EP0645429B1 - Water-in-oil thickening dispersions, process for their preparation and their use in textile printing - Google Patents

Description

This request concerns water dispersions in thickening oil, their preparation process and their application in textile printing.

In the textile industry, printed fabrics are currently experiencing significant development. They are generally obtained by printing techniques using especially printing pastes containing either pigments, i.e. reactive dyes with well-defined rheological properties according to the article desired and the type of dye used. These properties rheological are obtained by the use of thickening agents. If in pigment printing, it has been known since a few years of using polymeric thickeners synthetics based on acrylic acid (patent applications European N ° 161 038, 169 674, 186 361, 197 635, 325 065 and 343 840) more delicate reactive dye printing implement, carried out in very alkaline media in presence of a high concentration of electrolyte, requires the use of specific thickeners from products natural such as sodium alginate or guar gums with all the disadvantages inherent in this type of product natural: price fluctuation, supply difficulties, variations in qualities.

Research Disclosure vol. 307 N ° 26, November 1989 described on page 789, a mixture of a homopolymer and / or a copolymer of acrylic acid or acrylamide plus an ether or a cellulose ester of molecular weight between 1.10 ⁴ and 1.10 ⁶ , devoid of thixotropic properties and of a fluidity adapted to have a regular impression.

EP-A-186 361 describes the use of a polymer water-soluble in water-in-oil emulsion as thickener for high viscosity textile printing paste, even in presence of large amounts of electrolytes.

In order to overcome these drawbacks, the plaintiff discovered thickening compositions which can be used in printing textiles with dyes reactive, stable, water-miscible and leading to good quality prints with good color rendering, a pleasant touch and a very satisfying unison.

The compositions according to the invention are water-in-oil dispersions, stable, self-reversing, miscible with water, consisting of an oil phase, a phase aqueous and at least two emulsifiers including at least one is of the water in oil type, and at least one is of the oil type in water, characterized by the fact that they contain 20 to 50% by weight of a mixture consisting of a polymer anionic, water-soluble, belonging to the group of carboxymethylcelluloses, designated C, and by an anionic polymer synthetic, crosslinked, insoluble in water but swellable to water, designated P, based on acrylic acid, designated AA, partially salified with an alkali metal, designated M, optionally copolymerized with 2-acrylamido-2-methyl alkali metal propanesulfonate M, designated AMPSM, crosslinked with a diethylenic carboxylic acid and in which the molar ratio of salified acid functions over the whole free or salified acid functions is between about 0.6 and about 0.9, the C / P + C weight ratio being between 0.01 and 0.5.

The expression “alkali metal M” designates sodium or potassium. Thereafter, acrylic acid is designated AA, its alkali metal salt AAM, its sodium salt AANa, and its potassium salt AAK, 2-methyl-2-acrylamido acid propanesulfonic is designated AMPS, its alkali metal salt AMPSM, its sodium salt AMPSNa and its potassium salt AMPSK.

The expression "diethylenic carboxylic acid" denotes a crosslinking monomer, designated R, polymerizable with acrylic acid and having a carboxyl function and two ethylenic functions such as bisacrylamidoacetic acid, designated ABAA, diallyloxyacetic acid, designated DALLA.

By "water in oil type emulsifying agent", emulsifying agents are designated having an HLB value (hydrophilic-lipophilic balance, Kirk-Othmer, Encyclopedia of Chemical Technology, 3rd edition, volume 8, page 910) low enough to provide water-in-oil emulsions such as sorbitan esters such as sesquioleates sorbitan, the sorbitan monooleate.

By "oil-in-water type emulsifying agent", emulsifying agents are designated having an HLB value high enough to provide oil-in-water emulsions such as ethoxylated nonylphenols, sorbitan esters ethoxylated like sorbitan hexaoleate ethoxylated with 50 moles of ethylene oxide.

By "crosslinked polymer" is meant a polymer nonlinear in the state of a three-way network dimensions insoluble in water but swellable with water.

The expression "group of carboxymethylcellulose" designates the products resulting from the reaction of Williamson with sodium chloroacetate on an alkali-cellulose (cf. Ullmann's Encyclopedia of Industrial Chemistry, 5th edition, volume A5, pages 477-488) such as products marketed by the plaintiff under the designation of TYLOSE® C. These products have a viscosity range of 100 to 4000 mPa.s. determined with a drop viscometer ball, HÖPPLER, at a temperature of 20 ° C, in a 2% solution by weight in water. TYLOSE® C 1000 therefore designates a sodium carboxymethylcellulose exhibiting under the conditions defined above an average viscosity of 1000 mPa.s. Preferably, a carboxymethylcellulose is used with the state of fine powder.

