Detergent compositions containing soil release polymers

Abstract

A non-bleaching laundry detergent composition suitable for washing delicate fabrics, having a 1 wt % aqueous solution pH in demineralised water at 25.degree. C. not exceeding 10, contains surfactant, detergency builder, and a soil release polymer which is a defined water-soluble or water-dispersible sulphonated non-end-capped polyester, for example, of terephthalic acid, isophthalic acid, sulphoisophthalic acid and ethylene glycol.

Description

TECHNICAL AREA

The present invention relates to non-bleaching laundry detergent compositions suitable for washing delicate fabrics, containing certain water-soluble or water-dispersible polyesters exhibiting improved soil release properties.

BACKGROUND AND PRIOR ART

Polyesters of terephthalic and other aromatic dicarboxylic acids having soil release properties are widely disclosed in the art, in particular, the so-called PET/POET (polyethylene terephthalate/polyoxyethylene terephthalate) and PET/PEG (polyethylene terephthalate/polyethylene glycol) polyesters which are disclosed, for example, in U.S. Pat. No. 3,557,039 (ICI), GB 1 467 098 and EP 1305A (Procter & Gamble). Polymers of this type are available commercially, for example, as Permalose, Aquaperle and Milease (Trade Marks) (ICI) and Repel-O-Tex (Trade Mark) SRP3 (Rhone-Poulenc). Other patent publications disclosing soil release polymers which are condensation products of aromatic dicarboxylic acids and dihydric alcohols include EP 185 427A, EP 241 984A, EP 241 985A and EP 272 033A (Procter & Gamble).

EP 357 280A (Procter & Gamble) discloses sulphonated end-capped linear terephthalate oligomers which are condensation products of a low molecular weight diol, preferably propylene glycol or ethylene glycol, with terephthalic acid.

The present invention is based on the use of a class of non-end-capped sulphonated polyesters based on dicarboxylic acids and polyols which provide especially effective soil release, especially from polyester fabrics, and which are also effective in reducing soil redeposition in the wash.

DEFINITION OF THE INVENTION

The present invention accordingly provides a non-bleaching laundry detergent composition suitable for washing delicate fabrics, having a 1 wt % aqueous solution pH in demineralised water at 25.degree. C. not exceeding 10 and comprising:

(a) from 2 to 50 wt % of an organic surfactant system comprising one or more anionic, nonionic, cationic, amphoteric or zwitterionic surfactants, (b) from 0 to 80 wt % of a builder component comprising one or more inorganic or organic detergency builders, (c) a soil release effective amount of a water-soluble or water-dispersible sulphonated polyester comprising monomer units of (i) an unsulphonated aromatic diacidic monomer (A), (ii) a sulphonated aromatic diacidic monomer (SA) (iii) optionally a hydroxylated aromatic or aliphatic diacidic monomer (HA), in an amount replacing up to 50 mole % of (A) and/or (SA), (iv) a polyol (P) selected from ethylene glycol, propylene glycol, isopropylene glycol, glycerol, 1,2,4-butanetriol and 1,2,3-butanetriol, and oligomers of these having from 1 to 8 monomer units, the polyester having a sulphur content within the range of from 0.5 to 10 wt %; (d) optionally other detergent ingredients to 100 wt %.

DETAILED DESCRIPTION OF THE INVENTION

The Polyesters

The polyesters with which the invention is concerned are defined above. The polyesters and their preparation are disclosed and claimed in WO 95 32997A (Rhone-Poulenc).

Preferred polyesters have the following features:

the unsulphonated diacidic monomer (A) is an aromatic dicarboxylic acid or an anhydride of a lower (C.sub.1 -C.sub.4) alkyl diester thereof, selected from terephthalic acid, isophthalic acid, 2,6-naphthalene dicarboxylic acid, anhydrides and lower (C.sub.1 -C.sub.4) alkyl diesters thereof; the sulphonated diacidic monomer (SA) is a sulphonated aromatic dicarboxylic acid, anhydride, or lower (C.sub.1 -C.sub.4) alkyl diester thereof; the mole ratio (A):�(A)+(SA)! is within the range of from 60:100 to 95:100, preferably from 65:100 to 93:100; the mole ratio (SA):�(A)+(SA)! is within the range of from 5:100 to 40:100, preferably from 7:100 to 35:100; the hydroxylated monomer (HA), if present, is a hydroxylated aromatic dicarboxylic acid, or anhydride or lower (C.sub.1 -C.sub.4) dialkyl ester thereof; the hydroxylated monomer (HA), if present, does not replace more than 30 mole % of (A) and/or (SA); the quantity of (P) is such that the ratio of OH functional groups of (P) to COOH functional groups (or equivalents) of (A)+(SA)+any (HA) is within the range of from 1.05:1 to 4:1, preferably from 1.1:1 to 3.5:1, and more preferably from 1.8:1 to 3:1; the polyester has a number average molecular weight of less than 20 000, the sulphur content is within the range of from 1.2 to 8 wt %; the hydroxyl group content is at least 0.2 OH equivalent per kg of polyester. The Unsulphonated Diacidic Monomer (A)

As previously indicated, the monomer (A) preferably consists of at least one dicarboxylic acid or anhydride chosen from terephthalic, isophthalic and 2,6 naphthalenedicarboxylic acids or anhydrides or their diesters.

Preferably, monomer (A) is present in a quantity corresponding to a molar ratio (A)/�(A)+(SA)! within the range of from 95:100 to 60:100, preferably from 93:100 to 65:100.

The unsulphonated diacidic monomer (A) preferably consists of 50 to 100 mole %, more preferably 70 to 90 mole %, of terephthalic acid or anhydride or lower alkyl (methyl, ethyl, propyl, isopropyl, butyl) diester, and of 0 to 50 mole %, more preferably from 10 to 30 mole %, of isophthalic acid or anhydride and/or of 2,6-naphthalenedicarboxylic acid or anhydride or lower alkyl (methyl, ethyl, propyl, isopropyl, butyl) diester; the preferred diesters are methyl diesters.

In the unsulphonated diacidic monomer (A) there may additionally be present minor quantities of aromatic diacids other than those mentioned above, such as ortho-phthalic acid, anthracene, 1,8-naphthalene, 1,4-naphthalene and biphenyl dicarboxylic acids or aliphatic diacids such as adipic, glutaric, succinic, trimethyladipic, pimelic, azelaic, sebacic, suberic, itaconic and maleic acids, etc. in the form of acid, anhydride or lower (methyl, ethyl, propyl, isopropyl, butyl) diesters.

The Sulphonated Diacidic Monomer (SA)

Preferably, the sulphonated diacidic monomer (SA) consists of at least one sulphonated aromatic or sulphonated aliphatic dicarboxylic acid or anhydride or lower (C.sub.1 -C.sub.4) alkyl diester. Aromatic dicarboxylic acids and their derivatives are preferred.

Preferably, monomer (SA) is present in a quantity corresponding to a molar ratio (SA)/�(A)+(SA)! within the range of from 5:100 to 40:100, more preferably from 7:100 to 35:100.

The sulphonated diacidic monomer (SA) has at least one sulphonic acid group, preferably in the form of an alkali metal (preferably sodium) sulphonate, and two acidic functional groups or acidic functional group equivalents (that is to say an anhydride functional group or two ester functional groups) attached to one or a number of aromatic rings, when aromatic dicarboxylic acids or anhydrides or their diesters are involved, or to the aliphatic chain when aliphatic dicarboxylic acids or anhydrides or their diesters are involved.

Suitable aromatic sulphonated diacidic monomers include sulphoisophthalic, sulphoterephthalic, sulpho-ortho-phthalic acids or anhydrides, 4-sulpho-2,7-naphthalenedicarboxylic acids or anhydrides, sulpho 4,4'-bis (hydroxycarbonyl) diphenyl sulphones, sulphodiphenyldicarboxylic acids or anhydrides, sulpho 4,4'-bis(hydroxycarbonyl) diphenylmethanes, sulpho-5-phenoxyisophthalic acids or anhydrides or their lower (methyl, ethyl, propyl, isopropyl, butyl) diesters.

Suitable aliphatic sulphonated diacidic monomers (SA) include sulphosuccinic acids or anhydrides or their lower alkyl (methyl, ethyl, propyl, isopropyl, butyl) diesters.

The most preferred sulphonated diacidic monomer (SA) is sulphoisophthalic acid in acid, anhydride or diester (preferably dimethyl ester) form, very particularly dimethyl 5-sodiooxysulphonylisophthalate.

