ES2249571T3 - METHOD FOR SOFTENING FABRICS. - Google Patents

Abstract

Fabric softening compositions comprise 3-20 wt. % a cationic fabric softener, 1-10 wt. % a fabric co-softener and at least 1 wt. % a hydrotrope. They are of medium viscosity, transparent and free from organic solvents and show good softening performance.

Description

Method to soften tissues.

The present invention relates to compositions fabric softeners, preferably conditioners translucent, clear or transparent, which in addition to a fabric softener cationic tissues comprise a co-softener of tissues and a hydrotrope.

Fabric softener compositions are known in the art for providing benefits such as softness and / or antistatic properties to the treated tissue. Without However, today, consumer acceptance of fabric softening compositions are determined not only by the results achieved with these products but also by the aesthetics associated with them. The viscosity of the product is therefore both an important aspect in a successful formulation of such commercial products, and medium to low grade viscosities Stables are highly preferred by consumers.

To realize this need, they have been incorporated fatty acids to fabric softener compositions. These descriptions can be found in the pending application of European patent document EP 95870104.7.

Fabric softeners are usually achieved transparent with the use of high concentrations of solvents organic Viscous solutions are usually prepared with the addition of a gelling agent / thickener. However we have discovered that certain compositions can occur transparent without the use of organic solvents, without the need for add a thickener / gelling system. The reduction or elimination of a thickener / gelling system will reduce the cost of formulation. In addition the organic solvents used to produce soothing compositions of transparent fabrics have bad odor.

According to this, it is an object of the invention provide a medium viscosity softening composition, capable to provide benefits of softness to the tissues, control static, water dispersibility, rewetting and an aroma nice. It is a further aspect of the invention that preferably, the softening composition is transparent.

Smoothing compositions of transparent fabrics which contain high levels of organic solvents are fine known in the art as described in the documents of International Patent WO 96/19552 or WO 01/02522 or WO 96/09365 or the US patent document US 5656585 or the document of WO 99/09122 international patent or patent document United States US 5747443.

A person versed in the technique can produce soothing compositions of transparent fabrics with the combination of quaternary ammonium compounds with organic solvents. These compositions generally have high concentrations of organic solvents that are necessary to provide the transparency, but they have a very bad smell and usually results Bad as softeners.

In addition these compositions have a viscosity low in the absence of a thickening / gelling system.

Acute viscous cleaning compositions that include: a) an inorganic or organic acid, b) a detergent cationic, c) a water insoluble covalent compound or partially soluble such as an ester of an inorganic acid, a fatty acid or an ester of a fatty acid, an ester of an acid carboxylic or an amine oxide and d) an anionic sulphonate, is described in the patent documents of Great Britain GB 1240469 or European patent document EP 0 265 979.

Single phase transparent fabric softeners comprising an anionic surfactant having an alkyl radical containing at least eight carbon atoms, a surfactant cationic and an effective amount of propylene glycol and a salt of alkali metal of benzene, toluene or xylene sulfonate se described in the US patent document US 4751009.

The present invention is based on the surprising discovery that it is possible to obtain a fabric softener stable, transparent, medium viscosity that gives good results to soften the tissues, which comprises a cationic surfactant, a co-softening agent and a hydrotrope, such as an alkali metal salt of benzene sulphonate, cumene, toluene or xylene.

Average viscosity means a viscosity from 50 mPa.s to 5,000 mPa.s, preferably 200 to 2,000 mPa.s, as it is measured in a Brookfield LV, spindle 2, 12 rpm and at 20 ° C.

The results of these softening compositions of fabrics are not compromised by their highest viscosity, they are highly dispersible in water without the usual hydration gelling agent that can occur with some viscous systems of surfactants Smoothness results are as good as, if not  better than those of traditional systems.

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The present invention is a method for treating tissues comprising the step of contacting said tissue in the rinse cycle of a fabric washing machine with a medium aqueous containing a composition comprising:

a) a cationic fabric softener in a amount from 3% to 20% by weight

b) 1% to 10% by weight of a compound fabric co-softener of formula (II) as define below

c) 0.1% to 5% by weight of a hydrotrope; preferably 0.1% to 2.5% by weight.

Cationic fabric softener

A cationic fabric softener is a essential ingredient of the invention. Typical concentrations of cationic fabric softener in the softener compositions are 3% to 20% by weight, preferably 4% to 15% by weight, and more preferably 4% to 10% by weight of the composition.

The preferred softener components of cationic tissues include ammonium fabric softeners water dispersible quaternary or a precursor amine of same. Preferred quaternary ammonium compounds here are from formula (I):

one

where Q is selected from -CH_ {2} -, -O-C (O) -, -C- (O) -O-, and -O-C (O) -O- (preferably -CH2 -);

R 1, R 2 and R 3 are selected independently of C 1 -C 4 alkyl or C 1 -C 4 hydroxyalkyl or H (typically methyl);

T1 is alkyl or alkenyl C 6 -C 22 (typically alkyl);

n is an integer from 0 to 4 (preferably n is 2); Y

X - is an anion compatible with the softener.