A more particular subject of the invention is the compositions as defined above characterized by the fact that they contain from 20 to 50% by weight of a mixture of anionic polymers consisting of 10 to 50% by weight of a carboxymethylcellulose, C, and by 90 to 50% by weight of a crosslinked polymer, P, AA-AAM-AMPSM containing molar proportions from 0 to 30% of AMPSM and from 100 to 70% a mixture of AA and AAM containing in molar proportions of 20 to 40% AA and 80 to 60% AA, cross-linked with 0.01 at 0.06% in molar proportions relative to the monomers used, of a chosen diethylenic carboxylic acid in the group made up of ABAA and DALLA.

Among these latter compositions, the invention has in particular the compositions as defined above in which the polymer P is crosslinked by ABAA.

• AA-AAM-AMPSM, contenant en proportions molaires de 10 à 30 % d'AMPSM et de 90 à 70 % d'acide acrylique dont 60 à 80 % sont sous la forme d'un acrylate de métal alcalin.
• AA-AAM, contenant en proportions molaires de 30 à 40 % en poids d'AA et de 70 à 60 % d'AAM.

Among these latter compositions, there may be mentioned more particularly the compositions as defined above in which the polymer P is chosen from the following crosslinked polymers:

• AA-AAM-AMPSM, containing in molar proportions from 10 to 30% of AMPSM and from 90 to 70% of acrylic acid of which 60 to 80% are in the form of an alkali metal acrylate.
• AA-AAM, containing in molar proportions 30 to 40% by weight of AA and 70 to 60% of AAM.

Preferably, the compositions of the invention contain 10 to 20% by weight of a carboxymethylcellulose sodium and from 20 to 30% by weight of a polymer P, as defined above.

The compositions according to the invention contain generally 2 to 10% by weight of a mixture of agents emulsifiers, and advantageously from 3 to 8% by weight per relative to the total weight of the composition, of which 40 to 60% are consisting of one or more emulsifiers of the water type in oil and 60 to 40% are constituted by a several oil-in-water type emulsifiers.

The oil phase of the compositions represents 15 to 35% by weight, and advantageously from 20 to 25% by weight per relative to the total weight of the composition. This oil phase preferably consists of a commercial mineral oil containing saturated hydrocarbons of the paraffinic, isoparaffinic type, naphthenic or cycloparaffinic, having a density at 15 ° C from about 0.7 to about 0.9 and a boiling point higher than 180 ° C, such as white oils sold by the company SHELL or ISOPAR®, marketed by the EXXON company.

The compositions according to the invention contain 25 to 60% water in which the polymer blend is partially soluble. The compositions according to the invention may also contain various additives such as chelating agents, transfer agents. Advantageously, the compositions according to the invention contain from 0.01 to 0.10% by weight of a chelating agent, and advantageously 0.02 to 0.5% by weight relative to the total weight of the composition of sodium diethylenetriaminepentaacetate, designated DTPANa.

The invention also relates to a method of preparation of the compositions defined above.

According to the invention, the compositions defined above can be prepared by a process characterized by what we do a radical polymerization reaction as a water-in-oil emulsion, from a solution aqueous containing the monomers constituting the polymer P, and possibly a chelating agent, which is emulsified in an oil phase in the presence of one or more agents water-in-oil type emulsifiers, the polymerization reaction being initiated by the introduction into the emulsion of departure of a product generating free radicals such as azo derivatives such as azobisisobutyronitrile, designated AIBN, or a Redox couple such as the hydroperoxide couple cumene - sodium disulfite, then when the reaction of polymerization is complete, which is introduced into the dispersion obtained, at a temperature below 30 ° C, a or more oil-in-water type emulsifiers and the desired amount of anionic polymer C.

Conventionally, the polymerization reaction is carried out with stirring, in an inert atmosphere, at from a perfectly deoxygenated reaction medium.

• la polymérisation est amorcée par un couple Redox, à une température inférieure ou égale à 10°C, puis elle est conduite de manière quasi adiabatique jusqu'à une température supérieure ou égale à 60°C,
• le couple Redox utilisé est le couple hydroperoxyde de cumène - disulfite de sodium, à la dose de 10 à 100 ppm molaire par rapport aux monomères d'hydroperoxyde de cumène et de 20 à 100 ppm molaire par rapport aux monomères de disulfite de sodium.

