EP0279134A1 - Antiredeposition latex for washing textiles - Google Patents

Abstract

Anti-fouling and anti-depositing latex used in the aqueous washing of textile materials, consisting either of vinyl acetate copolymers of unsaturated carboxylic acids optionally grafted with sulphonic polyesters or of (meth) acrylic composites grafted with sulphonic polyesters.

Description

The present invention relates to new latexes used as anti-fouling and anti-deposition agents for the aqueous washing of textile articles.

It is known that the detergent compositions currently marketed for washing synthetic or natural textile articles are complex mixtures of different products all having well-defined functions, such as, for example, metal complexing agents, surfactants, anticorrosion agents, detergents, anti-depositing agents, bleaching agents or anti-fouling agents.

Antifouling agents are understood to mean agents which essentially have the role of reducing the affinity of textile fibers for soiling, in particular for greasy soiling, and thus facilitating their removal.

The term “anti-depositing agents” is intended to mean agents which essentially have the role of preventing the deposition of soiling on the textile fibers, in particular to avoid the redeposition of the soiling removed during washing.

The main object of the invention is new agents with anti-deposition and soil removal properties which are particularly effective and relatively inexpensive.

Another subject of the invention relates to washing compositions using these new anti-fouling agents.

In this text and for the remainder of the description, the term "latex" has the usual meaning, that is to say, the aqueous dispersions of polymers forming heterogeneous systems comprising a continuous liquid phase, water and a solid discontinuous phase. .

The alkali-soluble latexes of the invention which are the subject of the patent application are latexes in the dispersion state at a certain pH, in particular acidic or neutral, and which, when the pH increases, see the above-mentioned polymerized particles disintegrate. , which thus leads to aqueous solutions of polymers. In other words, the latexes which are suitable in the context of the invention are those which during increases in pH are likely to undergo a variation in their configuration depending on the pH of the detergent bath.

The alkali-soluble latexes used are generally well known products. Their preparation, their physical and chemical characteristics are considered here as part of the prior art.

The object of the present invention has been to select, from the range of latexes described, a field of latex compositions, on the one hand, which can be synthesized at low cost and which, on the other hand, have improved anti-fouling and anti-fouling properties compared with the latexes described in the prior art.

The latexes which are the subject of the present application are all vinyl latexes either composed of vinyl acetate-unsaturated carboxylic acid copolymers optionally grafted with sulfonic polyesters or of (meth) acrylic-carboxylic acid copolymers grafted with sulfonic polyesters.

As the first type of alkali-soluble latex which is very suitable in the context of the present invention, mention may be made of latexes based on vinyl esters. More particularly, it is possible to use the latexes based on vinyl esters, on ethylenically unsaturated mono or dicarboxylic acids and optionally either (meth) acrylic esters or of water-soluble monomers such as acrylamide or vinyl sulfonate. By way of acid, mention will in particular be made of maleic, crotonic, (meth) acrylic or itaconic acids. Generally, the acid level is at least 3% and preferably between 3 and 8%. As vinyl ester, particular mention will be made of vinyl acetate.

The first type of alkali-soluble latex which is the subject of the present invention also consists of the latexes based on vinyl esters, previously described, polymerized in the presence of polyester sulfonate.

The second type of alkali-soluble latex, object of the present invention, consists of (meth) acrylic esters and of carboxylic acids grafted with polyester sulfonates.

In this case, it is possible to use latexes based on (meth) acrylic esters, on mono or dicarboxylic acids, ethylenically unsaturated and optionally other monomers such as styrene or butadiene.

As (meth) acrylic esters, mention may in particular be made of alkyl (meth) acrylates, the alkyl chain of which preferably contains 1 to 4 carbon atoms such as methyl or ethyl (meth) acrylate.

As acids, mention may be made particularly of (meth) acrylic, itaconic or maleic acids.

In principle, the acid content (percentage by weight of monomer in the product) is at least 10% and generally it is between 10% and 20%.

The level of polyestersulfonate relative to the monomers is preferably less than 10%. The sulfonated polyesters used even more preferably in the context of the present invention are those containing approximately 60% of phthalyl or succinyl group for approximately 40% of ethylene oxide group. Phthalic acid is distributed between its isomers approximately as follows: 80% terephthalic acid for 20% isophthalic acid. A molar quantity of sulfoisophthalic acid corresponding to approximately 15% of the previously indicated acid mixture is added to this acid mixture.

