NO830420L - PROCEDURE FOR TREATMENT OF SUBSTANCES. - Google Patents

Abstract

A method of treating fabrics comprises contacting the fabrics with an aqueous liquor having a pH less than about 7.5, such as between about 5.0 and about 7.0, the liquor containing a cationic fabric softener and lanolin. The liquor is formed by adding to water a composition containing the cationic fabric softener and the lanolin, the concentration of these components in the liquor preferably being from 50 ppm to 500 ppm. The lanolin may be replaced by a lanolin-like material such as derivatives thereof or one or more of the active constituents of lanolin either extracted therefrom or derived from other sources. Preferred ratios of cationic softener to lanolin are 20:1 to 1:20 by weight. A a liquor to flabric ratio of less than 25:1 is preferred. The method generally leads to a deposition of cationic softener and lanolin of less than 0.5% by weight of the fabric.

Description

The invention relates to a fabric softening preparation and a method for using it. In particular, but not exclusively, it relates to a water-based concentrated fabric softening preparation.

It is known to treat cloth, especially after washing, with fabric softeners to improve the grip of the cloth and, in the case of clothing, to improve comfort during use. Traditionally, fabric softeners are applied from an aqueous bath made by adding a relatively small volume of a fabric softener preparation to a large volume of water, for example during the rinse cycle of an automatic washing machine. The fabric softening preparation is usually an aqueous, liquid product containing less than approx. 8% of a cationic fabric softener. For a number of reasons, including for example packaging costs, it would be preferable if the product were to contain more than 8% of the active ingredient, but due to difficulties during production, storage and ease of use of the products, it has only been possible to do this previously with some difficulty.

Furthermore, there may be a desire to partially replace the cationic fabric softener with a material that is less expensive, easier to handle or more prone to causing skin reactions, while at the same time the product's performance is maintained, at least substantially.

As set forth in more detail below, the present invention attempts to overcome one or more of the objections referred to above by the combined use of a cationic fabric softener and lanolin or a lanolin-like material.

According to the invention, a method for treating laundry is provided, comprising bringing the laundry into contact with an aqueous liquid which has a pH value below 7.5 and which contains a cationic fabric softener, characterized in that said liquid also contains lanolin or a lanolin-like material and is formed by adding to water a liquid or granular fabric softener preparation comprising a cationic fabric softener and lanolin or a lanolin-like material.

The fabric softener preparation used to form the water bath may be in the form of a granular solid, a paste, a dilute liquid (containing less than about 8% by weight of total cationic fabric softener and lanolin or lanolin-like material) or a concentrated liquid (containing more than a total of approx. 8% of these materials). The preferred form of the preparation is a water-based liquid, especially a concentrated liquid.

An essential component of the present invention is lanolin or a lanolin-like material.

Lanolin is wool wax that has been cleaned by various cleaning steps including washing, neutralization, filtration, bleaching and deodorisation. Lanolin is composed primarily of esters which constitute the active ingredients in the present invention and which upon hydrolysis give a mixture of complex alcohols and fatty acids. The alcohols that make up approx. half - of the ester component by weight, includes sterols and terpene alcohols. The sterols make up approx. 30% and includes cholesterol, 7-dehydrocholesterol and cerebosterol and dihydrocholesterol (cholestanol). The terpene alcohols include lanesterol (C3qH5o0^'dihydrolanesterol (C30^52°)'a9no~sterol (C3QH4<gO>),dihydroagnosterol (C^qH^qO).

Lanolin is commercially available in a variety of forms. Lanolin as such contains the active ingredients primarily in their ester form. It is also available in two hydrolysed forms where the active ingredients are primarily in their alcoholic or carboxylic acid form. Furthermore, lanolin can be hydrogenated so that a product is formed where the active ingredients are present primarily only in their alcoholic form. Lanolin is also commercially available in propoxylated and acetylated forms. As used herein, the term "lanolin" means any such material derived from wool wax, and whether the active ingredients are in the alcoholic, ester, alkylated, hydrogenated or other chemical form.