The Hydroxylated Diacidic Monomer (HA)

The hydroxylated diacidic monomer (HA), which is optionally present and can replace up to 50 mole %, preferably up to 30 mole %, of (A) and/or (SA), consists of least one hydroxylated aromatic or aliphatic dicarboxylic acid or anhydride or a lower (C.sub.1 -C4) alkyl diester thereof.

The hydroxylated diacidic monomer (HA) has at least one hydroxyl group attached to one or a number of aromatic rings when it is an aromatic monomer or to the aliphatic chain when it is an aliphatic monomer. Aromatic monomers are preferred.

Suitable hydroxylated diacidic monomers (HA) include 5-hydroxyisophthalic, 4-hydroxyisophthalic, 4-hydroxyphthalic, 2-hydroxymethylsuccinic, hydroxymethylglutaric and hydroxyglutaric acids, in acid, anhydride or lower alkyl diester form.

The Polyol (P)

The polyol (P) may be a oligomer comprising up to 8 monomer units, preferably up to 6 and more preferably up to 4 monomer units, but is most preferably a monomer. The polyol is selected from ethylene glycol, propylene glycol, glycerol, 1,2,4-butanetriol, 1,2,3-butanetriol and combinations of these, and their lower (2 to 8, preferably 2 to 6, more preferably 2 to 4) oligomers.

Preferably, the polyol (P) is present in a quantity corresponding to a ratio of the number of OH functional groups of the polyol (P) to the number of COOH functional groups or functional group equivalents of the total diacidic monomer (A)+(SA)+(HA) within the range of from 1.05:1 to 4:1, preferably from 1.1:1 to 3.5:1 and more preferably from 1.8:1 to 3:1.

The preferred polyols (P) are ethylene glycol and glycerol, ethylene glycol being especially preferred.

Preferably, the sulphonated diacidic monomer (SA) consists of at least one sulphonated aromatic dicarboxylic acid or anhydride or of a mixture of sulphonated aromatic acids or anhydrides and of sulphonated aliphatic acids or anhydrides or their diesters when the polyol (P) does not contain any polyol other than a glycol or when the hydroxylated diacidic monomer (HA) is absent.

Molecular Weight

Preferably, the polyester used in accordance with the invention has a number average molecular weight not exceeding 20 000, and preferably not exceeding 15 000.

The molecular weight may be much lower than these limits. Polyesters having molecular weights below 1000, for example, 500-1000, have proved highly effective.

Number average molecular weight may be measured by gel permeation chromatography, for example, in dimethylacetamide containing 10.sup.-2 N of LiBr, at 25.degree. C., or in tetrahydrofuran. The results are expressed as polystyrene equivalents.

Hydroxyl Functional Group Content

Preferably, the hydroxyl functional group content of the polyester, expressed as OH equivalent/kg of polyester, is at least 0.2. The hydroxyl functional group content may be estimated from proton NMR, the measurement being carried out in dimethyl sulphoxide.

The elementary unit considered in the definition of the mole of monomer (A), (SA) or (HA) is the COOH functional group in the case of the diacids or the COOH functional group equivalent in the case of the anhydrides or of the diesters.

Especially Preferred Polyesters

An especially preferred polyester is obtainable from the following monomers:

terephthalic acid (A1) in lower alkyl (preferably methyl) diester form; optionally isophthalic acid (A2) in acid or anhydride form; optionally a hydroxylated terephthalic or isophthalic acid (HA) in acid or anhydride form; the mole ratio (A1):�(A1)+(A2)! or (A1):�A1+HA)! or (A1):�(A1)+(A2)+(HA)! being within the range of from 50:100 to 100:100, preferably from 70:100 to 90:100; sulphoisophthalic acid (SA), preferably in lower alkyl, preferably methyl, diester form; and monoethylene glycol and/or glycerol (P).

Preferred polyesters in accordance with the invention, based on terephthalic acid, isophthalic acid, sulphoisophthalic acid and monoethylene glycol, may be described as having backbone units of the following formula: ##STR1## where Ar=terephthalic, isophthalic or sulphoisophthalic, and n represents 1, 2, 3 or 4. Typical mole percentages for the different values of n are as follows:

______________________________________ n = 1 58.7 n = 2 30.5 n = 3 8.8 n = 4 1.9,______________________________________ only trace quantities, if any, of polyethylene oxide units in which n is greater than four being present.

