AU615740B2

AU615740B2 - Detergent compositions

Info

Publication number: AU615740B2
Application number: AU33989/89A
Authority: AU
Inventors: Appaya Raghunath Naik
Original assignee: Unilever PLC
Current assignee: Unilever PLC
Priority date: 1988-05-06
Filing date: 1989-05-04
Publication date: 1991-10-10
Anticipated expiration: 2009-05-04
Also published as: ES2056215T5; DE68917195T3; ES2056215T3; EP0341071A3; ZA893327B; JP2664474B2; BR8902111A; CA1335876C; EP0341071B2; AU3398989A; EP0341071B1; DE68917195D1; EP0341071A2; GB8810820D0; JPH01318089A; DE68917195T2

Description

r T L. m

AUSTRALIA

PATENTS ACT 1952 COMPLETE SPECIFICATION Form

(ORIGINAL)

FOR OFFICE USE Short Title: Int. Cl: Application Number: Lodged: Complete Specification-Lodged: Accepted: Lapsed: Published: Priority: Related Art: TO BE COMPLETED BY APPLICANT Name of Applicant: Address of Applicant: UNILEVER PLC UNILEVER HOUSE

BLACKFRIARS

LONDON EC4

ENGLAND

Actual Inventor: Address for Service: GRIFFITH HACK CO., 601 St. Kilda Road, Melbourne, Victoria 3004, Australia.

Complete Specification for the invention entitled: DETERGENT COMPOSITIONS The following statement is a full description of this irnvention including the best method of performing it known to mei:- 1A- C.3242 DETERGENT COMPOSITIONS 9 TECHNICAL FIELD 5 The present invention relates to novel detergent Scompositions and especially, but not exclusively, to foaming liquid compositions useful for light-duty c applications such as manual dishwashing. The compositions may also have use for fabric washing, S 10 cleaning carpets and as shampoos.

DESCRIPTION OF THE PRIOR ART Light-duty liquid detergent compositions such as are suitable for use in washing dishes are well known. Many commercially-available formulations are based on a sulphate or sulphonate-type anionic detergent, especially alkyl sulphate, alkyl benzene sulphonate and alkane sulphonate, in conjunction with an alkyl polyethoxy sulphate (alkyl ether sulphate). The sulphonate-type detergent generally predominates.

The use of conventional dishwashing liquids based on alkyl benzene sulphonate/alkyl ether sulphate, or alkyl

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I

V

I 10

I.

FI

e.e i

C

I K

CC

it 2 C.3242 sulphate/alkyl ether sulphate has been found to have a deleterious effect on the hand condition of users, Mildness in detergent products, particularly in washing-up liquids, has hence become a desirable quality.

Alkyl mono- and poly-glycosides are known and have been disclosed in a number of prior art patents and literature publications. For example Boettner (US3219656) discusses the utility of alkyl mono-glycosides as foam stabilisers for anionic and nonionic surfactants.

Lew (US 3772269) discloses that decyl glucoside containing less than 1.6 glucose units acts as a good foamer.

Several Procter and Gamble disclosures (eg EP 0 070 074, EP 0 070 075 and EP 0 070 076) discuss the utility of alkylpolyglucosides having greater than 1.5 glucose units in detergent compositions. Henkel (EP 216 301 A) disclose the beneficial use of alkyl glycosides having from 1 to 1.4 glucose units which are incorporated in dishwashing liquids comprising ether sulphate and ethanolamide.

SUMMARY OF THE INVENTION The present invention relates to safe, mild liquid detergents with a good foam stability and a good cleansing ability based upon alkyl polyglycosides. The invention aims to provide novel, high-foaming nonionic-based liquid detergents comprising an alkyl polyglycoside. It is a further aim to provide a mild, ecologically safe liquid detergent.