Non-limiting examples of a compatible anion with the softener include chloride or methylsulfate, preferably chloride.

The alkyl or alkenyl T 1 chain should contain at least 5 carbon atoms, preferably at least 13 carbon atoms, more preferably at least 15 atoms of carbon. The chain can be linear or branched.

A specific example of an ammonium compound quaternary suitable for use in aqueous compositions of fabric softener present is tallow trimethylammonium hydrogenated X - where X - is preferably chloride.

The unsaturation level of the chain can measured by the value of iodine (IV) of the corresponding fatty acid, which in the present case should preferably be in the range of 5 to 100 distinguishing two categories of compounds, depending on whether they have an IV below or above 25.

The anion is present simply as a counterion of charged quaternary ammonium compounds positively The nature of the counterion is not critical in the practice of the present invention. The scope of this invention does not It is considered limited to no particular anion.

By "amine precursor thereof" is understands the secondary or tertiary amine that corresponds to the above quaternary ammonium compounds, said amines are substantially protonated in the present compositions due to pH values.

In the softening agents of previous tissues, especially in biodegradable tissue softening agents, The pH of the liquid compositions included here is a parameter Preferred of the present invention. In fact, the pH influences the stability of quaternary ammonium compounds or precursors amines, especially during storage conditions prolonged The pH as defined in the current context, is measured in undiluted compositions at 20 ° C. For stability Optimum hydrolytic of these compositions, undiluted pH, measured under the conditions mentioned above, it is ideally in the range of 2 to 5. The pH of these compositions described here It can be regulated with the addiction of a Bronsted acid.

Examples of suitable acids include acids inorganic minerals, carboxylic acids, in particular acids low molecular weight carboxylic (C 1 -C 5), and alkylsulfonic acids. Acids Suitable inorganic agents include HCl, H 2 SO 4, HNO 3, and H_ {3} PO_ {4}. Suitable organic acids include acid formic, acetic, citric, methylsulfonic and ethylsulfonic. Acids Preferred are citric, hydrochloric, phosphoric, formic acid, methylsulfonic, and benzoic. Especially preferred is acid citric.

The softening compositions of the invention They will also understand a liquid vehicle. Liquid vehicles Suitable are selected from water, organic solvents and mixtures thereof. The liquid vehicle used in the compositions ready to use is preferably at least mainly water Due to its low cost, safety, and environmental compatibility. The concentration of water in the liquid is preferably at least 80%, more preferably at least 90%, by weight of the vehicle. Preferably the liquid vehicle is at least 20%, the most preferably at least 30% by weight of the composition. Can be used mixtures of water and organic solvents of low molecular weight (for "low molecular weight" means less than 200). Solvents Preferred organic low molecular weight are; alcohols monohydric, such as ethanol, propanol, isopropanol or butanol; dihydric alcohols, such as glycol; trihydric alcohols, such as glycerol, and polyhydric alcohols (polyols).

Hydrotropes

Hydrotropes help solubility or dispersibility of the different surfactants in aqueous solution. This usually has the side effect of reducing the viscosity of the resulting mixture. Surprisingly, we have discovered that the use of a hydrotrope in our compositions It causes an increase in viscosity. While we are not linked to any theory we believe this is probably due to the complex formed between the anionic salt of the hydrotrope and the cationic surfactant. The complex is transparent and soluble in solution and provides a higher viscosity matrix.

Examples of suitable and preferred hydrotropes are the alkali metal salts of a benzene sulphonate, cumene, toluene and xylene, ideally sodium salt.

Fabric co-softeners

It is understood as co-softener of woven by the person versed in the hydrophilic compounds technique non-quaternaries that are added to improve the results of the softener.

The co-softeners used are amines of formula (II)

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2

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at least one, and preferably not more than two of R 3, R 4 and R 5 are alkyl or alkenyl C 16-22, (preferably alkenyl), preferably C 17-19 ideally C 18; Y the remaining group (s), if any, are C 1-4 hydroxyalkyl or hydrogen, preferably C 1-4 hydroxyalkyl, ideally hydroxyethyl. A preferred compound is oleylbis (2-hydroxyethyl) amine.

Other co-softeners include, but they are not limited to; amine oxides, betaines, and soaps of alkali metals Preferred Fatty Acid Precursors they contain a high proportion of unsaturation, the oleyl groups are the most preferred

Optional

The composition may also contain components options that may be suitable to further improve the aesthetic appearance of the tissues treated in this way. Suitable optional components include polyethylene glycols, additional fabric softening components, enzymes, complexes of cyclodextrins / aromas and aroma free release systems, and  mixtures thereof, preferably in the form of a metal salt alkaline, ideally sodium.