The majority of endgroups are of the formula

--Ar--COO--(CH.sub.2 --CH.sub.2 --O--).sub.n wherein n is 1, 2, 3 or 4, a minority being of the formulae --Ar--COOH or --Ar--COOR wherein R is a lower alkyl group, preferably methyl.

These polyesters, unlike many disclosed in the prior art, are not end-capped with hydrocarbon or sulphonated capping groups.

Preparation of the Polyesters

The polyesters may be prepared by the usual esterification and/or transesterification and polycondensation processes, for example, by esterification and/or transesterification in the presence of a catalyst of the polyol P with the various diacidic monomers (in acid, anhydride or diester form), and polycondensation of the polyol esters at reduced pressure in the presence of a polycondensation catalyst.

A preferred process for the preparation of the polyesters is disclosed and claimed in WO 95 32997A (Rhone-Poulenc).

Detergent Compositions

The polyesters are suitably incorporated into detergent compositions in amounts of from 0.01 to 10 wt %, preferably from 0.1 to 5 wt % and more preferably from 0.25 to 3 wt %.

The detergent compositions of the invention also contain, as essential ingredients, one or more detergent-active compounds (surfactants), and may also contain one or more detergency builders; they may also optionally contain other active ingredients to enhance performance and properties.

Surfactant System

The detergent-active compounds (surfactants) may be chosen from soap and non-soap anionic, cationic, nonionic, amphoteric and zwitterionic detergent-active compounds, and mixtures thereof. Many suitable detergent-active compounds are available and are fully described in the literature, for example, in "Surface-Active Agents and Detergents", Volumes I and II, by Schwartz, Perry and Berch. The preferred detergent-active compounds that can be used are soaps and synthetic non-soap anionic and nonionic compounds. The total amount of surfactant present ranges from 2 to 50 wt %, preferably from 5 to 40 wt %.

Anionic surfactants are well-known to those skilled in the art. Examples include alkylbenzene sulphonates, particularly linear alkylbenzene sulphonates having an alkyl chain length of C.sub.8 -C.sub.15 ; primary and secondary alkylsulphates, particularly C.sub.8 -C.sub.15 primary alkyl sulphates; alkyl ether sulphates; olefin sulphonates; alkyl xylene sulphonates; dialkyl sulphosuccinates; and fatty acid ester sulphonates. Sodium salts are generally preferred.

The polyesters of the present invention are especially suitable for use in compositions containing anionic sulphonate and sulphate type surfactants, for example, primary alkyl sulphates, alkyl ether sulphates, alkylbenzene sulphonates, and mixtures of these.

Nonionic surfactants that may be used include the primary and secondary alcohol ethoxylates, especially the C.sub.8 -C.sub.20 aliphatic alcohols ethoxylated with an average of from 1 to 20 moles of ethylene oxide per mole of alcohol, and more especially the C.sub.10 -C.sub.15 primary and secondary aliphatic alcohols ethoxylated with an average of from 1 to 10 moles of ethylene oxide per mole of alcohol. Non-ethoxylated nonionic surfactants include alkylpolyglycosides, glycerol monoethers, and polyhydroxyamides (glucamide).

Especially preferred are ethoxylated nonionic surfactants, alkylpolyglycosides, and mixtures of these.

As well as the non-soap surfactants listed above, detergent compositions of the invention may also advantageously contain fatty acid soap.

Detergency Builder System

The detergent compositions of the invention will generally also contain one or more detergency builders. The total amount of detergency builder in the compositions will suitably range from 5 to 80 wt %, preferably from 10 to 60 wt %.

Inorganic builders that may be present include sodium carbonate, if desired in combination with a crystallisation seed for calcium carbonate, as disclosed in GB 1 437 950 (Unilever); crystalline and amorphous aluminosilicates, for example, zeolites as disclosed in GB 1 473 201 (Henkel), amorphous aluminosilicates as disclosed in GB 1 473 202 (Henkel) and mixed crystalline/amorphous aluminosilicates as disclosed in GB 1 470 250 (Procter & Gamble); and layered silicates as disclosed in EP 164 514B (Hoechst). Inorganic phosphate builders, for example, sodium orthophosphate, pyrophosphate and tripolyphosphate, may also be present.