Accordingly, the present invention relates to an aqueous liquid detergent composition comprising: a C 8

-C

18 alkyl polyglyooside surfactant having an average degree of polymerisation of from 1 to 3; C- T IP I P 3 C.3242 an anionic surfactant; a surface-active betaine and/or amine oxide; and optionally, an ethanolamide; wherein the amount of anioniz surfactant is not greater than times (on a molar basis) the level of betaine and/or amine oxid3 and wherein the total of betaine and amine oxide is at least 12wt% of the total active while the total of betaine, amine oxide and, if present, ethanolamide is not more than 30wt% of the total active.

'i 15 DESCRIPTION OF PREFERRED EMBODIMENTS Alkyl Polyglycoside e Alkyl polyglycosides, though nonionic in nature, differ from conventional ethoxylated nonionics such as alkyl ethoxylates or alkylphenol ethoxylates in having a different type of hydrophilic group and in consequence exhibit different physical, chemical and hence functional properties compared to conventional ethoxylated nonionics.

25 For example, ethoxylates are low melting solids or liquids at room temperature, are completely miscible in non-polar solvents and their aqueous solutions have cloud points.

In comparison, alkyl polyglycosides are high melting solids, sparingly soluble in non-polar solvents and their aqueous solutios do not show cloud points. Alkyl polyglycosides also generally give lower surface tensions and give a more stable foam compared to comparable, conventional nonionics. Alkyl polyglycosides are also prepared by different routes and can be produced entirely based on natural raw materials. Hence the compounds and compooitions made therewith can be expected to be biologically safer and more acceptable than conventional I'T V S C fl, 4 C.3242 0 0.

*0 0t

H

0* *0 0**0 0* nonionics and compositions containing them. Impurities present will also differ from conventional nonionics.

Alkyl polyglycosides may be manufactured by the Fischer glycoxidation of a detergent alcohol, eg Cg-C 18 Alcohol "glucose" catalyst ROGx (ROH) (G) Specification of the ROG product depends on control of the ratios of the reactants. A product will be a ratio of, eg ROG 1

:ROG

2

:ROG

3 The alkyl polyglycosides used in the present invention have a hydrophobic group containing approximately 8 to 20 carbon atoms, preferably about 10 to about 16, most preferably from 12 to 14, and a polysaccharide hydrophilic group containing from about 1 to about 3, preferably 1 to 1.5, most preferably 1.2 to 1.4 saccharide units on average. The saccharide unit may be, for example, a galactoside, glucoside, fructoside or glycuiyl. Mixtures thereof may be used.

Preferred alkyl polyglycosides are APG 500 and APG 550 from Horizon (APG is a trademark). APG 500 has an average degree of polymerisation of 1.4, APG 550 of 1.8. US 4 599 188 (Llenado) gives further description and characterisation of alkyl polyglycosides.

The alkyl polyglycoside is preferably the major active component and may, for example, be present at from to 60 wt% of the total active.

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I

I I r 5 C.3242 Anionic Sur'actant The co-active anionic surfactant used according to the present invention may be of the sulphate or sulphonate type, or a mixture thereof. The sulphates may be conventional anionic synthetic detergents, and may be sulphuric acid half esters of either alkanols (ie where n 0),or ethoxylated alkanols (ie, where n 1-40).

Suitable sulphates are from the linear, branched, primary i 10 or secondary alcohols, with or without ethoxylation.

Preferred alcohols are: i the linear primary alcohols having 10-14 carbon atoms, which, if ethoxylated, have up to 15 12 mols ethylene oxide per mol of alcohol; (ii) the mainly straight-chain primary alcohols having 10-15 carbon atoms and about 25% 2-methyl I .branching, which, if ethoxylated, have up to 12 mols ethylene oxide per mol of alcohol; (iii) the random secondary alcohols having 11-15 carbon atoms and 7-30 mols ethylene oxide per mol of alcohol.

Primary alcohols with substantial branching may be used.

The preferred cations which neutralise the anionic surfactant are sodium and ammonium, and the latter sulphates can be an aid to hydrotroping of the liquid compositions of the invention.

The sulphonates may be those conventionally used, including linear alkylbenzene sulphonate, secondary alkyl sulphonate and alpha olefin sulphonate.