Under preferential conditions for implementing the invention, the process described above is carried out as follows:

• the polymerization is initiated by a Redox couple, at a temperature less than or equal to 10 ° C., then it is carried out in an almost adiabatic manner up to a temperature greater than or equal to 60 ° C.,
• the Redox couple used is the cumene hydroperoxide - sodium disulfite couple, at a dose of 10 to 100 ppm molar with respect to the cumene hydroperoxide monomers and from 20 to 100 ppm molar with respect to the sodium disulfite monomers.

The compositions according to the invention have interesting rheological properties which are highlighted evidence by determining, with a BOHLIN type rheometer VOR, the complex module, G *, the conservation module (storage modulus) G ', the loss angle, δ, of aqueous media containing them.

These interesting properties justify their application in the textile industry for the preparation of printing pastes containing reactive dyes. In the following tables the various characteristics are mentioned rheological properties of printed fabrics with printing pastes obtained from the compositions according to the invention. These printing pastes are obtained by mixing 40 g of RB 25 REMAZOL® red marketed by the applicant, 10 g of sodium hydrogencarbonate, 50 g of urea, the necessary amount of a dispersion according to the invention to provide 10.6 g of polymer blend anionic and the necessary amount of water to obtain 500 g printing paste (printing paste contains consequence 2.12% by weight of mixture of anionic polymers). The reference printing paste is prepared in mixing 40 g of RB 25 REMAZOL® red, 10 g of hydrogen carbonate sodium, 50 g urea, 15 g sodium alginate and the necessary amount of water to obtain 500 g of dough printing.

(i) Flow oscillation (précisaillement à 1 000 s^-1 pendant 5 minutes, suivi d'une analyse dynamique pendant 0,5 s à 20 Hz) conditionnement de la pâte suivie d'une reprise de structure instantanée,

(ii) oscillation (analyse dynamique à 1Hz pendant 1 000 s), reprise de structure jusqu'à l'équilibre,

(iii) strain sweep test (analyse dynamique à 1Hz par balayage en déformation), détermination du domaine linéaire de viscoélasticité.

With printing pastes, we print 100% cotton fabrics, then we determine visually on the printed fabrics, the touch, designated To, the unison, designated Un, and the color yield, designated Re. We also determine the characteristics rheological of these pastes with a BOHLIN VOR rheometer at room temperature, on a 7.5 g test portion, with a coaxial cylinder C 25HS, under the following conditions:

(i) Flow oscillation (precision at 1000 s ^-1 for 5 minutes, followed by a dynamic analysis for 0.5 s at 20 Hz) conditioning of the dough followed by an instantaneous resumption of structure,

(ii) oscillation (dynamic analysis at 1Hz for 1000 s), resumption of structure until equilibrium,

(iii) strain sweep test (dynamic analysis at 1Hz by strain sweep), determination of the linear range of viscoelasticity.

The following examples illustrate the invention without however limit it.

EXAMPLE 1

• 146 g (2,026 moles) d'acide acrylique,
• 74,2 g (0,358 mole) d'acide acrylamido-2 méthyl-2 propanesulfonique,
• 286,9 g d'une solution aqueuse contenant 96,6 g (1,776 mole) d'hydroxyde de potassium,
• 0,9 g d'une solution aqueuse contenant 0,36 g (0,751 mmole) de diéthylènetriaminepentaacétate de sodium,
• 0,142 g (0,715 mmole) d'acide bisacrylamidoacétique et
• 191,8 g d'eau.

An aqueous solution is prepared containing:

• 146 g (2.026 moles) of acrylic acid,
• 74.2 g (0.358 mol) 2-acrylamido-2-methylpropanesulfonic acid,
• 286.9 g of an aqueous solution containing 96.6 g (1.776 mole) of potassium hydroxide,
• 0.9 g of an aqueous solution containing 0.36 g (0.751 mmol) of sodium diethylenetriaminepentaacetate,
• 0.142 g (0.715 mmol) of bisacrylamidoacetic acid and
• 191.8 g of water.

This aqueous solution is homogenized in a oil phase containing 250 g of SHELL S 8515 oil and 25 g of sorbitan sesquioleate for 20 minutes with a mixer SILVERSON so as to obtain a water-in-oil emulsion with a Brookfield viscosity of 3,500 mPa.s. determined at 10 ° C (axis 2, speed 20 rpm, LVT model).

