EP0165136B1 - Detergent compositions containing copolymers based on polyoxyethylene and polyoxyalkylene used as antisoil redeposition agents, and process for their preparation - Google Patents

Description

The present invention relates to polyoxyalkylene-based copolymers used as anti-deposition agents in the washing of textiles.

These copolymers are used more particularly as an antiredepositing agent for washing in aqueous medium of polymeric, organic and synthetic materials.

It is known that polymeric, synthetic organic materials are difficult to clean in an aqueous medium. In fact, during successive washes, the particles of dirt suspended in the detergent medium are permanently and almost irreparably deposited on these textiles, the consequence is that these textiles lose their whiteness and their luster over time in a very more marked than natural textiles such as cotton.

The present invention which has overcome all these technical problems relates to detergent compositions according to claim 1 below.

Throughout the rest of the text, the term zeta potential is understood to mean the absolute value of this parameter.

The copolymers which meet the definition of the invention all preferably have a molecular weight less than or equal to 150,000 and even more preferably between 2000 and 150,000 and even more particularly between 4000 and 100,000.

The copolymers according to the invention preferably comprise an amount by weight of ethylene oxide relative to the polymer of between 10% and 90% and even more preferably an amount between 30 and 90% and very particularly an amount between 40 and 70%.

The ethylene oxide groups constitute the hydrophilic part of the copolymer and therefore allow the solubilization of the copolymer in water which is essential for a detergency application in an aqueous medium. The alkylene oxide groups constitute the hydrophobic part of the copolymers and allow the adsorption of the copolymer on the fiber made up of synthetic organic polymers. This adsorption of the copolymer on the fiber will allow the desired effect, that is to say the anti-deposition.

According to US Pat. No. 4,118,344, a composition for dry cleaning is known, based in particular on an ethylene-propylene polyglycol in solution in a solvent of the hydrocarbon type.

The cited reference relates to compositions for dry cleaning in a solvent medium and not for washing in an aqueous medium.

A first group of anti-depositing copolymers used in the prior art consists of copolymers composed of linear or branched polyoxyethylene and polyoxyalkylene blocks of alkylene oxide containing in particular from 3 to 6 carbon atoms per alkylene group. The alkylene groups are preferably propylene or butylene groups.

These copolymers marketed under the brand name "PLURONICS""are prepared in a known manner, for example according to the process described in US Patent No. 2,674,619. They are used for the most part and essentially for polyoxyethylene-polyoxyalkylene copolymers as removal agent dirt, according to US Patent No. 4,276,205, for example, which relates to compositions based on an amine oxide, an ethoxylated alcohol or an ethoxylated alkylphenol and a condensation product d alkylene oxides - C _2- C ₄ .

These compositions are presented as having a significant soil removal effect, in particular for greases, the amine oxide promoting the liquefaction of these.

dans laquelle:

• - R, R₂ R₃ R₄ R_s R₆ représentent des polymères choisis parmi les homopolymères polyoxyéthylène, polyoxyalkylène linéaires ou ramifiés d'oxyde d'alkylène contenant de 3 à 6 atomes de carbone et les copolymères blocs linéaires ou ramifiés de ces polyoxyéthylène polyoxyalkylène.
• - n, m et p sont des nombres entiers égaux ou supérieurs à 0 et égaux ou inférieurs à 10 et de préférence dont la somme n + m + p est comprise entre 1 et 20 et avantageusement entre 1 et 5.

A second group of copolymers consists of copolymers which correspond to the general formula (1 \

in which:

• - R, R ₂ R ₃ R ₄ R _s R ₆ represent polymers chosen from linear or branched polyoxyethylene, polyoxyalkylene homopolymers of alkylene oxide containing from 3 to 6 carbon atoms and linear or branched block copolymers of these polyoxyethylene polyoxyalkylene.
• - n, m and p are whole numbers equal to or greater than 0 and equal to or less than 10 and preferably the sum of which n + m + p is between 1 and 20 and advantageously between 1 and 5.