The amount of anionic surfactant is preferably at "A4/ least 15wt% of the total detergent ictive.

w' I~ L -I 6 C.3242 Amine Oxide/Betaine The third essential feature of the present invention is the presence of an amine oxide or a betaine as a lather booster.

It is preferred to avoid using substantial amounts of these, especially amine oxides, for the sake of economy 4 and consequent cost effectiveness. Preferably then the amount of amine oxide is not more than 10% by weight of the active detergent mixture. Preferably the amount of betaine is at least 10% but not more than 30% by weight of vi this mixture. The total amount of amine oxide and betaine is from 12 to 30% by weight of the active detergent 15 mixture. The lather booster is preferably present at from 2 to 6% by weight of the total composition, It is preferred to use betaines alone.

CH CO 7 and aSuitable betaine include simple btaines of formula: 320 brahed alkyl group t may be a lauryl group r a R- CN--CH 2

CO

2 25 R and amido betaines of formula:

I

R CONH CH 2

CH

2

CH

2 N C 2 C~2 £7 In both formulae R is a C 8 to C 18 straight or brarched alkyl group. It may be a lauryl group or a ~r c ie I i 7 C.3242 middle cut coconut alkyl group. R 6 and R 7 are each C 1 to

C

3 alkyl or C 1 to C 3 hydroxyalkyl. Examples of sulphobetaines have the above formulae with -CO2CO 2 replaced by:

S

OH

-(CH

2 SO or -CH---CHSH SO 2 3 3 2 2 3 A suitable siimple betaine is Empigen BB from Albright Wilson. It has the formula quoted above in which R is I C12 to C14 alkyl, derived from coconut, and R 6 and R 7 are i both methyl. Also preferred is Tego L7 from Goldschmidt, which has i whole coconut alkyl group.

S Suitable amine oxides have the formula: S

S

*R R 6

R

7 N- 0 20 wherein R is a straight- or branched-chain C 8 to C 18 alkyl group and R 6 and R 7 are each C 1 to C 3 alkyl, or C 1 to C 3 hydroxyalkyl. A suitable amine oxide is Empigen OB from SAlbright Wilson. In it R is middle-cut coconut alkyl and R 6 and R 7 are both methyl.

Additional Ingredients The compositions according to the present invention may include other conventional ingredients such as minor amounts of builders, urea, sodium or ammonium chloride, corrosion inhibitors, colourings and perfumes.

Conventional foam boosters such as ethanolamides may be included.

The presence of ethanolamide is optional. If present, the total level of betaine and/or amine oxide and I 8 C.3242 ehtanolamide is from 12 to 30 wt% of the total active. A preferred ethanolamide is Empilan LME (Albright Wilson).

The compositions according to the present invention ji 5 are of particular use as light duty liquid detergent compositions for manual dishwashing.

The term "dishes" as used herein means any utensils involved in food preparation or consumption which maybe requixed to be washed to free them from food particles and Sother food residues, greases, proteins, starches, gums dyes, oils and burnt organic residues.

i Typical compositions for manual dishwashing comprise from about 5 to about 60 wt%, preferably about 10 to about i 40 wt% of the mixture of active components hereinbefore i described, the balance comprising water and solvents.

S S The compositions according to the present invention are mild and environmentally safe. They exhibit good foam characteristics.

i The invention will now be described in more detail by i the following Examples.

EXAMPLES

*see The foaming performance and mildness of various aqueous formulations were compared. Those formulations falling within the scope of the present application were compared with comparable compositions outside the scope.

Foaming performance was assessed by means of a modified Schlachter-Dierkes test based on the principle described in Fette und Seifen 1951, 53, 207. A 100 ml aqueous solution of each material tested, having a 9 C.3242 l C

C~

*e oi.