According to one preferred embodiment of the invention, the detergent compositions of the invention preferably contain an alkali metal, preferably sodium, aluminosilicate builder. Sodium aluminosilicates may generally be incorporated in amounts of from 10 to 70% by weight (anhydrous basis), preferably from 25 to 50 wt %.

The zeolite may be the commercially available zeolite 4A now widely used in laundry detergent powders. Other zeolites that may be used include zeolites X and Y. Alternatively, and preferably, the zeolite builder incorporated in the compositions of the invention is maximum aluminium zeolite P (zeolite MAP) as described and claimed in EP 384 070B (Unilever). Zeolite MAP is defined as an alkali metal aluminosilicate of the zeolite P type having a silicon to aluminium ratio not exceeding 1.33.

Especially preferred is zeolite MAP having a silicon to aluminium ratio not exceeding 1.07, more preferably about 1.00. The calcium binding capacity of zeolite MAP is generally at least 150 mg CaO per g of anhydrous material.

According to another preferred embodiment of the invention, the builder system comprises at least 5 wt %, and preferably at least 10 wt %, of sodium tripolyphosphate (the percentages being based on the detergent composition). Sodium tripolyphosphate is suitably present in an amount of from 5 to 50 wt %; if sole builder, it is suitably present in an amount of from 20 to 50 wt %.

Sodium tripolyphosphate may also advantageously be used in combination with other builders, most preferably, sodium carbonate, sodium orthophosphate, sodium pyrophosphate, or sodium aluminosilicate (zeolite). One preferred mixed builder system comprises at least 5 wt % sodium tripolyphosphate in combination with at least 10 wt % of zeolite A.

Organic builders that may be present include polycarboxylate polymers such as polyacrylates, acrylic/maleic copolymers, and acrylic phosphinates; monomeric polycarboxylates such as citrates, gluconates, oxydisuccinates, glycerol mono-, di- and trisuccinates, carboxymethyloxysuccinates, carboxymethyloxymalonates, dipicolinates, hydroxyethyliminodiacetates, alkyl- and alkenylmalonates and succinates; and sulphonated fatty acid salts. This list is not intended to be exhaustive.

Solution pH

The compositions of the invention, which are non-bleaching formulations especially suitable for washing delicate fabrics, produce a wash liquor of low pH. The 1 wt % solution pH at 25 C. in demineralised water of the compositions of the invention does not exceed 10, and is preferably within the range of from 9.5 to 10.

Other Care Ingredients

The compositions of the invention may advantageously possess one or more of the following characteristics:

absence, or an extremely low level, of fluorescer; presence of a polycarboxylate polymer, for example, an acrylic/maleic copolymer such as Sokalan (Trade Mark) CP5 ex BASF; presence of a polymer effective to inhibit dye transfer, for example, polyvinyl pyrrolidone; presence of a heavy metal sequestrant, for example, aminomethylenephosphonic acids and salts such as ethylenediamine tetramethylene phosphonate (EDTMP) and its salts, and diethylenetriamine pentamethylene phosphonate (DETPMP) and its salts. presence of at least two enzymes.

Suitable enzymes include the proteases, amylases, cellulases and lipases usable for incorporation in detergent compositions.

Preferred proteolytic enzymes (proteases) are normally solid, catalytically active protein materials which degrade or alter protein types of stains when present as in fabric stains in a hydrolysis reaction. They may be of any suitable origin, such as vegetable, animal, bacterial or yeast origin.

Proteolytic enzymes or proteases of various qualities and origins and having activity in various pH ranges of from 4-12 are available and can be used in the present invention. Examples of suitable proteolytic enzymes are the subtilisins, which are obtained from particular strains of B. subtilis and B. licheniformis, such as the commercially available subtilisins Maxatase (Trade Mark), as supplied by Gist-Brocades N. V., Delft, Holland, and Alcalase (Trade Mark), as supplied by Novo Industri A/S, Copenhagen, Denmark.

Also suitable is a protease obtained from a strain of Bacillus having maximum activity throughout the pH range of 8-12, being commercially available, e.g. from Novo Industri A/S under the registered trade-names Esperase (Trade Mark) and Savinase (Trade Mark). The preparation of these and analogous enzymes is described in GB 1 243 785. Other commercial proteases are Kazusase (Trade Mark) (obtainable from Showa-Denko of Japan), Optimase (Trade Mark) (from Miles Kali-Chemie, Hannover, West Germany), and Superase (Trade Mark) (obtainable from Pfizer of U.S.A.).