Suitable commercial forms of lanolin include Corona (lanolin BP), Hartolan, Polychol (trademarks of Croda Chemicals Ltd), Solulan, Acetulan and Modulan (trademarks of American Cholesterol Products Inc) and Lanocerina (trademark - Esperis SpA Milan), Coronet (trademark - Croda Chemicals Limited). Commercial lanolin is also available from Westbrook Lanolin Co., Bradford, England.

Many of the active ingredients in lanolin can be produced synthetically, from sources other than wool wax, or they can be extracted from wool wax and other naturally occurring materials. Although the commercially available forms of lanolin are preferred for price reasons in connection with the present invention, it is also possible to use any one or more of the active ingredients referred to above, but also derivatives, and also materials of similar structure. Thus, in place of lanolin, a "lanolin-like material" may be used, and this term, as used herein, includes: (a) any one or more of the active lanolin constituents referred to above, and carboxylic acid- or the alcohol derivatives thereof; (b) the corresponding carboxylic acids or alcohols and ester derivatives of the materials listed under (a), especially the esters thereof, with fatty acids or alcohols which

contains at least 12 carbon atoms.

(c) Iso- and anteiso-alcohols and acids and derivatives thereof having the general formula

where R"*" is divalent, straight chain or branched, saturated or unsaturated, substituted or unsubstituted hydrocarbyl group having at least 7, preferably at least 15, carbonato-2

more, R is a methyl or ethyl group and X is —OH,

3 3

or —COOR where R is a hydrocar-

byl group, especially a fatty acid alkyl group, containing at least 12 carbon atoms. Examples of materials in this group include 16-methylheptadecanol, 24-methyl-hexacosanol, 8-methylnonanoic acid, and 2-hydroxy-16-methyl-heptadecanoic acid.

The amount of lanolin or lanolin-like material in the aqueous fabric softening preparations is preferably from approx. 0.25 to approx. 40% by weight, for example between approx. 1.5 and approx. 20% by weight calculated on the mixture.

Any well-known cationic fabric softener can be used in connection with the present invention, as well

as mixtures of two or more of such agents.

Suitable examples of cationic fabric softeners are quaternary ammonium compounds containing two long alkyl or alkenyl chains with 12-22 carbon atoms, for example di(cured or uncured tallow) dimethylammonium chloride, 2-heptade-cyl-2-methylstearoylamidoethyl-imidazoline methosulphate, di-(coke)di -methylammonium chloride etc. These cationic fabric softeners are well known in the art and further suitable examples can be found in Schwartz-Perry: "Surface-active Agents and Detergents" Vol.II, 1958.

Relatively water-soluble cationic softeners, for example the monoalkyl-quaternary ammonium compounds, for example stearyltrimethylammonium chloride can also be used, but, as they are often less effective softeners, they are preferably used in conjunction with other, more effective cationic softeners or with non-cationic softeners, for for example fatty acid esters of polyols, for example sorbitan tristearate, glycerol monostearate, and so on, or with anionic detergents with which they have the ability to form softening complexes, for example fatty acid soaps. They can also be made more hydrophobic by treatment with suitable hydrophobicizing agents, for example long-chain alcohols and fatty acids. However, the invention is of particular use if the more effective, less water-soluble cationic softeners having two long alkyl chains are used.

The amount of cationic fabric softener in the aqueous fabric softener preparations is preferably from 0.5 to 30% by weight, for example between 1.0 and 15% by weight based on the mixture.

The weight ratio between the cationic fabric softener and lanolin or lanolin-like material can be between 0.05:1 and 20:1, more preferably between 0.1:1 and 10:1, especially between 1:1 and 4:1.

In use, the fabric softening preparation according to the invention is added to a large volume of water to form a bath with which the fabric to be treated is brought into contact. In general, the total concentration of the cationic fabric softener and lanolin or lanolin-like materials in this bath will be between 50 and 500 ppm.

The bath's pH value should be less than 7.5, and is preferably between 5.0 and 7.0.

The pH value of the aqueous preparation, which is used to form the bath, can be varied within a somewhat wider range, for example between 3 and 8, preferably from 4 to 6. To achieve the desired pH value in the preparation and in the treatment bath, the preparation can contain buffering agents as needed, for example benzoic acid, citric acid and phosphoric acids and/or their alkali metal salts.