The latexes which are the subject of the present invention are preferably chosen from those of the first group of alkali-soluble latexes which have a composition which corresponds to the following distribution:
- 84 to 96% vinyl acetate,
- 3 to 6% of acrylic or crotonic acid or one of its derivatives and
- 1 to 10% of sulfonated polyester.

It is preferred to use latexes whose composition is within the following limits:
- vinyl acetate 87 - 94%
- crotonic or acrylic acid 4 - 5%
- sulfonated polyester 2 - 8%
and especially latexes whose acid is acrylic acid.

Also forming part of the invention, the preceding products having undergone partial or total hydrolysis of the vinyl acetate groups, that is to say a transformation of vinyl acetate into vinyl alcohol.

The detergent compositions containing said latex also form part of the invention, they preferably contain at least 0.1% of latex as described above and even more preferably 0.4%.

The detergent compositions may also contain, as washing auxiliaries, pyrophosphates, metaphosphates, tripolyphosphates of alkali metals, zeolites, surfactants, a bleaching system, enzymes, optical brighteners, perfumes, silicates etc .....

The latex can also be incorporated into a rinsing composition, which of course makes it possible to add the latex to the bath during rinsing.

Of course, all that has been said above in the description concerning the nature and characteristics of the alkali-soluble latex applies here to the subject of the compositions, the latexes entering into their constitutions being completely identical to those described for the process.

Examples will now be given.

The tests used in the examples which follow are intended to evaluate the anti-fouling and anti-depositing properties of a given additive.

The redeposition of soiling is a cumulative phenomenon which manifests itself by graying of the laundry after a significant number of washing cycles.

EXAMPLES 1 to 4

To measure the anti-depositing properties, the method used consists of washing tissue samples several times in the presence of the additive to be tested, and of soiled tissue. The experimental conditions are as follows:

OPERATING CONDITIONS :

Five cumulative washing cycles are carried out under the following conditions:
- Washing temperature: 60 ° C
- Washing time: 20 min (7 min rise in temperature and 13 min at 60 ° C. The stirring speed is 100 strokes / min
- Dilution: addition of 250 ml of cold hard water followed by 5 minutes of stirring
- 3 rinses of 5 min in the presence of 500 ml of cold hard water
- Water hardness (33 ° French: 330 mg CaCO₃ / l)
- Drying of the fabrics by two successive passes on a glazing machine photo
- Reflectance measurement: GARDNER photometer, Y filter, 4 fabric thicknesses.

FABRICS :

Cotton 405)
Polyester cotton (PE / C) 7406) Origin TESTFABRIC
Polyester "Dacron 54" (PE))

SOIL :

- KREFELD WFK (Alderstrasse, 44, Lieferschein)
- EMPA (COTTON Saint GALLEN EMPA, materials testing laboratory; Unterstrasse 11, PO Box, CH 9001, ST GALL).

APPARATUS :

Tergotometer (HOBOKEN, N, J, United state testing Co, Inc.) (2 pots per test)
- each pot of the tergotometer contains:
. 4 cotton test tubes (10 × 12 cm)
. 4 PE / C test pieces (10 × 12 cm)
. 4 polyester test pieces (10 × 12 cm)
. 4 KREFELD soiled cotton test tubes (10 × 12 cm) or:
4 KREFELD soiled cotton test tubes and
2 EMPA soiled cotton test tubes (10 × 12 cm)
. 500 ml of detergent solution (the detergent concentration is 6g / l.)
. Bath ratio 1/25

PERFORMANCE EVALUATION :

The reflectance measurement R _y is carried out using a GARDNER photometer filter y on 4 thicknesses of tissue. An additive is all the more effective as the reflectance of the fabric washed 5 times in its presence, according to the test described above, is important and approaches that of the clean fabric (R _y = 83%). The products tested are particularly active on synthetic fibers, as well as on a mixture of fibers. The reflectance measurements presented in the tables relate only to polyester fabrics.

TEST RESULTS :

We have studied the influence of the following parameters on the anti-depositing efficacy of products:
- the nature and the level of the acid,
- the rate of sulfonated polyester ,.
- hydrolysis of acetate functions.

