RU2130522C1 - Fabric-softening composition - Google Patents

Abstract

FIELD: textile industry. SUBSTANCE: composition contains: (i) water-insoluble fabric-softening compound with two C_8-28-alkyl or alkenyl groups bound to head quaternary ammonium group through at least one ester linkage or quaternary ammonium compound containing one chain having in average at least 20 carbon atoms and (ii) solubilizing means including amphoteric surfactant. Weight ratio of the two components is more than 1:6. When diluted with water to 5 wt %, at least 70% of fabric-softening compound is present in water. EFFECT: essentially increased stability and also distributive and dispersive properties. 9 cl, 7 tbl

Description

Technical field
The invention relates to compositions for softening tissues. The present invention, in particular, relates to compositions for softening tissues, which have excellent stability, excellent distribution and dispersion properties.

BACKGROUND OF THE INVENTION
Well-known compositions containing fabric softener are added which are added by rinsing. Typically, such compositions contain a water-insoluble fabric softener dispersed in water at a softener level of up to 7% by weight, in which case the compositions are considered diluted, or at a softener level of 7% to 30% by weight, in which case the compositions are considered concentrates. Fabrics can also be softened by using sheets coated with a softener, which is used in drum dryers. In more detail, commercially available fabric softeners typically form stacked layered structures in water that have characteristic transition temperatures of the L _β phase to the L _α phase.

 Fabric softener compositions known in the art, rinsing, soften the fabric by depositing dispersed colloidal softener particles on them, while the sheets used in dryers soften the fabric by direct transfer of the molten softener, as described in P.G. Laughlin "Surfactans Science Series 2 volume 37. Cationic surfactans, Physical Properties, Pages 449 to 465 (Marcel Decker, inc 1991).

 Conventional liquid tissue softening compositions are in the form of dispersed colloidal particles of a tissue softening compound. Tissue softening compositions are also described, comprising a dissolved tissue softening compound in an organic solvent, and powder or granular compositions.

 Tissue softening compositions formed from dispersed colloidal particles have complex, unstable structures. Due to such instability, there are many problems associated with conventional tissue softening compositions. The main problems are: physical instability when they are stored at high and low temperatures; when frozen, they irreversibly turn into gels; it is difficult to obtain compositions that show good dispersibility in the washing liquid, good deposition on the fabric and good distributability from the metering device of the washing machine.

 Poor dispersibility leads to uneven coating of the fabric softener on the laundry, and in some cases stains may occur. These problems are exacerbated by the use of concentrated tissue softening compositions and by the addition of fragrances.

 Physical instability can lead to thickening of the composition during storage to a level where the composition cannot be poured, and even to irreversible gel formation. Gel formation can also occur in the metering device of the washing machine when the temperature rises with the influx of warm water. Thickening is very undesirable because the composition can no longer be used in a conventional manner. Physical instability can also lead to phase separation into two or more separate layers.

 For the consumer, however, concentrated products, good dispersibility and storage stability at high or low temperatures are desirable.

 The problems associated with traditional dispersed colloidal particles can be attributed to the methods of the prior art.

 In US patent N 4789491 (Chang) (Chang) presents a specific method for producing aqueous dispersions of cationic emollients. The method is aimed at overcoming the disadvantages associated with the viscosity of the product, poor distribution and dispersibility during storage.

 EP 0239910 (Procter and Gamble) provides compositions containing dispersions of either diester or monoester quaternary ammonium compounds in which nitrogen has either two or three methyl groups stabilized by maintaining a low pH.

The physical stability of the fabric softener compositions added by rinsing is enhanced by the addition of viscosity adjusting agents or anti-gel agents. For example, in EP 13780 (Procter and Gamble) (Procter & Gamble) viscosity adjusting agents are added to certain concentrated compositions. These substances may include C ₁₀ -C ₁₈ fatty alcohols. More recently, in EP 280550 (Unilever) (Unilever), it was proposed to increase the physical stability of diluted compositions containing biodegradable quaternary ammonium compounds and fatty acid by adding nonionic surfactants. EP 507478 (Unilever) (Unilever) provides a physically stable tissue softening composition containing water-insoluble biodegradable ester-linked, quaternary ammonium compounds and a nonionic stabilizer.