In use, the fabric to be treated is brought into contact with an aqueous bath to which the fabric softening preparation is added, the weight ratio between fabric and bath being preferably less than 25:1, preferably between 10:1 and 4:1.

The water bath in contact with the laundry can be at any suitable temperature. Successful results can be achieved if the bath has a temperature between approx. 0 and approx. 6 0°C, preferably between approx. 10 and approx. 40°C.

The bath and the laundry that comes into contact with it are agitated

preferably during treatment.

The amount of cationic softener and lanolin or lanolin-like material that is deposited on the fabric depends, among other things, on the concentration of these components in the treatment bath, the temperature of the treatment, the degree of agitation, the treatment time and the nature of the fabric. In general, an amount of less than 0.5%, for example between 0.01% and 0.4% by weight in all of these components will be deposited, based on the weight of the dry laundry.

The rest of the preparation generally comprises the aqueous medium, possibly with the other ingredients listed below. The aqueous medium comprises at least 25%, preferably at least 30%, and especially at least 40%, of the preparation.

The preparations according to the invention may further comprise additional beneficial ingredients, usually used or proposed for incorporation in fabric softening preparations. Such ingredients, either alone or incorporated in suitable carriers, include viscosity modifiers, germicides, fluorescent agents, perfumes including deodorizing perfumes, organic or inorganic acids, antistatic agents, for example water-soluble cationic surfactants, ethoxylated quaternary polyamine compounds (e.g. "Ethoduameen"Tl3) and aluminum salts, soil release agents, coloring agents, anti-oxidants, bleaching agents, bleach precursors, anti-yellowing agents, ironing aids, etc., all in the conventional small amounts. Such enzymes as cellulases may also be included.

The preparations can also contain, in addition to the cationic fabric softeners, other non-cationic fabric softeners, for example non-ionic fabric softeners.

In particular, the preparations, when in liquid form, may include viscosity modifiers, for example polymers as described below, C±2~(~' 4 Q-hydrocarbons, Cg-C^-fatty acids, fatty acid esters with a total of 10-40 carbon atoms, C] _o~ci8~fatty alcohols, electrolytes and water-miscible solvents.

The polymer can, when included in the preparation according to the invention, be present therein in an amount of 0.5-40%, preferably 1-30%, particularly preferably 4-25%. The polymer suitable for incorporation is defined as follows: The polymer must be water-soluble under the conditions of use, and a 20% aqueous solution of the polymer must have a viscosity (tj ) of -<T50, preferably <30 and particularly preferably <15 cP, measured at 25°C and 110 sec-1 in a Haake Viscometer. Said 20% aqueous solution must also show a vapor pressure equal to or lower than the vapor pressure of a 2% aqueous solution of polyethylene glycol with a molecular weight of 6,000, preferably equal to or lower than the value for a 10% aqueous solution of said polyethylene glycol, and particularly preferred equal to or lower than the value for an 18% aqueous solution of said polyethylene glycol. Said aqueous polymer solution may be of water and polymer alone or may include solvent-containing media normally derived from the raw materials or additives, or may include additives specifically intended to improve the vapor pressure lowering capacity of the polymer, or, in the case of ionic polymers, include adjustments to the pH value to optimize ionization. Such vapor pressure measurements can be obtained with a Hewlett Packard vapor pressure osmometer, using an operating temperature of 34.5°C or using any other suitable vapor measuring device.

The polymer must furthermore have a molecular weight of at least 400, preferably at least 4000 and particularly preferably at least 6000.

It is also desirable that the polymer does not interact negatively with any of the other ingredients in the preparation.

Suitable examples of the polymer can thus be obtained from the polyalkylene glycols, the polyalkylene imines, dextran, gelatin and other natural or synthetic (co)polymers, when they only satisfy the above-mentioned criteria.

Mixtures of two or more polymers of the same type or a different type can also be used.