The emulsion thus obtained is transferred to a polymerizer, then it is oxygenated by bubbling nitrogen and its temperature is adjusted to about 8 ° C. The polymerization is initiated with stirring by the introduction in 2 minutes 0.009 g (0.0473 mmol) of hydroperoxide 80% cumene (20 ppm molar compared to the monomers) dissolved in 8 g of oil S 8515, then after 4 minutes, by introduction in 40 minutes of 0.0136 g (0.0715 mmol) of sodium disulfite dissolved in 20 g of water, i.e. 30 ppm molar with respect to the monomers. Polymerization starts at the temperature of the reaction medium rises to 55 ° C., temperature which is then maintained for 1 hour.

The reaction medium is then gradually cooled. At 30 ° C., 20 g of ethoxylated nonylphenol with 10 moles of ethylene oxide are introduced (at this stage, the dispersion obtained is designated D ₂₁ ), then at 20 ° C., 117.6 g of carboxymethylcellulose are introduced ( TYLOSE® C 1 000 - HOECHST). 1140.6 g of a stable, self-reversible, water-miscible, water-in-oil dispersion containing 37.9% water, 22.6% oil, 3.95% surfactants and 35.6% of a mixture of anionic polymers containing by weight 29% of carboxymethylcellulose and 71% of an AA-AAK-AMPSK copolymer, 25.5 - 59.5 - 15 in molar proportions, crosslinked with 300 ppm molar of ABAA. This dispersion is designated D ₁ and its rheological and applicative characteristics are mentioned in the following tables.

EXAMPLE 2

An aqueous solution containing 220 g is prepared (3.053 mole) of acrylic acid, 0.9 g of an aqueous solution containing 0.36 g (0.715 mmol) of diethylenetriaminepentaacetate sodium, 0.109 g (0.55 mmol) bisacrylamidoacetic acid, 85.5 g (2.137 mole) sodium hydroxide and 393.5 g of water.

This aqueous solution is homogenized in an oil phase containing 250 g of SHELL S 8515 oil and 25 g of sorbitan sesquioleate as in Example 1, then the emulsion obtained is polymerized as in Example 1, using one part 0.0348 g (0.183 mmol) of 80% cumene hydroperoxide dissolved in 8 g of oil S 8515, i.e. 60 molar ppm relative to the monomers and 0.029 g (0.153 mmol) of sodium disulfite dissolved in 20 g of water, ie 50 molar ppm relative to the monomers. At the end of the polymerization reaction, 20 g of ethoxylated nonylphenol with 10 moles of ethylene oxide are introduced into the reaction medium, cooled to 30 ° C. A dispersion designated D _{22 is} thus obtained in which 117.6 g of carboxymethylcellulose (TYLOSE® C 1000 - HOECHST) are introduced at room temperature, with stirring as in Example 1. This gives 1140.6 g a stable, self-reversible, water-miscible, water-in-oil dispersion containing 22.62% oil, 3.94% surfactants, 39.7% water and 33.73% of a mixture of anionic polymers containing by weight 30.57% of carboxymethylcellulose and 69.43% of an AA-AANa copolymer, 30 - 70 in molar proportions, crosslinked with 180 molar ppm of ABAA. This dispersion is designated D ₂ and its rheological and applicative characteristics are mentioned in the following tables. In another test, TYLOSE® C 1000 is replaced by TYLOSE® C 300, the dispersion designated D ₃₂ is obtained.