 Various suggestions have been made regarding the supply of fabric softener in granular or powder form. Typical is the proposal presented in EP 111074, in which silica is used to deliver the emollient. The disadvantage of using a carrier such as silicon dioxide is that it increases the volume of the product and does not fulfill its function, as it makes the powder compatible with other ingredients that may be contained in the washing powder.

 EP 569184 (Unilever) (Unilever) describes the use of a granular composition, which is diluted and then added to the metering device of the washing machine.

 WO 92/18593 (Procter and Gamble) provides a granular tissue softener composition that can be added to water to form an aqueous emulsion. The composition comprises a nonionic fabric softener, for example a sorbitan ester and an alkyl cationic surfactant with a chain of the same length.

 WO 93/23510 (Procter and Gamble) provides liquid and solid fabric softeners, including biodegradable tissue softener compounds, complex diester quaternary ammonium compounds, and a viscosity and / or dispersant modifier, and specific methods are also provided in the application. receiving such products. The viscosity and / or dispersibility modifier may be an alkyl cationic or nonionic substance with a single chain length. The solid composition when added to water forms an emulsion or dispersion.

 Our pending application GB 9323268.4 describes the use of tegobetaine to eliminate the problems associated with the instability caused by the use of perfumes in concentrated fabric softeners.

 In an attempt to overcome the problems associated with dispersed colloidal particles, the methods of the prior art turned to fabric conditioners in the form of solutions of compounds to soften tissue in organic solvents. Examples of compositions of this type are presented in our pending application GB 9301811.7. However, when in contact with water, dispersed colloidal particles are still formed.

 Another way to obtain fabric softener solutions is through the use of specific structural modifications.

 US Pat. No. 3,892,669 (Lever Brothers, CL 252 8 D 06, 1975) describes a transparent homogeneous aqueous tissue softener composition that is limited to solubilized tetraalkyl quaternary ammonium salts having two short chain alkyl groups and two long chain alkyl groups, with longer chain have methyl and ethyl branching. Solubilizers include arylsulfonates, diols, ethers, low molecular weight quaternized compounds, sulfobetaines, and nonionic surfactants. In the description, it is noted that nonionic surfactants and phosphine oxides are unsuitable for independent use and can find application only as auxiliary solubilizers.

 It was found that a new composition for softening tissues can be formed without the disadvantages inherent in the compositions of the previous field. The present invention provides tissue softening compositions having excellent emollient properties, which furthermore exhibit excellent storage stability at both high and low temperatures, good thawing recovery after freezing, and excellent distributability and dispersibility when the composition is concentrated , and even when the compound for softening the tissue is concentrated to levels above 30 wt.%. In addition, the compositions obtained in accordance with our invention, characterized by the absence of loss of emollient ability.

Definition of invention
In accordance with one aspect of the invention, there is provided a fabric softening composition comprising:
(i) a substantially water-insoluble tissue softener compound comprising a compound having two C ₁₂ -C ₂₂ alkyl or alkenyl groups linked to a quaternary ammonium head group through at least one ester linkage, or a quaternary ammonium compound containing one chain with average chain length equal to or greater than C ₂₀ , and
(ii) a solubilizing agent comprising an amphoteric surfactant and optionally non-surface active co-solubilizer, characterized in that when the fabric softening composition is diluted with water to a concentration of 5% relative to (i) and (ii) at least 70% by weight of a tissue softening compound is in solution.

 In yet another aspect, the invention provides for use as a tissue softening composition of self-limiting molecular aggregates (as defined below).

DETAILED DESCRIPTION OF THE INVENTION
Applicants believe that the fabric conditioner of the invention is not in its usual layered form and upon contact with water can be partially solubilized in the form of self-limiting molecular aggregates, for example, in the form of micelles or micellar solutions with solid or liquid internal content or as mixtures thereof. When the composition is in a form containing water, the composition itself may be at least partially in the form of self-limiting molecular aggregates. We believe that they present new structures for tissue softening compositions that overcome problems in the prior art.

 The tissue softening compound and the solubilizing agent form a translucent (translucent) mixture. To accurately determine whether or not a composition is within the scope of the present invention, the following tests can be used.