It is more particularly preferred to use the compounds for which p = 0, m = 0 and n = 1.

The polyoxyalkylene groups are preferably chosen from polyoxypropylene and polyoxybutylene.

The copolymers of formula (I) can optionally be made ionizable by quaternizing the nitrogen atom (s). This quaternization can be carried out for example by a hydrogen atom or by an alkyl group.

Some of these copolymers are marketed under the name TETRONIC.

They are used in the same way as PLURONICS '"as a soil-removing agent and as an anti-depositing agent, in particular according to patent application EP 42 187.

dans laquelle:

• - R₇, R₈ représentent un groupe méthyle ou des polymères choisis parmi les homopolymères polyoxyéthylène-polyoxyalkylène linéaires ou ramifiés d'oxyde d'alkylène contenant notamment de 3 à 6 atomes de carbone et les copolymères blocs linéaires ou ramifiés polyoxyéthylène-polyoxyalkylène.
• - a est un nombre entier compris entre 1 et 150
• - au moins un atome de silicium porte un groupe choisi parmi R₇ et R_e.

A third group of copolymers consists of copolymers which correspond to the general formula (II)

in which:

• - R ₇ , R ₈ represent a methyl group or polymers chosen from linear or branched polyoxyethylene-polyoxyalkylene homopolymers of alkylene oxide containing in particular from 3 to 6 carbon atoms and linear or branched polyoxyethylene-polyoxyalkylene block copolymers.
• - a is an integer between 1 and 150
• - At least one silicon atom carries a group chosen from R ₇ and R _e .

The copolymers of formula (II) sold are prepared in a manner known per se, for example described in US Patent No. 2,970,150, Example 16.

dans laquelle

• - R₉ et R₁₀ représentent des homopolymères d'oxyde d'éthylène, d'oxyde d'alkylène contenant de 3 à 6 atomes de carbone linéaires ou ramifiés ou des copolymères blocs linéaires ou ramifiés de ces polyoxyéthylène-polyoxyalkylène, et
• - A représente un radical alkylène ou phénylène éventuellement substitué; ces copolymères réduisent le potentiel zêta d'un tissu en matière polymérique organique synthétique à une valeur inférieure ou égale à 0,5 fois le potentiel zêta de la fibre nue, le potentiel zêta étant mesuré par contact du tissu avec une solution de NaCI à 3 g/l à pH 7 et dans des conditions telles que la quantité de copolymère adsorbé par gramme de tissu soit au minimum de 0,02 mg.

The group of copolymers which are the subject of the invention consists of block copolymers formed by a chain of units corresponding to the general formula (III)

in which

• R ₉ and R ₁₀ represent homopolymers of ethylene oxide, of alkylene oxide containing from 3 to 6 linear or branched carbon atoms or linear or branched block copolymers of these polyoxyethylene-polyoxyalkylene, and
• - A represents an optionally substituted alkylene or phenylene radical; these copolymers reduce the zeta potential of a fabric of synthetic organic polymeric material to a value less than or equal to 0.5 times the zeta potential of the bare fiber, the zeta potential being measured by contact of the fabric with a NaCl solution at 3 g / l at pH 7 and under conditions such that the amount of copolymer adsorbed per gram of tissue is at least 0.02 mg.

These polyoxyalkylenes can be chosen in particular from polyoxypropylenes.

British Patent No. 2,007,692 describes an anti-depositing composition for polyester.

• -d'un polyuréthane hydrophile et/ou d'un copo- lyester,
• - d'un polyoxyéthylèneglycol ou d'un polyoxyéthylène alcool ou phénol,
• -d'un acide gras ou d'une cire microcristalline.

This composition consists of:

• -a hydrophilic polyurethane and / or a copolyester,
• - a polyoxyethylene glycol or a polyoxyethylene alcohol or phenol,
• -a fatty acid or a microcrystalline wax.

This composition does not correspond to the copolymers of formula (III).

French Patent No. 2,308,646 describes polyurethanes having an anti-redeposition action for polyester-cotton fibers.