In the tables below, the levels of the components vinyl acetate, crotonic acid or acrylic and sulfonated polyester are expressed in weight percentages. The performance of the best additives is compared to that of the commercial additive F4M (DOW CHEMICAL cellulose ether).

The weight composition of the detergent formula used is as follows:
Sodium alkybenzene sulfonate 7%
Sodium stearate 3%
Cémulsol® DB 6/18 2.5%
Cémulsol® LA 90 2.5%
Sodium tripolyphosphate 28.75%
Sodium pyrophosphate 2%
Sodium orthophosphate 0.5%
Sodium diisilicate 9.35%
Sodium sulfate 17.5%
Tinopal® SOP 0.2%
Tinopal® DMS X 0.2%
Esperase enzyme Novo 0.3%
Sodium perborate 25%
Magilex® 120 1%
0.2% sodium EDTA

EXAMPLE 1

Performance of different latexes of the first type:

The products listed in Table I are added in post-addition, the detergent concentration is 6 g / l, containing 0.42% of additive. Each tissue sample is washed 5 times in the presence of dirt.

The test referenced white corresponds to the five washes of fabrics in the presence of soiling and in the absence of additive.

EXAMPLE 2 :

Study according to the concentration in the detergent:

In accordance with Example 1, various tests are carried out by modifying the concentration of additive in the detergent bath.
- addition in post addition at different concentrations.
- detergent concentration 6g / 1.
- KREFELD soiling

EXAMPLE 3 :

Influence of soiling:
- addition of latex in post addition at constant concentration in the bath = 25 ppm.
- detergent concentration 6g / l
- KREFELD + EMPA soiling

With the mixture of soils, the cellulose ether amplifies the redeposition while the claimed additives remain effective.

EXAMPLE 4 :

Introduction of the additive 5 into a spray mixture ("slurry").

In a "slurry", the alkaline pH, the ionic strength and the high temperature tend to degrade the fragile products, therefore, the detergent obtained from a slurry containing the additive has been tested.

The usual ingredients of a detergent such as TPP, ionic surfactants, sodium silicate, sodium sulfate and water are mixed to form a slurry which constitutes "the slurry". This very alkaline mixture is then spray dried to obtain a powder. Non-ionic surfactants, bleaches, enzymes and perfumes are then added.

Two slurries have been prepared; additive 5 is added to one of the slurries. To simulate the hydration of TPP and the atomization, these mixtures are maintained for 1 hour 30 minutes at 90 ° C. with stirring. Under these pH and temperature conditions, the additive 5 is completely hydrolyzed; the vinyl acetate groups are transformed into vinyl alcohol. Three formulas having the same overall composition as above, see formula on page 7, were prepared from the slurries and tested under the experimental conditions identical to those described in Example 1.

The characteristics of the formulas prepared are as follows:
formula X: prepared from the control slurry without additives.
Y formula: prepared from the slurry control without additive, the additive ^No. 5 is introduced in post addition at 0.42% of the formula,
Z formula: prepared from the slurry containing 5 ^No. Additive, weight percent of additive ^No. 5 in the formula is 0.42%.

The values of the reflectances Ry of the dacron fabric obtained with these formulas are given in the following table IV:

The results obtained with the additive 5 introduced into a slurry are of the same order of magnitude as those obtained when this additive is introduced into the detergent bath. The product retains its anti-depositing properties when introduced into a slurry.

This example illustrates that after hydrolysis, the polymers of the invention retain their activity.

EXAMPLES 5 to 6

To measure the anti-fouling properties, the method used consists of washing tissue samples in the presence of the additive to be tested, depositing stains on these fabrics and rewashing them. The results obtained reflect the affinity of the textiles thus conditioned for soiling. The experimental conditions are as follows.

APPARATUS:

Linitest HANAU (2 pots per test) Each pot of linitest contains:

OPERATING CONDITIONS :

. Washing temperature: 60 ° C,
. Washing time: 40 mm (25 min rise in temperature and 15 mm at 60 ° C,
. Dilution: addition of 150 ml of cold hard water followed by 5 minutes of stirring,
. 3 rinses of 5 min in the presence of 400 ml of cold hard water,
. Water hardness (33 ° TH),
. Drying of the fabrics by two successive passes on a photo glazing machine,
. Reflectance measurement: GARDNER photometer, Y filter, 4 fabric thicknesses.