Test 1
(a) The fabric softening composition was diluted with water to a concentration of 5% by weight (relative to the fabric softening compound and the total amount of solubilizing agent, i.e., nonionic surfactant and surfactant co-solubilizer). The diluted composition was heated to a temperature between 60 - 80 ^° C, then cooled to room temperature and stirred for 1 hour to form an equilibrium. The first portion of the obtained test liquid was taken, and the material, which was insoluble in the aqueous phase, was separated by segmentation or filtration until a transparent aqueous layer was formed. (For this purpose, ultracentrifuges or ultrafilters can be used). Filtration can be carried out by passing through successively installed film filters with a thickness of 1, 0.45 and 0.2 microns.

 (b) The concentration of the tissue softening compound in the transparent layer was measured by titration with a standard anionic surfactant (sodium dodecyl sulfate) using a dimidium sulfide disulfine blue indicator with two-phase titration with chloroform as an extraction solvent.

 (c) Titration with an anionic surfactant was repeated with a second portion of the tissue softening composition, which was diluted but not separated.

 (d) Comparison of (b) and (c) showed that the concentration of the tissue softening compound in (b) is at least 70 wt.% (preferably 80 wt.%) relative to the concentration of the tissue softening compound in (c). This indicates that the fabric softening compound was in solution.

Test II
(a) The fabric softener composition was diluted as for Test 1.

(b) The viscosity of the diluted composition was measured at a shear rate of 110 sec ^-1 .

(c) The diluted composition was heated to 60 ^° C. and held at this temperature for one day.

(d) The diluted composition was cooled to 20 ^° C. and the viscosity was again measured at a shear rate of 110 sec ⁻¹ .

 (e) A comparison of the viscosities of (b) and (c) showed that they differ by less than 5 mPa (millipoise).

Preferably, the fabric softener composition of the invention meets the following test:
Test III
(a) The fabric softener composition was diluted as for Test 1.

(b) The viscosity of the diluted composition was measured at a shear rate of 110 sec ^-1 .

 (c) The diluted composition was frozen and thawed.

(d) Again measured the viscosity at a shear rate of 110 sec ^-1 .

 (e) A comparison of the viscosities of (b) and (c) showed that they differ by less than 10 mPa (millipoise).

 Fabric softener compositions of the invention may be translucent. "Translucent" in the context of this invention means that when a cell 1 cm deep is filled with a fabric softening composition, an agent with 12 advantages can be read through the cell on the front side.

 Another advantage of the present invention is the enhancement of the softening effect of the composition compared to the compositions of the preceding area containing detailed levels of the fabric softening compound.

 The present invention also has the advantage that high perfume levels can be tolerated without adversely affecting the stability of the product.

 Compound for softening tissues.

The tissue softening compound is suitably a water-insoluble quaternary ammonium compound comprising one alkyl or alkenyl chain of a length equal to or greater than C ₂₀ , or more preferably, the softening compound includes a polar head group and two alkyl or alkenyl chains, each of which is of medium length chains equal to or greater than C ₁₂ , for example, a quaternary ammonium compound having two C _12-22 alkyl or alkenyl groups linked to a quaternary ammonium head group through n at least one ester linkage.

Preferably, the tissue softening compound of the invention has two long chain alkyl or alkenyl chains with an average chain length of equal to or greater than C ₁₄ . More preferably, each chain has an average chain length equal to or greater than C ₁₆ . Most preferably, at least 50% of each long chain alkyl or alkenyl group has a C ₁₈ chain.

 Preferably, the long chain alkyl or alkenyl groups of the tissue softening compound are predominantly linear.

The tissue softening compounds used in the compositions of the invention have molecules that provide excellent softening and are characterized by a phase transition temperature L _β and L _α corresponding to more than 25 ^° C, preferably more than 35 ^° C, most preferably more than 45 ^° C The phase transition temperature of L _β to L _α can be changed by DSC (differential scanning calorimetry), as described in "Handbook of Lipid Bilayers, L. March, CRC Press, Boca Raton Florida 1990 (Pages 137 and 337)."

Essentially insoluble tissue softening compounds in the context of this invention are defined as tissue softening compounds having a solubility of less than 1 • 10 ^-3 wt.% In demineralized water at 20 ^° C. Preferably, the tissue softening compound has a solubility of less than 1 • 10 ^-4 . Most preferably, tissue softening compounds have a solubility at 20 ^° C. in demineralized water of 1 · 10 ^-8 to 1 · 10 ^-6 .

