetic acid, formic acid, ammonium sulfate and sodium carbonate may be mentioned. After pretreatment the bath is emptied. The textile material is rinsed at least once with water having a temperature between 10 and 30 ° C.

Other compounds may be introduced during the pretreatment step. By way of example, mention may be made of antifoam agents and anti-wear agents. The pretreatment can be carried out with the means known to those skilled in the art.

Preferably, the pretreatment may be carried out in a dyeing apparatus such as jet flow, over flow, boat, jigger, autoclave, industrial drum, dye wire coil or skeins. In order to facilitate pretreatment, the textile material may optionally undergo at least one prior step known to those skilled in the art. By way of example, mention may be made of the steps of degreasing, desizing or bleaching. The pretreatment step may be followed by a softening step, stoning or even biopolishing of the textile material before the dyeing step.

Dyeing: According to the invention after the pretreatment step the material undergoes a dyeing step. This step involves contacting the pretreated textile material with at least one pigment in a bath comprising water. More specifically, the textile material is colored using the technique of pigmentation by exhaustion. This technique involves depleting the bath of pigments by transfer of the latter to the textile material. The pigment (s) may be introduced into the bath in powder form or in liquid form. Preferably, the pigments are introduced in liquid form. In the case of the liquid form, the pigment or pigments are dispersed in at least one solvent. The concentration of pigment in the solvent is between 10 and 50%, preferably between 25 and 35%. Preferably the solvent is water. In general, the pigment or pigments are added to the bath at a level of from 0.1% to 10% by weight of material to be dyed. The dyeing is carried out at a temperature between 20 and 90 ° C, preferably between 40 and 80 ° C. The rise in temperature is less than 10 ° C per minute, preferably it is between 1 and 4 ° C per minute.

Once the target temperature is reached, the latter is maintained for 1 to 60 minutes, preferably between 5 and 40 minutes. The bath ratio for dyeing is between 1: 5 and 1:40, preferably between 1:10 and 1:30.

After dyeing, the bath is emptied. The textile material is rinsed at least once with water. Preferably the water has a temperature between 10 and 30 ° C. Other compounds may be present during the dyeing step. By way of example, mention may be made of defoamers or anti-stressing agents. Post treatment In order to improve the fastness of the textile material to wet tests, a post-treatment can optionally be implemented. This post-treatment consists of the addition of at least one binder and / or at least one fixing agent. The binder is a composition comprising low molecular weight prepolymers. During the dewatering and drying (high temperature) steps, these prepolymers will react to form a film that traps and integrates the pigments into the fiber. The binder is used at dosages of between 0.1 and 15%, preferably between 1 and 10% by weight of material. The crosslinking of the binder is carried out at a temperature of between 50 and 250.degree. C., preferably between 100 and 200.degree. Exposure to high temperature lasts between 1 and 20 minutes, preferably between 3 and 10 minutes. The binder may be based on acrylate, styrene acrylate, styrene butadiene and vinyl acrylate. The fixing agent reacts to form a three-dimensional network around the fiber at the time of drying. The fixing agent is used at dosages of between 0.1 and 15%, preferably between 1 and 10% by weight of material. The fixing agent is used at a temperature of between 10 and 90 ° C, preferably between 20 and 60 ° C. The pH of the bath is maintained between 3 and 6 by adding an acid or an acid pH buffer.

Once the fixing agent introduces the bath is heated. The rise in temperature is less than 10 ° C per minute, preferably it is between 1 and 4 ° C per minute. Once the target temperature is reached, the latter is maintained for 1 to 60 minutes, preferably between 5 and 30 minutes.

The bath ratio is between 1: 5 and 1:40, preferably between 1:10 and 1:30. The fixing agent may be based on polyisocyanate, melamine formaldehyde, dimethyl dihydroxyethylene urea (DMDHEU).

After the post treatment the bath is emptied. The textile material is rinsed at least once with water having a temperature between 10 and 30 ° C. The post-treatment stage may be followed by a softening, staking or even biopolishing step of the textile material.

One of the advantages of the invention lies in the high exhaustion rate of the pigments present in the dyebath, the baths discharged into the effluents thus being very slightly charged.

Surprisingly, it has been found that PVA allows much higher pigment depletion than conventional cationic products. In fact, we obtain exhaustion rates greater than 95% for light and medium colors, and greater than 90% for dark colors.