A preferred class of polymers comprises polyethylene glycols with an average molecular weight of 1000 - 6000. These polymers, and especially those having an average molecular weight of 4000 or 6000, are particularly suitable for preparations according to the invention which have a high level of relative water -insoluble cationic fabric softener.

Other typical examples of suitable polymers are dextran with a molecular weight of 10,000 and polyethyleneimine with a molecular weight of 45-750.

When the preparation contains a C12~C4g hydrocarbon as viscosity-regulating agent, this is advantageous in an amount of 0.25-50% by weight, preferably 0.5-25%. Preferred materials have 12-24 carbon atoms, and particularly preferred are liquid mixtures of paraffins having 14-18 carbon atoms.

Normally, suitable hydrocarbons are found in the paraffin and olefin series, but other materials, such as alkynes and cyclic hydrocarbons, are not excluded. Materials generally known as paraffin oil and petroleum are suitable. Examples of specific materials are hexadecane, octadecane, eicosane-tetra-decane and octadecane. Preferred commercially available paraffin blends include spindle oil and light oil and blends of technical grade C-j^-C-^g-n paraffins. Halogen paraffins, for example myristyl chloride and stearyl bromide, are not excluded.

When the preparation contains a <C>g<->C^-f acetic acid, this is preferably in an amount of 0.5-15%.

Strongly preferred materials from this class are the C -C -saturated fatty acids, especially lauric acid, myristic acid,

listen u

palmitic acid and stearic acid.

When the preparation contains a fatty acid ester which has a total of 10-40 carbon atoms, this is in a preferred amount of 0.25-15% by weight, advantageously 0.5-4%. The ester preferably originates empirically from a fatty acid having 8-2 3 carbon atoms and an alkanol or hydroxyalkanol having 1-8, especially 1-4 carbon atoms. Specific examples include esters derived from C^-C^ alcohols and lauric, myristic, palmitic or stearic acid, for example methyl laurate, ethyl myristate, iso-propyl stearate, ethylene glycol monostearate,•ethyl stearate, methyl palmitate and other esters, for example iso- butyl stearate, 2-ethylhexyl laurate, iso-octyl myristate.

When the preparation contains a fatty alcohol having 10-18 carbon atoms, this is preferably in an amount of 0.25-15% by weight.

Specific examples of this class are decanol, dodecanol, tetradecanol, pentadecanol, hexadecanol and octadecanol. The most preferred examples are lauryl and palmityl alcohols.

When the preparations contain a solvent as viscosity-regulating agent, this can be a lower alkanol, a glycol, a glycol ether and the like. The solvent may be present in an amount of up to 20% by weight, for example 5-15% by weight. When the cationic fabric softener is supplied in the form of an aqueous-alcoholic solution, the alcohol content includes the above amounts, and if necessary, only a small amount of additional alcohol should be added. A suitable solvent is isopropanol.

The viscosity of the fabric softening preparation can be regulated by the presence of an electrolyte. Preferably, the electrolyte is a water-soluble non-surfactant salt, for example sodium chloride, sodium methosulphate, sodium benzoate-calcium chloride, magnesium chloride or aluminum chloride hydrate. The level of electrolyte will determine or be determined by the desired viscosity of the preparation and the nature and concentration of other components in the preparation. Typical levels are from 100 to 1000 ppm, preferably between 200 and 500 ppm.

The fabric softening preparations optionally contain one or more non-ionic emulsifiers, for example the polymerised monoglycerides of long-chain fatty acids which have 14-24 carbon atoms in the straight or branched saturated or cross-linked carbon chain, for example poly-monolauryl glyceride, poly-monostearyl glyceride, poly-monopalmityl glyceride or poly-monooleyl glyceride. Another suitable nonionic emulsifier is sorbitan monostearate.

These nonionic emulsifiers are available commercially under the trade names WITCONOL (Witco Chemicals Ltd) and SPAN

(Atlas Chemical). The nonionic emulsifier may be present in a content of 0.5-9.5% by weight, for example 2.4-6%.

In addition to the components mentioned above, the preparations according to the invention can also include a water-soluble cationic or non-ionic surfactant.