 Preferred tissue softening compounds are quaternary ammonium compounds.

в которой каждую R¹ группу независимо выбирают из C_1-4 алкильных, гидроксиалкильных или C_2-4 алкенильных групп, и в которой каждую R² группу независимо выбирают из C_8-28 алкильных или алкенильных групп
T является

и
n представляет целое число в диапазоне 0 - 5.It is particularly preferred if the tissue softening compound is a water-insoluble quaternary ammonium compound that includes a compound having two C _12-18 alkyl or alkenyl groups linked to the molecule via at least one ester linkage. More preferably, the quaternary ammonium compound has two ester bonds. An especially preferred quaternary ammonium compound having an ester bond for use in the invention can be represented by the formula:

in which each R ¹ group is independently selected from C _1-4 alkyl, hydroxyalkyl or C _2-4 alkenyl groups, and in which each R ² group is independently selected from C _8-28 alkyl or alkenyl groups
T is

and
n represents an integer in the range 0 - 5.

 Particularly preferred is di (thalloyloxyethyl) dimethyl ammonium chloride, available from Hoechst (Houst).

в которой R¹, n и R² являются такими, как они определены выше.A second preferred type of quaternary ammonium compound may be represented by the formula:

in which R ¹ , n and R ² are as defined above.

 To protect the environment, it is beneficial that the quaternary ammonium compound is biodegradable.

 Preferred materials of this class, for example, 1,2 bis (reflected thalloyloxy) -3-trimethylammonium propane chloride, and a process for their preparation are described, for example, in US Pat. No. 4,137,180 (Lever Brothers) (Levar Brazez). These materials preferably include a small amount of the corresponding monoester as described in US Pat. No. 4,137,180, for example 1-reflected thalloyloxy-2-hydroxy-3-trimethylammonium propane chloride.

Amphoteric solubilizer
The solubilizing agent is an amphoteric surfactant and is characterized in terms of phase behavior. Suitable solubilizing agents are amphoteric surfactants in which, upon contact with water, the first formed lyotropic liquid crystalline phase is ordinary cubic (I1) or ordinary cubic / bicontinuous (V1) or hexagonal (H1), or nematic (Ne1) or intermediate ( Int1) a phase as defined in GIT Tiddy et al., J. Chem. Soc. Faraday Trans. 1., 79, 975, 1983 and GIT Tiddy, "Modern Trends of Colloid Science in Chemistry and Biology", Ed.HF Eicke 1985 Birkhauser Verlag Basel. Surfactants that form L _α phases at concentrations of less than 20 wt.% Are not suitable.

 In the context of this invention, amphoteric surfactants are defined as substances with molecular structures consisting of a hydrophilic and hydrophobic moiety. The hydrophobic part consists of a hydrocarbon and the hydrophilic part consists of a positive and negative group. Preferred amphoteric surfactants include amine oxides, betaines including sulfobetaines and tegobetaines, phosphine oxides and sulfoxides.

 Mixtures of solubilizing agents may be used.

 For compositions in the solid phase, in particular powder, solubilization is preferably carried out at room temperature, as this provides solid particles of the composition.

It is especially advantageous if the solubilizing agent contains, in addition, a non-surface active co-solubilizer. Preferred co-solubilizers include propylene glycol, urea, C ₆ chain length amides, citric acid and other polycarboxylic acids, which are presented in EP 0404471 (Unilever) (Unilever), glycerin, sorbitol and sucrose. Particularly preferred are polyethylene glycols, (PEG) having a molecular weight in the range of 200 to 6000, most preferably from 1000 to 2000.

 Preferably, the ratio of the co-solubilizer to the amphoteric surfactant is from 2: 1 to 1:40. Preferably, the ratio of the co-solubilizer to the nonionic surfactant is less than 1: 1, more preferably 1: 5.

 Advantageously, if the weight ratio of the solubilizing agent (it is also appropriate to include a co-solvent) to the tissue softening compound is more than 1: 6, preferably more than 1: 4, more preferably equal to or more than 2: 3. Advantageously, the ratio of the solubilizing agent to the tissue softening compound is equal to or less than 4: 1, more preferably when it is less than 3: 2.