SOIL :

Car drain oil.

CONDUCT OF OPERATIONS :

. Packaging: a washing cycle is carried out in the presence of the additive to be tested. The additive can be introduced either into the detergent bath or during rinsing.
. Staining: using a burette, 4 drops of drain oil are placed in the center of the tissue sample placed on a "watch glass". The fabrics are then placed in an oven at 60 ° C for one hour. Half of the samples are thus soiled.
. Measurement of the reflectance of stained fabrics (GARDNER, filter Y).
. Washing: we operate in the same way as for packaging, but in the absence of additive. Each linitest jar thus contains two stained samples and two non-stained samples of each quality of fabric.
. Reflectance measurement after washing (GARDNER, filter Y). The reflectance of stained fabrics indicates the anti-fouling effect.

EXPRESSION OF RESULTS :

R_s: réflectance du tissu sali, avant lavage,
R₀: réflectance du tissu non sali, avant lavage,
R₁: réflectance du tissu sali, après lavage.The results concerning the removal of soiling are expressed in the form of the value of the "remission" R:

R _s : reflectance of soiled fabric, before washing,
R₀: reflectance of the soiled fabric, before washing,
R₁: reflectance of soiled fabric, after washing.

The higher the remission R, the greater the effectiveness of the additive as an anti-fouling agent.

EXAMPLE 5 :

This example illustrates the use of different latexes, the characteristics of which are given in Tables V and VI.

During the tests, the products are added to the medium at a pH such that they remain in the form of a suspension (addition on the third rinse), the solubilization of the latex only taking place during the following washing (where the pH increases).

The composition of the formula used is as follows:
TPP 21.5%
2% neutral pyrophosphate
0.5% anhydrous neutral trisodium phosphate
Silicate 3Na 8.6%
3.0N stearate 3.0%
TINOPAL DMSX® 0.2%
TINOPAL SOP® 0.2%
ESPERASE NOVO® 0.3%
Perborate (Air liquid) 25.0%
EDTA 0.2%
LABS neutral 7.0%
CEMULSOL 6 / 18® 2.5%
CEMULSOL LA 90® 2.5%
Na sulfate 24%

During each group of tests, the products tested (one to three) are compared to a test in the absence of an additive. The results obtained are given in the following table:

These results confirm the anti-fouling effect of the various alkali-soluble latexes tested.

EXAMPLE 6

This example illustrates the use of some alkali-soluble latexes at variable concentrations. The experimental conditions are the same as for Example 5. The results obtained are given in the following table.

These results confirm the anti-fouling effect of alkali-soluble latexes for several concentrations of additive.

EXAMPLE 7 :

The purpose of the test used during the examples which follow is to evaluate the anti-redepositing properties of a given additive.

The method used consists of washing tissue samples in the presence of the additive to be tested, and of dirt deposited on cotton wicks. The results obtained reflect the affinity of the textiles thus conditioned for soiling. The experimental conditions are as follows.

FABRICS :

APPARATUS :

Linitest HANAU (2 pots per test) (automated tergotometer)
Each Linitest jar contains:

OPERATING CONDITIONS :

. Washing temperature: 60 ° C,
. Washing time: 40 min (25 min rise in temperature and 15 min at 60 ° C,
. Dilution: addition of 150 ml of cold hard water followed by 5 minutes of stirring,
. 3 rinses of 5 min in the presence of 400 min of cold water,
. Water hardness: 33 ° TH,
. Drying of the fabrics by two successive passes on a photo glazing machine,
. Reflectance measurement: GARDNER photometer, Y filter, 4 fabric thicknesses.

SOIL :

"Spangler" (sebum + particles)

CONDUCT OF OPERATIONS:

- Conditioning: a washing cycle is carried out in the presence of the additive to be tested and of soiling impregnated on cotton wicks. The additive can be introduced either into the detergent bath or during rinsing.
- Measurement of the reflectance of stained fabrics (GARDNER, filter Y).
- Washing: the procedure is the same as for packaging, but in the absence of an additive. Each linitest jar thus contains two stained samples and two non-stained samples of each quality of fabric.
- Measurement of reflectance after washing (GARDNER filter Y). The reflectance of stained fabrics indicates the anti-fouling effect.