Water-soluble means that the surfactant has a solubility in water of pH 2.5 and at 20°C of more than 10 g/l. Normally, such materials are alkyl-substituted ammonium salts which have one C-^2-C24~ alkyl chain, optionally substituted or interrupted by functional groups such as —0—, —COO—,—CONH—,—0— etc. Suitable water-soluble nonionic surfactants are the ethoxylated sorbitan esters available as TWEENS (Atlas Chemical).

It is particularly advantageous to include a water soluble

cationic or non-ionic emulsifier in the preparation if it contains, as viscosity modifier, a hydrocarbon, a fatty acid, fatty alcohol or fatty acid ester of the types referred to above. The amount of the water-soluble surfactant is preferably 0.1-1%.

Preferably, the preparations contain practically no anionic material such as anionic surfactants. However, some anionic material can be tolerated in practice. In preferred mixtures, the weight ratio between any anionic material and the cationic fabric softener is less than 0.4:1, preferably less than 0.2:1.

The viscosity of the fabric softening preparations, when they are in liquid form, is preferably below approx. 150 cP, preferably below approx. 120 cP. This viscosity is measured at 25°C and 110 sec 1 in a Haake Viscometer.

The preparations according to the invention can normally be prepared by mixing the ingredients together in water, heated to a temperature of approx. 60°C and agitate for 5-30 minutes.

In the following, the invention will be illustrated by means of the non-limiting examples.

Examples 1 to 6

Liquid fabric conditioning preparations were made according to the recipes given in the following Table I, by mixing the ingredients together in water at approx. 60°C and agitate.

Each mixture was then added to tap water at the concentrations indicated in the table, and the pH value was measured.

Each rinse bath thus obtained had the ability to provide good

fabric softener.

Table I also reproduces the viscosity of each fabric softener preparation measured in the Haake viscometer at 110 sec ^ and 25°C.

Similar results can be obtained by replacing the lanolin used in these examples with "Coronet" grade lanolin (from Croda Chemicals) or Lanolin P95 (from Westbrook Lanolin Company).

Similar results can also be achieved by using, such as the cationic fabric softener "Arquad" 2T or "Arquad" 2HT (from Armak-Company). Still further similar results can be obtained by replacing the sodium chloride with calcium chloride, mag-

nesi-tm chloride or aluminum chlorohydrate.

Example 7

Three fabric softening preparations were prepared according to the following table.

Pieces of terry cloth were treated with baths made from these preparations. The treated pieces of cloth were judged by a jury of persons who found that mixture B gave more preferable results than each of mixtures A and C.

Examples 8 and 9

The following fabric softening preparations were made using lanolin-like materials in place of lanolin as such:

The pH value of each of these preparations, after dilution to 250 ppm, was below 7.5.

Remarks:

1 - Distilled lanolin alcohols (from Croda Chemicals)

2 - Iso-stearic acid (from Emery)

Unless otherwise noted, all percentages stated herein are by weight based on the weight of the mixture.

Claims (6)

1. Method for treating laundry which comprises bringing the laundry into contact with an aqueous bath that has a pH value below approx. 7.5 and contains a cationic fabric softener, characterized in that a bath is used which also contains lanolin or a lanolin-like material and is formed by adding water to a liquid or granular, solid fabric softener preparation comprising a cationic fabric softener and lanolin or a lanolin-like material. 2. Method as stated in claim 1, characterized in that a weight ratio between lanolin or lanolin-like material and fabric softener of between 0.05:1 and 20:1 is used. 3. Method as stated in claim 2, characterized in that a weight ratio between lanolin or lanolin-like material and fabric softener of between 0.01:1 and 10:1 is used. 4. Method as specified in claim 1, characterized in that a weight ratio between said bath and said laundry of less than 25:1 is used. 5. Method as stated in claim 1, characterized in that a weight ratio between said bath and said laundry of between 10:1 and 4:1 is used. 6. Method as stated in claim 1, characterized in that a bath is used which has such a composition and that the treatment is carried out at such a temperature for such a period of time and with such agitation that the amount of cationic fabric softener and lanolin or lanolin-like material which is deposited on the laundry, is less than 0.5% by weight calculated on dry laundry.