• - diisocyanate organique,
• - d'un mélange de polyoxyéthylèneglycol et éventuellement d'un diol,
• - d'un composé azoté de formule:
  
  dans laquelle R est un radical alkyle et X représente des radicaux hydroxy alkyle ou amine alkyle ne correspondent pas aux copolymères de formule (III) objet de la présente invention.

The polyurethanes which are the subject of the French patent obtained by reaction of:

• - organic diisocyanate,
• - a mixture of polyoxyethylene glycol and optionally a diol,
• - a nitrogenous compound of formula:
  
  in which R is an alkyl radical and X represents hydroxy alkyl or amine alkyl radicals which do not correspond to the copolymers of formula (III) which are the subject of the present invention.

Among the copolymers of formula (III), mention may be made of those for which A represents a hexamethylene, toluylene, isophorone, diphenylalkane radical.

It is particularly preferred to use the copolymers of formula (III) in which A is a hexamethylene or toluylene radical.

According to the invention, it is preferred to use, among the copolymers of formula (III), those which have: a molecular mass of between 4000 and 40,000 and very particularly between 4000 and 25,000, a weight amount of ethylene oxide of between 40 and 50%, polyoxyethylene blocks with molecular weights less than 3500 and even more preferably between 550 and 1600 and polyoxyalkylene blocks with molecular masses less than 4000 and preferably between 500 and 2000.

The copolymers of formula (III) are obtained for example by condensation of polyoxyethylene, of polyoxyalkylene of alkylene oxide of 3 to 6 carbon atoms or of block copolymers of polyoxyethylene-polyoxyalkylene with diisocyanates chosen from hexamethylene diisocyanate, toluylene diisocyanate, isophorone diisocyanate, di (isocyanatophenyl) alkanes, in an anhydrous medium in the presence of tin salt.

The copolymers obtained by condensation of the homopolymers with diisocyanates have markedly improved anti-depositing properties.

The copolymers described above can be used according to the invention as anti-depositing agents when they lower the zeta potential of the textile fiber to a value less than or equal to 0.5 times the zeta potential of the bare fiber. This decrease in zeta potential is a function of the amount of copolymer adsorbed. This amount must be greater than 0.02 mg / g.

The quantity adsorbed is measured by bringing a sample of fabric made of polymeric, organic, synthetic material (TERGAL "type) of a mass close to 3.5 g fixed on a metal support, with 100 ml of a NaCl solution. (3 g / l) containing the polymer, in a cell thermostatically controlled at 25 ° C. The medium is stirred When the adsorption equilibrium is reached, the quantity adsorbed is determined by an assay of the concentration of polymer remaining in solution according to the method described by BALEUX (CR Acad. Sc., 274 series C, (1972), 1617).

The zeta potential of the fiber is measured before contact with the copolymer and after contact.

The measurements of zeta potential, or electrokinetic potential, are carried out by the method of flow potential: a NaCl solution 3 g / 1 (pH = 7) containing or not the polymer circulates under the effect of a pressure through a stamp consisting of several rings of su fabric perposed. The variation of the potential difference at the ends of the buffer as a function of the pressure applied to the solution makes it possible to determine the zeta potential of the fibers (JS STANLEY J. Phys. Chem. 58, (1954), 533).

Before measuring the electrokinetic potential, the tissue washers are brought into contact for 24 hours with a polymer solution in NaCl 3 g / l medium, so as to adsorb the copolymer on the fibers. After this adsorption phase, the tissue washers are placed in the filter of the apparatus and the copolymer solution used during the adsorption period circulates under the effect of a pressure through the tissue pad.

The operation is carried out in the same way with fabric washers not impregnated with copolymer.

The anti-depositing effect of the copolymer can be measured by a series of different tests in the presence of dirt.

It is not obvious, on reading the prior art, to relate the effectiveness of the copolymer and therefore its antiredepositing effect to the zeta potential of the fiber in polymeric, organic, synthetic material on which the copolymer is adsorbed.