EXAMPLE 3

An aqueous solution is prepared containing 165.25 g (2.2932 moles) of acrylic acid, 52.79 g (0.2547 moles) of 2-acrylamido-2-methylpropanesulfonic acid, 104.25 (1.858 moles) d potassium hydroxide, 0.9 g of an aqueous solution containing 0.36 g (0.751 mmol) of sodium diethylenetriaminepentaacetate, 0.151 g (0.7619 mmol) of bisacrylamidoacetic acid and 386.7 g of water. This aqueous phase with a total weight of 710 g is homogenized in an oil phase consisting of 240 g of ISOPAR® M oil (d = 0.79, Eb = 206-250 ° C) and 24 g of sorbitan sesquioleate as in Example 1, then the emulsion obtained is polymerized as in Example 1, using on the one hand, 0.01 g (0.0525 mmol) of 80% cumene hydroperoxide dissolved in 8 g d ISOPAR® M oil, 20 ppm molar with respect to the monomers, and 0.0145 g (0.0763 mmol) of sodium disulfite dissolved in 20 g of water, or 30 ppm molar with respect to the monomers. At the end of the polymerization reaction, 20 g of ethoxylated nonylphenol with 10 moles of ethylene oxide are introduced into the reaction medium, cooled to 30 ° C. A dispersion designated D _{23 is} thus obtained, into which 117.5 g of TYLOSE® C 1000 are introduced at ambient temperature, with stirring. 1139.5 g of a stable, self-reversible dispersion miscible with water, water in oil, containing 21.76% by weight of oil, 3.86% of surfactants, 38.72% of water and 35.66% of a mixture of anionic polymers containing 28.9% by weight of carboxymethylcellulose and 71.1% of a polymer AA-AAK-AMPSK, 27 - 63 - 10 in molar proportions, crosslinked with 300 ppm molar with respect to the ABAA monomers. This dispersion is designated D ₃ and its rheological and applicative characteristics are mentioned in the following tables. In another test, TYLOSE® C 1000 is replaced by TYLOSE® C 300, a dispersion designated D ₃₃ is thus obtained.

EXAMPLE 4

Example 2 is reproduced, starting from an aqueous solution containing 220 g (3.053 mole) of acrylic acid, 0.9 g of an aqueous solution containing 0.36 g (0.715 mole) of sodium diethylenetriaminepentaacetate, 0.109 g (0.550 mmol) bisacrylamidoacetic acid, 73.27 g (1.832 mole) sodium hydroxide and 405.7 g water. 1140.6 g of a stable, self-reversible dispersion, miscible with water, water in oil, containing 22.62% of oil, 3.94% of surfactants, 40.31% of water are thus obtained. and 33.13% of a mixture of anionic polymers containing by weight 31.12% of carboxymethylcellulose and 68.88% of a copolymer AA-AANa, 40 - 60 in molar proportions, crosslinked with 240 ppm molar with respect to the monomers d 'ABAA. This dispersion is designated D ₄ ; the intermediate dispersion obtained before the introduction of the carboxymethylcellulose is designated D ₂₄ . The rheological and application characteristics of these dispersions are mentioned in the following tables.

EXAMPLE 5

Example 1 is reproduced, using on the one hand 0.012 g (0.565 mmol) of ABAA (240 molar ppm relative to the monomers), and on the other hand an aqueous phase containing a total of 424 g of water instead of 432 g. There is thus obtained, after addition of 116.7 g of TYLOSE® C 1000, 1131.7 g of a dispersion designated D ₅ , containing by weight 4% of surfactants, 22.8% of oil, 37.5% of water and 35.8% of a mixture of anionic polymers containing by weight 28.8% of carboxymethylcellulose and 71.2% of an AA-AAK-AMPSK copolymer, 25.5 - 59.5 - 15 in molar proportions , crosslinked with 240 molar ppm of ABAA. The intermediate dispersion before the introduction of the carboxymethylcellulose is designated D ₂₅ . In another test, 165.4 g of TYLOSE® C 1000 are used instead of 116.7 g. 1,189.4 g of a dispersion are thus obtained, designated D ₄₅ . The rheological and application characteristics of these dispersions are mentioned in the following tables.

EXAMPLE 6

Example 2 is reproduced, using on the one hand, 0.145 g (0.7316 mmol) of ABAA (240 ppm molar relative to the monomers) and on the other hand an oil phase containing 225 g of oil S 8515 and 22.5 g of sorbitan sesquioleate. One thus obtains after addition of 114.5 g of TYLOSE® C 1000, 1110 g of a dispersion designated D ₆ , the intermediate dispersion before the introduction of the carboxymethylcellulose is designated D ₂₆ . In another test, 229 g of TYLOSE® C 1000 are introduced into the dispersion D ₂₆ and 1224.5 g of a dispersion designated D ₄₆ are obtained. The rheological and application characteristics of these dispersions are mentioned in the following tables.