Proteases having isoelectric points below 10 include Alcalase, Maxatase, Optimase and Primase (all Trade Marks). Proteases having isoelectric points of 10 or above include Savinase, Maxacal, Purafect, Opticlean and Esperase (all Trade Marks).

Detergency enzymes are commonly employed in granular form in amounts of from 0.01 to 5.0 wt %.

Preferably the compositions of the invention contain at least two enzymes, which are preferably a protease and a lipase. Optionally an amylase and/or a cellulase may also be present.

In particulate compositions of the invention, the enzymes are suitably present in granular form. The compositions may then suitably contain protease granules in an amount of from 0.1 to 5 wt % and lipase granules in an amount of from 0.01 to 1 wt %, or protease/lipase granules in an amount of from 0.1 to 5 wt %; and optionally amylase granules in an amount of from 0.01 to 1 wt %, and/or cellulase granules in an amount of from 0.01 to 1 wt %.

Other materials that may be present in detergent compositions of the invention include inorganic salts such as sodium carbonate, sodium sulphate or sodium silicate; antiredeposition agents such as cellulosic polymers; inorganic salts such as sodium sulphate; lather control agents or lather boosters as appropriate; dyes; coloured speckles; perfumes; foam controllers; and fabric softening compounds. This list is not intended to be exhaustive.

Detergent compositions of the invention may be of any suitable physical form, for example, powders or granules, liquids, gels and solid bars.

Detergent compositions of the invention may be prepared by any suitable method. Particulate detergent compositions are suitably prepared by spray-drying a slurry of compatible heat-insensitive ingredients, and then spraying on or postdosing those ingredients unsuitable for processing via the slurry. The skilled detergent formulator will have no difficulty in deciding which ingredients should be included in the slurry and which should not.

Particulate detergent compositions of the invention preferably have a bulk density of at least 400 g/l, more preferably at least 500 g/l.

Especially preferred compositions have bulk densities of at least 650 g/litre, more preferably at least 700 g/litre.

Such powders may be prepared either by post-tower densification of spray-dried powder, or by wholly non-tower methods such as dry mixing and granulation; in both cases a high-speed mixer/granulator may advantageously be used. Processes using high-speed mixer/granulators are disclosed, for example, in EP 340 013A, EP 367 339A, EP 390 251A and EP 420 317A (Unilever).

EXAMPLES

The invention is further illustrated by the following non-limiting Examples, in which parts and percentages are by weight unless otherwise stated. Throughout the Examples * denotes a Trade Mark.

Polymers

The polymer in accordance with the invention used (Polymer 1) was a water-soluble sulphonated polyester of terephthalic acid, isophthalic acid, sulphoisophthalic acid and ethylene glycol having the following approximate composition:

diacidic monomer comprising approximately 77 mole % terephthalate, 3.7 mole % isophthalate, 18.2 mole % sulphoisophthalate; ratio of OH groups ex ethylene glycol to COOH groups ex diacid monomers approximately 1.22; number average molecular weight, by GPC in tetrahydrofuran at 25.degree. C. with calibration against polystyrene standards, 534; weight average molecular weight 1667; sulphur content 2.4 wt %; hydroxyl group content approximately 1.4-1.5 per kg polyester.

For comparative purposes, the following commercially available polymers were used:

Polymer A: Sokalan (Trade Mark) HP22 ex BASF, a graft copolymer of polyethylene glycol and polyvinyl acetate. Polymer B: Repel-O-Tex (Trade Mark) ex Rhone-Poulenc, a PET/POET polymer, used in the form of a granule (50% wt % polymer, 50 wt % sodium sulphate).

EXAMPLE 1

Phosphate-built particulate detergent compositions were prepared to the following general formulation, using spray-drying and postdosing techniques:

______________________________________Na linear alkylbenzene sulphonate 25.00Zeolite 1.17Sodium tripolyphosphate 21.68Sodium silicate 5.00Calcium carbonate 10.00Sodium sulphate 21.24Sodium carboxymethylcellulose 0.70Fluorescer 0.01Acrylic/maleic copolymer (Sokalan* CP5) 1.80Perfume 0.25Protease (Savinase* 6T) 0.20Lipase (Lipolase* 100T) 0.05Amylase (Termamyl* 60T) 0.08Antifoam (silicone oil/silica) 0.01Soil release polymer see belowMoisture and impurities to 100.00______________________________________

The formulations had a bulk density of 420-440 g/litre and a 1 wt % aqueous solution pH in demineralised water at 25.degree. C. of 9.7-9.8.