Polyethylene glycol

A polymeric material that can optionally Included is polyethylene glycol (PEG). When using PEG you can provide an increase in viscosity stability in the Composition of the invention during storage. The weight Typical molecular is for these purposes in the range of 500 to 100,000, preferably 1,000 to 50,000, more preferably of 1,500 to 10,000. A more preferred molecular weight is 4,000. When are present, typical concentrations of polyethylene glycols go from 0.01 to 1% by weight, preferably from 0.05% to 0.5% by weight of the composition.

Additional components

The composition can also optionally contain additional components, examples include, but not are limited to, helps the concentration of surfactants, helps to the concentration of electrolytes, antioxidant agents and reducers, emulsifiers, bactericides, dyes, perfumes, preservatives, optical brighteners, anti-ionizing agents, chelants, natural and synthetic extracts and agents defoamers

Stabilizers

They can also optionally be added stabilizers When used, these stabilizers will help achieve the desired viscosity in the final product as well as stabilize the final product during storage. The stabilizers are typically selected from surfactants single long chain alkyl cationics, non-surfactants alkoxylated ionic, amine oxides, fatty acids, and mixtures of the same, and are typically used in a concentration of 0 to 15% by weight of the composition.

Electrolyte stabilizers

Inorganic viscosity control agents which can also act as such or increase the effect of stabilizers, include water soluble, ionizable salts that they can also optionally be incorporated into Compositions of the present invention. The incorporation of these compounds to the composition must be performed at a very high speed low.

A wide variety of salts can be used. ionizable. Examples of suitable salts are metal halides of groups IA and IIA of the Periodic System of the Elements, by example, calcium chloride, magnesium chloride, sodium chloride, potassium bromide, and lithium chloride. Ionizable salts are particularly useful during the process of mixing the ingredients to make the compositions, and later get the desired viscosity The amount of ionizable salts used depends of the amount of active ingredients used in the compositions and can be adjusted according to the wishes of the formulator. The typical concentrations of salts used to control viscosity of the composition are 20 to 2,000 parts per million (ppm), preferably from 20 to 1,100 ppm, by weight of the composition.

Polyamonic alkylene salts can incorporated into the composition to provide control of viscosity in addition to, or instead of, ionizable salts water soluble above. In addition, these agents can act as sequestrants, forming ion pairs with detergents anionics dragged there from the main wash, in the lightened, and in tissues, and can improve softness. These agents can stabilize viscosity over a wide range of temperatures, especially at low temperatures, compared to inorganic electrolytes.

Specific examples of polyamonic salts of alkylene include l-lysine monohydrochloride and 1,5-diamonium dihydrochloride 2-methylpentane The present invention also includes a method of treating tissues comprising the stage of contacting said tissues in the rinse cycle with a aqueous medium containing a composition as defined herein previously. Preferably, the aqueous medium is at a temperature between 2 to 40 ° C, preferably between 5 to 25 ° C.

The invention is illustrated in examples no. following limitations, in which all percentages are in based on the percentage of active weight unless otherwise stated way.

Softness improvement

The use of a cationic surfactant of the formula (I) usually confers relatively poor execution compared with standard esterquat design.

We have checked the performance as softener of formulations with monoalkyl cationic agents, comparing with a standard, the fabric softener composition commercially available based on the esterquat design.

Curl fabrics were washed with different fabric softeners, then, once dried, were judged by A group of selected people.

The group of selected people was asked to assign a number from 0 (very rough) to 7 (very soft) for test samples.

Products tested and results:

Active matter Product A Product B Product C Softener commercial Monoalkyl cationic (alkyl chloride trimethylammonium) 3% 3% 3% / Cocoamidopropyl betaine 3% / / / Alkyl oxide dimethylamine / 2.1% / / Oleilbis (2-hydroxyethyl) amine / / 1.85% / Disebo of esterquat / / / 5.4% Dose / wash 68 ml 68 ml 68 ml 84 ml Cationic / Wash 2.04 ml 2.04 ml 2.04 ml 4,536 Punctuation half 2.5 3.1 4.2 4.8

As is fully apparent, 1.85% of a amine tissue co-softener of formula (II) greatly increases the performance as a fabric softener softener of monoalkyl cationic tissues.

Viscosity improvement

Increase the viscosity of the formulation, and, when at the same time, maintaining product transparency is very hard.