It has been discovered by the present invention that the anti-depositing effect is achieved when the zeta potential of the fiber on which the copolymer is adsorbed is equal to or less than 0.5 times that of the bare fiber.

This reduction in zeta potential is achieved for amounts of adsorbed copolymer equal to or greater than 0.02 mg / g of tissue. The preferred amount of adsorbed copolymer varies with the type of adsorbed copolymer.

For the copolymers corresponding to the general formula (III), the preferred amount of adsorbed copolymer is between 0.05 and 5 mg / g of tissue.

The invention will now be described more fully without however limiting its scope, using the anti-redeposition tests used and the examples which follow.

Anti-deposition tests used Test # 2

The anti-depositing efficacy of an additive is evaluated by carrying out five cumulative “Terg-O-Tometer” washing cycles (United States Testing Company Inc. Hobokin, NJ) in the presence of “complete” soiling.

Each cycle consists of a 20-minute washing phase (1 1 of solution per pot, T = 60 ° C) and a five-minute rinse in cold hard water. Soiling is introduced into each pot five minutes after the start of each cycle. The hardness of the water used is 32 ° excl.

• 100 g Sebum
• 4 g Acide oléique
• 8 g Triethanolamine
• 4 g Salissure particulaire
• 884 g Eau
• La composition du sébum est la suivante: 10% Acide palmitique
• 5% Acide stéarique technique
• 10% Acide oléique purifié
• 5% Acide linoléique
• 15% Huile de Coprah
• 20% Huile d'olive vierge
• 5% Squalène 90%
• 10% Paraffine raffinée 52/54
• 15% Blanc de baleine
• 5% Cholesterol

The soiling used is of the “Spangler” type (WG SPANGLER, HD CROSS and BR SCHAAFSMA, J. Am. Oil Chemist's Soc. 42 (1965), 723), it consists of:

• 100 g Sebum
• 4 g Oleic acid
• 8 g Triethanolamine
• 4 g Particulate soiling
• 884 g Water
• The composition of the sebum is as follows: 10% Palmitic acid
• 5% Technical stearic acid
• 10% Purified oleic acid
• 5% Linoleic acid
• 15% Copra Oil
• 20% virgin olive oil
• 5% Squalene 90%
• 10% Refined paraffin 52/54
• 15% Whale white
• 5% Cholesterol

• 86% Kaolin
• 8% Noir de fumée
• 4% Oxyde de fer noir
• 2% Oxyde de fer jaune.

The composition of the particulate soiling is as follows:

• 86% Kaolin
• 8% Smoke black
• 4% Black iron oxide
• 2% Yellow iron oxide.

The total soil concentration used is 50 g / I for each wash cycle.

The liquor used in concentration of 6 g / l, its weight com _D osition is:

The fabric samples used during our washing tests are polyester samples ("DACRON" 54 "from TESTFABRIC) washed beforehand at 60 ° C in a machine supplied with fresh water and in the absence of detergent. Each jar of" Terg -O-Tometer ”contains 6 fabric rectangles (10 x 12 cm).

The concentration of anti-depositing additive used is 50 mg / 1. The redeposition is quantified by the difference AR (measured by a GARDNER photometer "", filter Y) between the reflectance of the initially clean fabric and that of the fabric after five washing cycles. The anti-depositing agent is all the more effective when ΔR is low.

Test # 3

The experimental conditions used during this test are identical to those of the previous test, with the difference that the soiling is no longer a liquid soiling of the “Spangler” type but a soiling impregnated on cotton samples (“WFK Testgewebe GmbH KREFELD ”). Before each washing cycle, three rectangles (10 x 12 cm) of soiled cotton are placed in each pot.

For tests 2 and 3, it can be considered that an additive has a significant anti-depositing effect if the value of AR is reduced by at least 3 points in the presence of the polymer compared to the value of AR measured in the absence of additive.