Soil release and detergency on knitted polyester test cloths stained with Oilsol Blue dye/olive oil, were assessed in the tergotometer at two different product dosages, using the following wash regimes:

______________________________________ 3.8 g/l 1.3 g/l______________________________________Water hardness 25:3 Ca:Mg 15:3 Ca:MgpH 8.45 8.22Temperature 28.degree. C.Soak/wash time 30 min soak/10 min washPrewashes 5Replicates 2______________________________________

Detergency was assessed by measuring reflectance before and after washing using Micromatch (Trade Mark) apparatus. The differences (.DELTA.R 580*) are shown in the following Table:

______________________________________Polymer % 3.8 g/l 1.3 g/l______________________________________None 0 32.68 22.94Polymer 1 0.5 57.29 63.02Polymer A 1.0 50.63 27.96Polymer B 0.5 52.05 50.41______________________________________

Stain removal was also assessed visually by an experienced panel of five people. The results, expressed on a scale of 1 (heavy staining, initial stain) to 10 (complete removal), were as follows:

______________________________________Polymer % 3.8 g/l 1.3 g/l______________________________________Initial -- 1 1None 0 3 3Polymer 1 0.5 10 10Polymer A 1.0 6 4Polymer B 0.5 8 8______________________________________

EXAMPLE 2

Further phosphate-built particulate detergent compositions were prepared to the following general formulation, using spray-drying and postdosing techniques:

______________________________________Na linear alkylbenzene sulphonate 25.00Sodium tripolyphosphate 22.50Sodium silicate 5.00Sodium sulphate 28.90Sodium carboxymethylcellulose 0.70Acrylic/maleic copolymer (Sokalan* CP5) 2.00Sodium carbonate 2.00Fluorescer speckles 1.00Citric acid (anhydrous) 3.00Protease (Opticlean* M375) 0.784Lipase (Lipolase* 100T) 0.253Antifoam (silicone oil/silica) 0.04Perfume 0.33Soil release polymer see belowMoisture and impurities to 100.00______________________________________

The formulations had a bulk density of 370-430 g/litre and a 1 wt % aqueous solution pH in demineralised water at 25.degree. C. of 9.7-9.8.

Detergency was assessed, as in Example 1, by measuring reflectance before and after washing using Micromatch (Trade Mark) apparatus. The differences (.DELTA.R 580*) are shown in the following Table:

______________________________________Polymer % 3.8 g/l 1.3 g/l______________________________________None 0 30.34 38.56Polymer 1 0.25 57.84 60.67Polymer A 1.0 53.23 59.48Polymer B 0.25 53.71 61.77Polymer B 0.35 54.50 58.53______________________________________

Soil release properties were also assessed at a product dosage of 1.3 g/l by measuring relectance after a first wash and again after a second wash. The wash regime in the tergotometer was as follows:

______________________________________Test cloth Knitted polyesterStain Oilsol Violet/olive oilWater hardness 21:6 Ca:MgTemperature 28.degree. C.Prewashes noneSoak/wash time 30 min soak/10 min washRinse time 2 .times. 2 min______________________________________ Results ______________________________________ R 580*Polymer % Wash 1 Wash 2 Difference______________________________________None 0 42.30 44.49 2.19 ) 2.70 43.34 46.55 3.21 )1 1.0 46.75 58.31 11.56 ) 12.99 56.05 70.47 14.42 )B 1.0 50.45 60.52 10.07 ) 10.12 45.58 55.75 10.17 )______________________________________

EXAMPLE 3

An example of a phosphate-built non-bleaching high bulk density particulate detergent composition containing soil release polymer of the invention is as follows:

______________________________________Na LAS.sup.1 28.66Na PAS.sup.2 2.88Nonionic 9EO --Zeolite 18.84Na tripolyphosphate 29.69Na carbonate --Na bicarbonate 6.26Na silicate --SCMC 0.78Fluorescer 0.01Copolymer (Sokalan* CP5) 1.93Protease (Savinase* 6T) 0.32Lipase (Lipolase* 100T) 0.08Amylase (Termamyl* 60T) 0.14Soil release polymer 0.50Perfume 0.40Moisture and impurities to 100 wt %Bulk density (g/litre) 780-820______________________________________ .sup.1 Sodium linear alkylbenzene sulphonate .sup.2 Sodium primary alcohol sulphate

The composition is of low solution pH (9.7-9.8) and is especially suitable for washing delicate fabrics.