The following tables list the thickeners evaluated:

Thickeners % Viscosity disadvantages Cps Brookfield LVT Rohagit KF720-cationic polyelectrolyte based in 0.5 125 Hard to dissolve methacrylamide (RTM) Rohagit KL280 - acrylic polymer (RTM) 0.5 10 yellow 2.5 42 orange Acusol 882 - modified polyethylene glycol (RTM) 0.5 2 2.5 4,5 Acusol 884 - modified starch (RTM) 0.5 10 opaque Xanthan gum (various P.m) 0.02 / insoluble 0.5 / Cocoamidopropyl betaine 1.2 24 PVP - Polyvinyl pyrrolidone one 3 yellow Poliflos SA 4W - hidroxialquil poligalactomanán (RTM) 0.3 115 Difficult to dissolve Poligel K100 - cationic polymer (RTM) 0.5 fifteen opaque

There are two polymers that give higher viscosities: Rohagit KF720 and Poliflos SA 4W. Unfortunately, they have the disadvantage of being very expensive and difficult to dissolve in formulations

We have discovered that the addition of a hydrotrope, such as sodium cumene sulphonate (SCS) and the Sodium xylene sulphonate (SXS), can be used as thickeners: sodium cumene sulphonate (40% active) at a concentration of 2% increases the viscosity of the formulation from 10 cps to 500-700 cps.

Materials of departure Reference Sample Sample Sample Sample one 2 3 4 Alkyl chloride trimethylammonium- 6 6 6 6 6 fifty% of active Fragrance 0.95 0.95 0.95 0.95 0.95 Eltesol SCS- (Sulfonate cumene / one 1.5 2 / sodium 40%) (RTM) Eltesol SXS- (Sulfonate xylene / / / / 2 sodium 40%) (RTM) Water rest rest rest rest rest Viscosity (LVT1) 6 rpm fifteen 18 12 500 200 Appearance Transparent Transparent Transparent Transparent Transparent

Additional examples include:

Name registered Description of the Sample Sample Sample material of departure 5 6 7 Alkyl trimethylammonium chloride - 50% of active Active softener 6 6 6 Ethomeen S / 12 (Diolelamine) (RTM) Co-softener 1.8 1.8 1.8 Eltesol SC40 (Sodium Cumene Sulfonate - 40% Hydrotrope 2 2.5 3.0 from active) (RTM) Fragrance Fragrance 0.95 0.95 0.95 Citric acid Adjuster pH 0.6 0.6 0.6 Preservative BIT Preservative 0.05 0.05 0.05 Excerpts natural 0.025 0.025 0.025 Water rest rest rest Viscosity (LVT1) 6 rpm 600 cps 700 300 Appearance transparent transparent opaque

As can be seen, the increase in concentration of hydrotrope above 2.5% causes a decrease in viscosity and opacity, both undesirable characteristics of the present invention.

Claims (8)

1. A method of treating tissues comprising the step of contacting the tissue in the rinse cycle of a tissue washing machine with an aqueous medium containing a composition comprising:

to)

a cationic fabric softener in an amount of 3% to 20% in weight,

b)

of the 1% to 10% by weight of a co-softening compound of tissues of formula (II)

2 at least one, and preferably not more than two, of R 3, R 4 and R 5 are alkyl C 16-22 or alkenyl (preferably alkenyl), preferably C 17-19 ideally C 18; Y the remaining group (s), if any, are C 1-4 hydroxyalkyl or hydrogen, preferably C 1-4 hydroxyalkyl, ideally hydroxyethyl.

C)

0.1% at 5% by weight of the hydrotrope.

2. A method according to claim 1, wherein the cationic fabric softener is 4% to 10% by weight of the composition. 3. A method according to claim 1 or 2, in where cationic fabric softeners are composed of quaternary ammonium having the formula (I), below: one where Q is selected from -CH_ {2} -, -O-C (O) -, -C- (O) -O-, and -O-C (O) -O- (preferably -CH2 -); R 1, R 2 and R 3 are selected independently of C 1 -C 4 alkyl or C 1 -C 4 hydroxyalkyl or H (preferably methyl); T1 is alkyl or alkenyl C 6 -C 22 (preferably alkyl); n is an integer from 0 to 4 (preferably n is 2); Y X - is an anion compatible with the softener. 4. A method according to claim 3, wherein the X - anion compatible with the softener is chloride or methylsulfate, preferably chloride. 5. A method according to claims 3 and 4, where the alkyl or alkenyl T 1 chain should contain the minus 5 carbon atoms, preferably at least 13 atoms of carbon, more preferably at least 15 carbon atoms. 6. A method according to any one of the claims 1 to 5, wherein the hydrotrope is a sulphonate of benzene, cumene sulphonate, toluene sulphonate or sulphonate xylene, in the form of an alkali metal salt, ideally sodium. 7. A method according to any one of the claims 1 to 6, wherein the hydrotrope is at a concentration from 0.1 to 2.5% w / v. 8. A method according to claim 7, wherein the fabric co-softener is the oleylbis (2-hydroxyethyl) amine.