The values of the ratio ξ / ξ _o (ξ is the zeta potential of the fiber in the presence of copolymer and ξ _o represents the zeta potential of the bare fiber) and of the amount adsorbed per gram of tissue, indicated in the examples below , were determined under conditions where the quantity adsorbed is close to its maximum value, which corresponds, under the experimental conditions used, to copolymer concentrations within the solution of the order of 10 mg / 1.

Examples 1 to 39 Products corresponding to the general formula (III)

Examples 1 to 14 were carried out using copolymers obtained by condensation of PLURONICS "by means of hexamethylene diisocyanate (HDI) at a temperature between 80 and 105 ° C. in the optional presence of a catalyst such as dilaurate dibutyltin Tests 1 to 14 are reported in Table 1a.

These products have an anti-depositing effect and lead to values of ξ / ξ _o less than 0.5. They meet the criteria of the invention.

Examples 15 to 39 were carried out using copolymers obtained by condensation of polyoxyethylene and another polyoxyalkylene in the presence of hexamethylene diisocyanate. Tests 15 to 39 are reported in Table 1b, 1c and 1d.

It is noted that particularly good results are obtained for the copolymers having a weight amount of ethylene oxide of between 40 and 50% and a molecular weight of between 4000 and 25,000. This is the case of tests 19, 20, 21, 35 and 36.

The invention also relates to the preparation of detergent compositions comprising the copolymers of the type described above, a simple and effective preparation process has been developed.

The process for the preparation of detergent compositions of the type of the invention is characterized in that the anti-depositing copolymer is added to a slurry comprising other constituents of the compositions, the mixture thus obtained is then dried.

It has been observed that the copolymer thus introduced retains all of these properties in the composition obtained. This is an advantageous advantage because the copolymers of the invention can be used without appreciably modifying the conventional methods of preparation of detergent compositions.

The preparation of the slurry is done in a manner known per se. The copolymer is added thereto with stirring. The mixture obtained is then dried by any suitable means.

Any dry additive used in detergent compositions can be mixed with the dry product thus obtained: bleaching agents, anti-foaming agent, perfumes, dyes, enzymes for example.

The amount of copolymer added is such that it represents in particular approximately 0.2 to 5% and preferably between 1 and 2% by weight of the final composition.

When added to the slurry, the copolymer can be presented in different forms.

A first possibility consists in presenting the copolymer in the form of a solution in water. In such a case, the concentration of copolymer in the solution is between 5 and 20% and preferably 10 to 15%.

Another possibility is to prepare a solution of the copolymer in a water-alcohol mixture.

As alcohol, one can use an aliphatic alcohol such as for example ethanol or a compound which can be used in detergency as a nonionic surfactant such as for example polyoxyethylenated alkylphenols, polyoxyethylenated aliphatic alcohols, glycols and polyglycols.

Generally a mixture of 40-60% of copolymer, 20-50% of water, 5-15% of alcohol is used, preferably 50% of copolymer, 40% of water, 10% of alcohol.

It is also possible to present the copolymer on a support. In this case, a suitable silica can be used as support, for example a silica of the TIXOSIL "38A type.

It is also possible to use mixtures of the copolymer and of sulfonic acids such as for example arylsulfonic, alkylsulfonic, alkylarylsulfonic acids, in particular linear alkylbenzene sulfonic acids.

An example of preparation of a composition according to the invention will now be given.

The various constituents of the composition are given below with the percentages by weight. Sodium alkylbenzene sulfonate

First of all, a slurry is prepared comprising LABS and sodium sulfate, stearate, silicate and tripolyphosphate, with stirring for 20 minutes at 85-90 ° C.

We then operate in 3 cases.

CASE 1

In the first case, the antiredepositing agent according to the invention is not added to the formulation. The slurry is then dried at 4 hours at 150 ° C. and then mixed with the other constituents of the composition.

CASE 2

In this case, an antiredeposition agent is added with stirring for 15 minutes at 80 ° C. in the form of a 10% solution in water according to the invention. This agent is that corresponding to Example 20 (copolymer obtained by condensation of polyoxyethylene and polyoxyalkylene in the presence of hexamethylene diisocyanate). The slurry thus prepared is mixed after drying (4 hours at 150 ° C) with the other components of the composition.