 It is advantageous if the solubilizing agent / co-solubilizer is present in an amount of more than 5 wt.% Relative to the total weight of the composition, preferably more than 10 wt.%.

 The solubilizing agent / co-solubilizer may be present in an amount of more than 20 wt.% Relative to the total weight of the composition, or more than 30 wt.%. Such increased amounts are particularly preferred when the fabric softening composition is solid.

pH of the composition
The compositions of the invention preferably have a pH of more than 1.5, more preferably less than 5.

Other ingredients
The compositions may also contain fatty acids, for example C ₈ -C ₂₄ alkyl or alkenyl monocarboxylic acids or polymeric carboxylic acids. Saturated fatty acids, in particular solidified C ₁₆ -C ₁₈ solid fatty acids, are preferably used.

 The amount of fatty acids is preferably more than 0.1% by weight, more preferably more than 0.2% by weight.

 Particularly preferred are concentrates comprising from 0.5 to 20% by weight of a fatty acid, more preferably from 1% to 10% by weight, the ratio of tissue softening to fatty acid compound is preferably from 10: 1 to 1:10.

 Compositions in accordance with the present invention may contain detergent modifiers and / or anionic surfactants, when desired. However, it is particularly preferred that the composition is substantially free of modifying additives. It is also preferred that the composition is substantially free of anionic surfactant.

 It is suitable that the composition is substantially free of nonionic hydrophobic organic substances, for example hydrocarbons and hydrocarbyl esters of fatty acids.

 The compositions may also contain one or more optional ingredients selected from non-aqueous solvents, buffers, perfumes, fragrance carriers, fluoresceins, dyes, hydrotropic compounds, anti-foam additives, anti-redeposition additives, polymeric or other thickeners, enzymes, optical brighteners, silencers, anti-shrink agents, anti-wrinkle agents, anti-stain agents, germicides, fungicides, antioxidants, substances, etc. dotvraschayuschih corrosion, drapery agents, antistatic agents and means for ironing.

Product form
The product may take any form. Particularly preferred forms are liquid and solid compositions and compositions suitable for coating a sheet used in a dryer. A solid composition in this context includes compositions in the form of a tablet, gel, paste, and preferably granules or powder.

 The compositions can be used in a tumble dryer, but it is preferable to use it in a washing machine, for example by dispensing the composition through a metering device of the washing machine, optionally with dilution before dosing and a metering device.

Preparation of composition
The invention also provides a method for preparing a rinse conditioner as described above, the method comprising the steps of:
(i) mixing a substantially water-insoluble compound to soften the tissue and the solubilizing agent, preferably by co-melting,
(ii) adding the resulting mixture to conventional ingredients, such as water.

 Alternatively, the composition may be prepared by independently adding a water-insoluble compound to soften the tissue and solubilizing agent to conventional ingredients.

 Solid form compositions may be prepared by spray drying, freeze drying, grinding, extraction, cryogenic grinding, or any other suitable means.

 The invention will now be illustrated by the following non-limiting examples. In the examples, all percentages are expressed by weight.

 Comparative examples are indicated by letters, while examples of the invention are indicated by numbers.

Methods for getting examples
The following examples were obtained using one of the following methods:
1) Co-melting the fabric softening compound with a solubilizing agent and adding the resulting dispersion to the required amount of hot water.

 2) The sequential addition of a tissue softening compound and a solubilizing agent to hot water.

 In comparative cases where there is no solubilizing agent, a cationic substance (liquid compositions) is dispersed in hot water.

In the examples:
HT TMAPC = 1.2 bis (cured thalloyloxy / -3-trimethylammonium propane chloride,
DEQA = di (thalloyloxyethyl) dimethylammonium chloride.

 Assessment of softness.

Emollients were evaluated by adding, at ambient temperature, 10 ^° F, 0.1 g of a tissue softening compound (2 ml of a 5% dispersion) to 1 liter of tap water containing 0.001% (w / w) sodium alkylbenzenesulfonate (ABS) in a thermometer. ABS was added to stimulate the transfer of anionic detergent from the main wash. Three pieces of fleecy towel material (8 cm x 8 cm, total weight 40 g) were added to the tergotometric tank. Pieces of material for 5 minutes were processed at a speed of 65 rpm, dried in a centrifuge to remove excess fluid and dried overnight.