• Ex : exemple.
• ABAA ppm : indique le nombre de moles d'ABAA pour 10⁶ moles de monomères.
• C : polymère anionique, du type des carboxyméthylcelluloses sodiques, C 1000 indique la TYLOSE® C 1 000 et C 300 indique la TYLOSE® C 300, commercialisées par la demanderesse ; leur pourcentage en poids est calculé par rapport au poids total de la composition selon l'invention.
• Les pourcentages pondéraux des polymères présents dans la composition de l'invention sont exprimés en sec. Ainsi, 35,6 indiqué pour la dispersion D₁, du tableau I, signifie que la composition contient 35,6 % d'un mélange de polymères anioniques, dont 10,31 % par rapport au poids total de la composition de la TYLOSE® C 1 000, et en conséquence 35,6 - 10,3 = 25,3 % d'un polymère AA-AAK-AMPSK, 25,5 - 59,5 - 15.
• T.A : tensioactifs présents dans la composition.
• Ref : indique une pâte d'impression préparée avec de l'alginate de sodium comme indiqué dans la présente description.
• Les caractéristiques des impressions sont notées de 0 à 5, de mauvaise à excellente, la note 3 est la qualité obtenue avec une pâte conventionnelle préparée avec de l'alginate de sodium.
• G* : module complexe, il est exprimé en Pascal.
• δ : angle de perte, il est exprimé en degré et il est calculé par la relation : tan δ = G''/G' où G' représente le module de conservation (storage modulus) et G" le module de perte (loss modulus).
• Les dispersions D₂₁, D₂₂, D₂₃, D₂₄, D₂₅ et D₂₆ sont des dispersions utilisées pour préparer les compositions de l'invention ; leurs caractéristiques sont indiquées à titre de comparaison.

In Tables I to III, the abbreviations used have the following meanings:

• Example: example.
• ABAA ppm: indicates the number of moles of ABAA per 10 ⁶ moles of monomers.
• C: anionic polymer, of the sodium carboxymethylcellulose type, C 1000 indicates TYLOSE® C 1000 and C 300 indicates TYLOSE® C 300, sold by the applicant; their percentage by weight is calculated relative to the total weight of the composition according to the invention.
• The weight percentages of the polymers present in the composition of the invention are expressed in sec. Thus, 35.6 indicated for dispersion D ₁ , in Table I, means that the composition contains 35.6% of a mixture of anionic polymers, of which 10.31% relative to the total weight of the composition of TYLOSE® C 1000, and consequently 35.6 - 10.3 = 25.3% of an AA-AAK-AMPSK polymer, 25.5 - 59.5 - 15.
• TA: surfactants present in the composition.
• Ref: indicates a printing paste prepared with sodium alginate as indicated in the present description.
• The characteristics of the impressions are marked from 0 to 5, from poor to excellent, note 3 is the quality obtained with a conventional paste prepared with sodium alginate.
• G *: complex module, it is expressed in Pascal.
• δ: loss angle, it is expressed in degrees and it is calculated by the relation: tan δ = G '' / G 'where G' represents the conservation module (storage modulus) and G "the loss module (loss modulus) ).
• The dispersions D ₂₁ , D ₂₂ , D ₂₃ , D ₂₄ , D ₂₅ and D ₂₆ are dispersions used to prepare the compositions of the invention; their characteristics are shown for comparison.

Rhéologie Caractéristiques des impressions N° G*^(Pa) δ (°) To Re Un Ref 7 85 3 3 3 D₂₁ 56 10 3 3 3 D₁ 12 37 3 4 3 D₂₂ 16 28 3 3 3 D₂ 7 44 3 5 3 D₃₂ 6 50 D₂₃ D₃ 8 37 3 4 3 D₃₃ 16 29 3 4 3 D₂₄ 6 73 3 3 3 D₄ 4 70 3 5 3 D₂₅ 86 12 D₅ 12 38 3 4 3 D₄₅ 13 40 3 4 3 D₂₆ 10 42 3 3 3 D₆ 7 52 3 4 3 D₄₆ 5 56 3 5 3 The analysis of Table III shows that the printing pastes produced with the compositions of the invention have application properties greater than or equal to those obtained by the use of printing pastes prepared either conventionally with l sodium alginate, or only with synthetic polymers based on acrylic acid.