EXPRESSION OF RESULTS :

R₂: réflectance du tissu, sali après lavage,
R₀: réflectance du tissu, avant lavage,
R₁: réflectance du tissu blanc non lavé.

Plus la rémission delta R est faible, plus est grande l'efficacité de l'additif comme agent anti-redéposition.The results concerning the anti-redeposition of soiling are expressed in the form of the value of the difference delta R of reflectance before and after washing and of the efficiency E
Delta R: R₀ - R₂:

R₂: reflectance of the fabric, soiled after washing,
R₀: reflectance of the fabric, before washing,
R₁: reflectance of unwashed white fabric.

The lower the delta R remission, the greater the effectiveness of the additive as an anti-redeposition agent.

The purpose of this example is to demonstrate the anti-redepositing effect of an alkali-soluble latex in the presence of a formula in which the builder or the washing aid consists of tripolyphosphate (TPP) and zeolite 4A .

The composition of the formula used is as follows:
TPP 19.0%
Zeolite 17.0%
9.5% Na sulfate
Neutral pyrophosphate 2.0%
Anhydrous Na₃PO₄ 0.5%
Silicate 3Na 8.6%
BLANOSE BWS 1.5%
TINOPAL DMSX® 0.2%
TINOPAL SOP® 0.2%
ESPERASE NOVO® 0.3%
Perborate 25.0%
Na 3.0 stearate
LABS 7.0
CEMULSOL 6 / 18® 2.5%
CEMULSOL LA 90® 2.5%
EDTA 0.2%
H₂O 1.0%

This example illustrates the use of different latexes at a concentration of 100 ppm in a detergent formula having a concentration of 6 g / l of bath.

Claims (16)

1 - Antifouling and antiredepositive latex usable in the aqueous washing of textile materials, consisting of vinyl copolymers characterized in that they consist either of acetate copolymers of unsaturated vinyl carboxylic acids optionally grafted with sulfonic polyesters or of (meth) acrylic copolymers grafted with sulfonic polyesters. 2 - Latex according to claim 1 consisting of vinyl acetate-carboxylic acid copolymers characterized in that the carboxylic acid is chosen from maleic, crotonic, (meth) acrylic or itaconic acids. 3 - Latex according to claim 1 and claim 2 characterized in that the acid content varies between 3 and 8%. 4 - Latex according to claim 1 and claim 3 characterized in that the latexes consisting of vinyl acetate-carboxylic acid copolymers are grafted with at most 10% polyestersulfonate. 5 - Latex according to claim 1 characterized in that the polyestersulfonate contains 60% phthalic or succinic acid for 40% ethylene oxide. 6 - Latex according to claims 1 to 5 characterized in that they contain by weight
- from 84 to 96% vinyl acetate,
- from 3 to 6% of crotonic or acrylic acid or one of its derivatives,
- 1 to 10% of sulfonated polyester. 7 - Latex according to claim 6, characterized in that it contains:
- from 87 to 94% vinyl acetate,
- from 4 to 5% of crotonic or acrylic acid,
- 2 to 8% of sulfonated polyester. 8 - Latex according to claim 7, characterized in that the acid is acrylic acid. 9 - Latex according to claims 6 to 8, characterized in that one saponifies all or only part of the acetate functions. 10 - Latex according to claim 1 consisting of (meth) acrylic esters and carboxylic acids chosen from (meth) acrylic, itaconic and maleic acids. 11 - Latex according to claim 10 characterized in that the (meth) acrylic esters are esters in which the alkyl chain contains 1 to 4 carbon atoms. 12 - Latex according to claim 10 characterized in that the (meth) acrylic esters are chosen from methyl (meth) acrylate and ethyl (meth) acrylate. 13 - Latex according to claims 10 to 12 characterized in that they are grafted with at most 10% polyestersulfonate. 14 - Latex according to claim 13 characterized in that the polyestersulfonate contains 60% of phthalyl or succinyl groups for 40% of ethylene oxide groups. 15 - Detergent compositions characterized in that they contain at least 0.1% by weight of latex according to claims 1 to 14. 16 - Detergent compositions characterized in that they contain at least 0.2% and preferably at least 0.4% of latex according to claim 6.