CASE 3

In this case, no more anti-depositing agent is added and the procedure is as in the first case. However, the same agent is added as in case 2 to the washing medium before each washing cycle.

Washings and reflectance measurements are then carried out according to the conditions of test 3 of the main patent.

In cases 2 and 3, the amount of anti-depositing agent used represents 1% of the total weight of the composition. The concentration of the washing composition is 6 g / l.

The reflectance Ry of the textile is evaluated after washing. The higher the reflectance Ry, the lower the redeposition. The results are given below:

It is therefore seen by comparing cases 2 and 3 that the anti-redeposition agent according to the invention can therefore completely be incorporated into a slurry without any significant impact on its properties.

Of course, it is understood that the preparation process which has just been described is only a particular and advantageous process, it is quite possible to envisage other processes for preparing the compositions described above without going out of the scope of the invention.

Furthermore, the invention is in no way limited to the embodiments described which have been given only by way of examples. In particular, it includes all the means constituting technical equivalents of the means described as well as their combinations if these are used in the context of protection as claimed.

Claims (13)

1. Detergent compositions containing an antiredeposition copolymer which is useful for washing synthetic organic polymeric materials characterised in that said polymer is formed by block copolymers formed by a chain of units corresponding to following general formula (III):

wherein

- Rg and R₁₀ represent straight or branched chain ethylene oxide/alkylene oxide homopolymers containing from 3 to 6 carbon atoms or branched or straight chain block copolymers of those polyoxyethylene-polyoxyalkylenes, and

- A represents an alkylene or phenylene radical which is optionally substituted; and reduces the zeta potential of a textile of synthetic organic polymeric material to a value of less than or equal to 0.5 times the zetal potential of the bare fibre, the zeta potential being measured by contact of the material with a solution of NaCI with 3 g/I and with a pH-value of 7 and under conditions such that the amount of copolymer adsorbed per gram of textile material is at a minimum 0.02 mg.

2. Compositions according to claim 1, characterised in that the polyoxyalkylenes are polyoxypropylenes.

3. Compositions according to claims 1 to 2, characterised in that the copolymers have a molecular weight of between 4,000 and 25,000.

4. Compositions according to claims 1 to 3, characterised in that the copolymers comprise an amount by weight of ethylene oxide of between 40 and 50%.

5. Compositions according to claims 1 to 4, characterised in that the copolymers comprise polyoxyethylene sequences of a molecular weight of lower than 3,500 and preferably between 550 and 1,600.

6. Compositions according to claims 1 to 4, characterised in that the copolymers comprise sequences of polyoxyalkylene derived from alkylene oxide containing from 3 to 6 carbon atoms, of a molecular weight of lower than 4,000 and preferably between 500 and 2,000.

7. Compositions according to claim 1, characterised in that the copolymer reduces the zeta potential of the fibre which is measured at a pH-value of 7 in a 3 g/I NaCI solution to a value of less than 0.5 times that of the zeta potential of the bare fibre measured under conditions such that the amount of copolymer adsorbed is between 0.05 and 5 mg/g.

8. A process for the preparation of detergent compositions according to any one of the preceding claims, characterised in that the antiredeposition copolymer is added to a slurry comprising other constituents of the composition and that the mixture obtained is then dried.

9. A process according to claim 8, characterised in that the copolymer is added to the slurry in the form of a solution in water.

10. A process according to claim 8, characterised in that the copolymer is added to the slurry in the form of a solution in a water-alcohol mixture.

11. A process according to claim 10, characterised in that the alcohol used is a compound which can be employed as a non-ionic surface active agent.

12. A process according to claim 8, characterised in that the copolymer added is presented on a silica carrier.

13. A process according to claim 8, characterised in that the copolymer added is presented in the form of a mixture with a compound selected from the group of sulphonic acids.