Moreover, without wishing to emit any theory, it would seem that the strong pigment / fiber bond obtained avoids a systematic use of binder and / or fixer. During subsequent softening it was also found a very good resistance of the pigment, no or little disgorgement.

The following examples illustrate the invention without limiting it.

EXAMPLES I / PREPARATION OF THE POLYMER Polymer A is obtained by a Hofmann degradation reaction on a base copolymer (20% of active material) of acrylamide (70 mol%) and of dimethyldiallyl ammonium chloride (DADMAC) (30%). molar) branched (MBA: 1000 ppm / active ingredient) modified with a polyethyleneimine polymer (BASF type Polymin HM), at 1% active ingredient. To do this, the polyethyleneimine is mixed with the DADMAC monomer and the MBA in the reactor. The acrylamide will be incorporated in continuous casting for 2 hours, in a reaction medium maintained at 85 ° C. Catalysis will be SPS and MBS, catalysts well known to those skilled in the art. The precursor polymer thus obtained has a viscosity of 5500 cps (LV3, 12 rpm). The Hofmann degradation itself proceeds in the same manner as in Example 1 of Applicant's patent PCT / FR / 2009/050456. The acrylamide-derived copolymer A thus produced has an intrinsic viscosity of 0.72 (25 ° C, Brookfield LV1, 60 rpm) and a concentration of 8%.

II / IMPLEMENTATION OF THE PROCESS Example 1 A 150/50 cotton / viscose 50/50 knit knit of 150 g / m 2 was degreased in a turnstile boat. The bath ratio is 1:25. To the bath 1 g / l of a detergent wetting agent is added. The bath is then heated and kept at 60 ° C for 25 minutes. The bath is then emptied and the material is then rinsed twice cold with water at 15 ° C. The pretreatment is then carried out with a bath ratio of 1:25. The pH is adjusted to 9 with sodium carbonate and 5% by weight of polymer A material is added. The bath is heated and maintained at 60 ° C for 30 minutes. The bath is emptied and the material is then rinsed twice cold with water at 15 ° C. The dyeing is then carried out in a bath ratio of 1:25. In the bath, which has an initial temperature of 15 ° C is added 3% blue pigment 15/3. Then heated to 60 ° C at 3 ° C per minute. The temperature is maintained for 30 minutes. The bath is emptied and the material is then rinsed twice cold with water at 15 ° C.The treated material is softened with a softener of nano silicone emulsion type dosed at 2% for 15 minutes, bath temperature at 40 ° C. ° C, pH 5 adjusted with acetic acid.

Example 2 Pants of 100% twill cotton material 205g / m2 3/1 are first desilbed in an industrial drum machine. The bath ratio is 1:10. The pH is adjusted to 6 with acetic acid. In the bath is added 3 g / 1 of an amylase. The desizing takes place at 60 ° C for 20 minutes. The material is then rinsed twice cold with water at 15 ° C. The pants are then cationized in a 1:10 bath ratio at pH 6 adjusted with acetic acid. 5% by weight of polymer material is added to the bath. The bath is heated and maintained at 60 ° C for 30 minutes. The material is then rinsed twice cold with water at 15 ° C. The dyeing is then carried out in a bath ratio of 1:10. In the bath, which has an initial temperature of 15 ° C is added 3.5% green pigment 7. Then heated to 60 ° C at 3 ° C per minute. The temperature is maintained for 40 minutes. The bath is then emptied and the material is then rinsed twice with water at 15 ° C. The material is then staged for 20 minutes in a 1:10 bath ratio at pH 4.5 with 1.5% acid cellulase. The bath is then emptied and the material is then rinsed twice cold with water at 15 ° C. The material is then softened with 1% silicone microemulsion and 1% fatty acid for 15 minutes, bath temperature at 40 ° C., pH 6 adjusted with acetic acid, the material is then dewatered and dried.

Example 3 A 100% cotton poplin fabric 105g / m2 pre-glued is first bleached on over flow dyeing machine with a 1:20 bath ratio. The following products are added to the whitening bath: antifoam, anti-acid, hydrogen peroxide stabilizer, hydrogen peroxide, caustic soda. The bath is then heated to 98 ° C for 30 minutes, the bath is cooled to 70 ° C and the material neutralized to pH 7 with acetic acid. The bath is then emptied and the material is then rinsed once cold. The cationization is then carried out in a bath ratio of 1:20 to pH 5.5 adjusted with acidic pH buffer.