 Fabric softening was evaluated by an expert team of 4 people using a comparative test report in duplicate with the signatures located in a circle.

 Each expert member evaluated four rows of test pieces of matter. Each row of test pieces of matter contained in the evaluation one tissue of each test system. Expert panel members were asked to rate softness on an 8-point scale. Softness was calculated using the Change Analysis technique. Lower values indicate better mitigation.

 Examples 1 to 3

 In accordance with any of the standard methods, the following examples were obtained (Table 1, see end of description).

 Examples show good dispersibility and distributability.

 Examples 4 to 7 and A and B.

 Compositions having a range of ratios of a tissue softening compound to a solubilizing agent are prepared according to any of the methods described above in the preparation of examples. Determined emollient properties (table. 2 see at the end of the description).

 All compositions 4 to 7 showed good emollient properties and good stability. Composition A thickened under the conditions of freezing / thawing, which are described above in test III.

 Examples 8 to 14 and C to F.

 The composition was obtained by any one of the methods described to obtain examples (table. 3 see the end of the description).

The storage stability of compositions 8-14 was determined by storing the compositions under various conditions, including the freeze / thaw mode, and measuring their viscosity using a Carrimed viscometer at a shear rate of 110 sec ^-1 . The results are shown below. All comparative compositions or individual components showed poor stability (see table. 4 at the end of the description).

 All compositions in accordance with the invention showed acceptable storage stability and did not thicken in the freeze / thaw mode.

 The compositions were analyzed in accordance with test 1 described above and filtered by sequentially passing through filters with pore sizes of 1 μm, 0.45 μm and 0.2 μm to achieve separation. The amount of cationic substance remaining was measured by standard titration. (see table. 5 at the end of the description).

Compositions were analyzed under test conditions II and III described above. On a Carrie-honey viscometer, viscosity was measured at a shear rate of 110 sec ^-1 (see table. 6 at the end of the description).

 The emollient effect of the compositions was determined. The test results using a 5% solution of the compound for softening tissues and a solubilizing agent (at a ratio of 3: 2) are shown below (see table. 7 at the end of the description).

Claims (10)

1. A fabric softener composition comprising: (i) a substantially water-insoluble fabric softener compound comprising a compound having two C ₈ -C ₂₈ alkyl or alkenyl groups linked to a quaternary ammonium head group through at least one ester linkage, or a quaternary ammonium compound containing one chain with an average chain length equal to or more than C ₂₀ , and (ii) a solubilizing agent comprising an amphoteric surfactant, characterized in that the mass ratio is solubilizing its means of (ii) a tissue softening compound (i) is more than 1: 6 and when the fabric softening composition is diluted with water to a concentration of 5 wt.% relative to (i) and (ii) at least 70 wt.% of the compound to soften the tissue is in solution. 2. The composition according to p. 1, characterized in that the quaternary ammonium compound comprises a substantially water-insoluble tissue softening compound comprising a compound having C ₁₂ -C ₂₂ alkyl or alkenyl groups linked to a quaternary ammonium head group through at least one complex ether connection.  3. The composition according to claim 1 or 2, characterized in that the solubilizing agent comprises an amphoteric surfactant co-solubilizer.  4. The composition according to any preceding paragraph, characterized in that the ratio of the solubilizing agent to the compound for softening tissues is in the range from 2: 3 to 4: 1. 5. The composition according to any preceding paragraph, characterized in that the compound for softening the tissue has a solubility of less than 1 • 10 ^-3 wt.% In demineralized water at 22 ^o C.  6. A composition according to any preceding claim, characterized in that the tissue softening compound is selected from 1,2-bis (cured thalloyloxy) 3-trimethyl-ammonium propane chloride and di (thalloylethyleneoxy) dimethyl ammonium chloride.  7. The composition according to any preceding paragraph, characterized in that the level of solubilizing agent is more than 10 wt.% Relative to the entire composition.  8. The composition according to any preceding paragraph, characterized in that it is in the form of self-limiting size molecular aggregates, such as micelles or micelles of solutions with solid or liquid precursors or mixtures thereof.  9. The composition according to any preceding paragraph, characterized in that it is in the form of a liquid.  10. The composition according to any one of claims 1 to 9, characterized in that it is granular or powdered.

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