EXAMPLE 4

A further example of a high bulk density non- bleaching phosphate-built powder of low solution pH in accordance with the invention, suitable for washing delicate fabrics, is as follows:

______________________________________Na LAS 6.50Nonionic 6/7EO 4.00Soap 4.30Na tripolyphosphate 29.17Na silicate 10.00SCMC 0.43Polyvinyl pyrrolidone 0.95Na sulphate 17.00Na carbonate (heavy) 6.00Ammonium sulphate 2.00Citric acid 2.25Na metasilicate 2.00Amorphous aluminosilicate 1.12Protease (Savinase* 6T) 0.20Lipase (Lipolase* 100T) 0.05Amylase (Termamyl* 60T) 0.25Cellulase (Celluzyme* 0.7T) 0.40Soil release polymer 0.55Perfume 0.40Moisture and impurities to 100.00______________________________________

The bulk density of this formulation is 700 g/litre and the 1 wt % aqueous solution pH in demineralised water is 9.7-9.8.

Claims

1. A non-bleaching laundry detergent composition suitable for washing delicate fabrics, having a 1 wt % aqueous solution pH in demineralised water at 25.degree. C. not exceeding 10 and comprising:

(a) from 2 to 50 wt % of an organic surfactant system comprising one or more anionic, nonionic, cationic, amphoteric or zwitterionic surfactants,

(b) from 0 to 80 wt % of a builder component comprising one or more inorganic or organic detergency builders,

(c) a soil release effective amount of a water-soluble or water-dispersible non-end-capped sulphonated polyester consisting essentially of monomer units of

(i) an unsulphonated aromatic diacidic monomer (A),

(ii) a sulphonated aromatic diacidic monomer (SA)

(iii) optionally a hydroxylated aromatic or aliphatic diacidic monomer (HA), in an amount replacing up to 50 mole % of (A) and/or (SA),

(iv) a polyol (P) selected from ethylene glycol, propylene glycol, isopropylene glycol, glycerol, 1,2,4-butanetriol and 1,2,3-butanetriol, and oligomers of these having from 1 to 8 monomer units, the polyester having a sulphur content within the range of from 0.5 to 10 wt %;

(d) optionally other detergent ingredients to 100 wt %.

2. A detergent composition as claimed in claim 1, which comprises from 0.01 to 10 wt % of the polyester (c).

3. A detergent composition as claimed in claim 1, which comprises from 0.1 to 5 wt % of the polyester (c).

4. A detergent composition as claimed in claim 1, wherein the 1 wt % aqueous solution pH in demineralised water at 25.degree. C. is within the range of from 9.5 to 10.

5. A detergent composition as claimed in claim 1, wherein the organic surfactant system comprises an anionic surfactant selected from the group consisting of primary alkyl sulphate, alkyl ether sulphate, alkylbenzene sulphonate and mixtures thereof, optionally in combination with a nonionic surfactant.

6. A detergent composition as claimed in claim 1, which comprises no more than 0.1 wt % of fluorescer.

7. A detergent composition as claimed in claim 1, which further comprises a polycarboxylate polymer selected from polyacrylates and acrylic/maleic copolymers.

8. A detergent composition as claimed in claim 1, which further comprises a polymer capable of inhibiting dye transfer.

9. A detergent composition as claimed in claim 8, wherein the polymer capable of inhibiting dye transfer comprises polyvinyl pyrrolidone.

10. A detergent composition as claimed in claim 1, which comprises an enzyme system comprising at least two different enzymes selected from the group consisting of proteases, lipases, amylases and cellulases.

11. A detergent composition as claimed in claim 1, which further comprises a sequestrant for di- and polyvalent metals.

12. A detergent composition as claimed in claim 1, which is particulate.