Rheology Print specifications No. G * ^(Pa) δ (°) To Re A Ref 7 85 3 3 3 D ₂₁ 56 10 3 3 3 D ₁ 12 37 3 4 3 D ₂₂ 16 28 3 3 3 D ₂ 7 44 3 5 3 D ₃₂ 6 50 D ₂₃ D ₃ 8 37 3 4 3 D ₃₃ 16 29 3 4 3 D ₂₄ 6 73 3 3 3 D ₄ 4 70 3 5 3 D ₂₅ 86 12 D ₅ 12 38 3 4 3 D ₄₅ 13 40 3 4 3 D ₂₆ 10 42 3 3 3 D ₆ 7 52 3 4 3 D ₄₆ 5 56 3 5 3

Claims (11)

1. Self-reversible, stable, water-in-oil dispersions, miscible with water, constituted by an oil phase, an aqueous phase and at least two emulsifying agents of which at least one is of water-in-oil type, and at least one is of oil-in-water type, characterized in that, in relation to the total weight of dispertions, the oil phase represents 15 to 35% by weight and the water 25 to 60%, and in that they contain 20 to 50% by weight of a mixture constituted by a hydrosoluble anionic polymer belonging to the group of carboxymethylcelluloses, designated C, and by a cross-linked, synthetic anionic polymer, insoluble in water but water-swellable, designated P, based on acrylic acid, designated AA, partially salified with an alkali metal, designated M, optionally copolymerized with 2-acrylamido 2-methyl propanesulphonate of the alkali metal M, designated AMPSM, cross-linked with a diethylenic carboxylic acid and in which the molar ratio of the salified acid functions to the total number of free or salified acid functions is comprised between about 0.6 and about 0.9, the ratio by weight C/P+C being comprised between 0.01 and 0.5, M being chosen from sodium and potassium.
2. Dispersions according to claim 1, characterized in that they contain from 20 to 50% by weight of a mixture of anionic polymers constituted by 10 to 50% by weight of a carboxymethylcellulose, C, and by 90 to 50% by weight of a cross-linked polymer, P, AA-AAM-AMPSM containing in molar proportions 0 to 30% of AMPSM and 100 to 70% of an AA and AAM mixture containing in molar proportions 20 to 40% of AA and 80 to 60% of AAM, cross-linked with 0.01 to 0.06% in molar proportions relative to the monomers used, of a diethylenic carboxylic acid chosen from the group constituted by bisacrylamidoacetic acid and diallyloxyacetic acid.
3. Dispersions according to any one of claims 1 and 2, characterized in that the polymer P is cross-linked with bisacrylamidoacetic acid.
4. Dispersions according to any one of claims 1 to 3, characterized in that the polymer P is a cross-linked polymer, AA-AAM-AMPSM, containing in molar proportions 10 to 30% of AMPSM and 90 to 70% of acrylic acid and of which 60 to 80% are in the form of an alkali metal acrylate.
5. Dispersions according to any one of claims 1 to 3, characterized in that the polymer P is a cross-linked polymer, AA-AAM, containing in molar proportions 30 to 40% of AA and 70 to 60% of AAM.
6. Dispersions according to any one of claims 1 to 5, characterized in that they contain by weight 10 to 20% of a sodium carboxymethylcellulose and 20 to 30% of a polymer P.
7. Dispersions according to any one of claims 1 to 6, characterized in that they contain by weight, in relation to the total weight of dispertions, 2 to 10% by weight of a mixture of emulsifying agents, of which 40 to 60% are constituted by one or more emulsifying agents of water-in-oil type and 60 to 40% are constituted by one or more emulsifying agents of oil-in-water type.
8. Process for obtaining a dispersion according to one of claims 1 to 7, characterized in that a radical polymerization reaction in a water-in-oil emulsion is carried out, starting with an aqueous solution containing the constitutive monomers of polymer P, and optionally a chelating agent, which is emulsified in an oil phase in the presence of one or more emulsifying agents of water-in-oil type, the polymerization reaction being initiated by the introduction into the starting emulsion of a product generating free radicals or a Redox pair, then, when the polymerization reaction is completed, one or more emulsifying agents of oil-in-water type and the desired quantity of anionic polymer C are introduced into the dispersion obtained, at a temperature of less than 30°C.
9. Process according to claim 8, characterized in that the polymerization is initiated by a Redox pair, at a temperature lower than or equal to 10°C, then it is taken in a quasi-adiabatic manner to a temperature higher than or equal to 60°C.
10. Process according to one of claims 8 and 9, characterized in that the polymerization reaction is initiated by a cumene hydroperoxide - sodium bisulphite Redox pair, at a dose of 10 to 100 molar ppm relative to the cumene hydroperoxide monomers and of 20 to 100 molar ppm relative to the sodium bisulphite monomers.
11. Use, in the textile industry, of a dispersion according to any one of claims 1 to 7 for obtaining a printing paste containing one or more reactive dyes.