5% by weight of PVA cationizing agent material, an anticaking agent and an antifoaming agent are added to the bath. The bath is heated and maintained at 60 ° C for 30 minutes. The material is then rinsed twice with water at 15 ° C. The dyeing is then carried out in a bath ratio of 1:20 to pH 5.5. 2% of orange pigment 34, 1% of yellow pigment 83, an antifoaming agent, an anticaking agent and a bath dispersant which has a temperature of 15 ° C. are added. Then heated to 70 ° C at 1 ° C per minute. The temperature is maintained for 20 minutes. At 70 ° C an acrylic binder is added to the bath and dosed at 5%. The bath is then emptied and the material is then rinsed once cold. The material is then softened with a hydrophilic silicone emulsion softener dosed at 2% for 20 minutes, bath temperature at 40 ° C., pH adjusted with an acid buffer. Example 4 The cotton fabric of Example 3 is continuously bleached, coiled and dried. The fabric is then padded on a priming scarf in a bath containing 75 g / l of polymer A, at pH 6. The carrier level is maintained at 60-80%, the material is then dried on a dry tenter train. 100-120 ° C. The fabric thus treated is then dyed according to the same protocol described in Example 3. Example 5 - Counterexample Example 3 is reproduced identically by replacing the polymer A with PRECAT 3005 (chloromethylated MADAME homopolymer) distributed by CHT, R BEITLICH GMBH used at 3%. The bath exhaustion, color and friction fastness checks are carried out. III / EVALUATION TESTS: Evaluation of the exhaustion rate: At the end of each dyeing, a bath sample is taken in order to control the exhaustion rate E (%) of the dye bath pigments with the aid of a visible UV spectrophotometer (spectral range 190 to 900 nm, quartz cell 10 mm). The latter is calibrated with successive dilutions of the initial colored pigment solution. E (%) = Cl - Cf / Cl * 100. Evaluation of Dry and Wet Condolidities: A final tissue sample is taken to check the dry and wet rubbing fastnesses according to standard NF EN ISO 105-X12 (2003) and using a crockmeter. The color stains on the cotton controls are evaluated using the gray scale and the ISO 105 - A03 (2005) standard. Staining Evaluation: The final tissue color is compared against the standard using a spectrocolorimeter under the D65 illuminant and at a 10 degree angle. The color differences are determined by calculation of the Delta E (CIE 2000) and the color forces (%) compared to the counterexample.

Results Test Frictional Strength E (%) FC (%) Wet Dry Example 1 4-5 4 93.5 108.6 Example 2 4 3-4 91.2 112.4 Example 3 4-5 4 92.8 110, Example 4 4-5 4 90.8 109.8 Example 5 3-4 3 86.4 100 It is observed that the new cationization pretreatment makes it possible to obtain, with respect to a conventional process: 1 to 2 points in result on dry and wet friction fastnesses, - an increase in the depletion rate E (%) of the pigments from 5 to 10%, - an increase in the CF (%) pitch of 5 to 15%.

Claims (3)

CLAIMS1 / A process for the pigment dyeing of individualized textile fibers or of the textile support obtained from said fibers of pretreating the fibers or the support with at least one polymer and then dyeing the fibers or the support thus pretreated with pigments, characterized in that that the polymer is a vinylamine (co) polymer. 2 / A method according to claim 1, characterized in that the (co) polymer based on vinylamine is derived from the total or partial hydrolysis of a (co) polymer N10 vinylformamide. 3 / A method according to claim 1, characterized in that the (co) polymer based on vinylamine is derived from a Hofmann degradation reaction carried out on a (co) polymer base comprising acrylamide or derivatives. 4 / A method according to claim 3, characterized in that the (co) polymer base additionally contains at least one polyfunctional compound containing at least 3 heteroatoms each having at least one mobile hydrogen. 5 / A method according to claim 4, characterized in that the polyfunctional compound is selected from the group comprising polyethyleneimine, polyamine, polyallylamine. 6 / A method according to claim 1, characterized in that the (co) polymer is 1 to 10% by weight of the material to be dyed, preferably 3 to 8%. 7 / A method according to claim 1, characterized in that the polymer / pigment ratio by weight is between 1:10 and 10: 1, preferably between 3: 1 and 7: 5, more preferably equal to 5: 3. 8. The process as claimed in claim 1, characterized in that the pigments represent from 0.1% to 10% by weight of material to be dyed. 9 / A method according to claim 1, characterized in that the weight ratio between the total dry matter and the total solution is between 1: 5 and 1:40, preferably between 1:10 and 1:30.