Ce

C.

concentration of 0.04% active detergent in 24°H water (French hardness) at 45*C was rapidly oscillated using a vertically oscillating perforated disc within a graduated cylinder. After the initial generation of foam, increments (0.2 g) of soil (9.5 parts commercial cooking fat, 0.25 parts oleic acid, 0.25 parts stearic acid and parts wheat starch in 120 parts water) were added at second rvals (10 seconds' mild agitation and seconds' rest) until the foam collapsed. The result was recorded as the number of soil increments (NSI score): a score difference of 6 or less is generally regarded as insignificant. Each result was typically the average of 3 or 4 runs.

Several in-vitro and in-vivo methods for evaluating protein denaturation potency of surfactants and their mixtures have been reported (see Miyazowa et al, Int J Cos Sci 6 33-46 1984, and the references cited therein). One such method is the study of interaction of detergents with 20 acid phosphatase enzyme either from skin (Prottey et al, Int J Cos Sci 6 263-273 1984) or from Wheatgerm (Tanaka et al, Anal Biochem 66 489-498 1975).

In vivo mildness of formulations can be assessed using a flex wash test. In this test neat products were rubbed on the forearm of panellists and rinsed. The process was repeated four times n day for five days and the level or erythema developed was assessed by trained assessors.

A comparison of wheatgerm acid phosphatase (WGAP) test and flex wash test results indicated that formulations giving less than 50% enzyme inhibition under the test conditions are substantially mild; any mildiess differences between products giving <40% inhibition do not show any detectable mildness differences in flex wash

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in, I I 10 C.3242 test, in3dicating that the enzyme test is very sensitive and that in a real life situation there is a threshold level of protein denaturation below which all actives and products are indistinguishably mild. The results of the WGAP test are expressed as percentage inhibition (ie, 100% minus percentage activity remaining). Water gave no inhibition at all, ie 100% of activity remained.

Materials Used APG APG 500 or APG 550 from Horizon Chemicals.

Both have C12-C14 alkyl groups. Average degree of polymerisation of 1.4 and 1.8 respectively.

PAS Dobanol 23-S (Shell) Betaine Empigen BB (Albright Wilson) Amine Oxide Empigen OB (Albright Wilson) LME Emplilan LME (Albright Wilson) The varying amounts of ingredients used in the compositions tested are shown below as a percentage of the total weight of the composition.

S S a a a S.

a a a a a a S a a a a. S S a.

a a a a a a aa a a.

C. 3242 11 'Example Numiber Plunger Test Product 24-H, 45-C, 0.4% AD 1 2 3 4 6 7 8 9

A

B

C

D

19/614/5 ,221616 22/ 616 18/8/8 18/818 22/81614 9/9/ 818 919,/fG18 18/8/8

APG

A-PG

APG

A-PG

APG

500 /PAS/Betaine/LME 500/PAS/,Betaine 500/P1P---,Ainne oxide 500 /PAS/Betajne 500IPASIlAmine oxide 500 /PAS /AO/LME 5QOIDobanol 23-3S/PAS/Betaine 500,/Dobanol 9 1-8EOIPAS/Betaine 550,/PAS/Betaine 37 37 39 39 29 22/12 18/8/8 22/814 22/12 500 /Betaine 500/PAS/LME 50 0/PAS/Betaine 500/PAS 12 -C.3242 The foam tests show that compositions falling within the scope of the invention perform better than those outside B and D) Furthermore, APG 500 performs better than APG 550.

Thoi following enzyme inhibition tests were performed; Enzyme Product Inhibition 19/6/4/5 Dobanol 91-BEO/P;hS/Betaine/LME 4 19/6/4/5 APG 500/PAS/Betaine/LME 4 c~ ~in the WGAP test, APG and nonionic formulations give similar low enzyme inhibition, and hence both have similar mildness.

L'

Claims

1. An aqueous liquid detergent composition comprising: a C-C18 alkyl polyglycoside surfactant having an average degree of polymerisation of from 1 to 3; V an anionic surfactant; a surface-active betaine and/or amine oxide; and optionally, an ethanolamide; *c wherein the amount of anionic su,-actant is not greater than C 1.5 times (on a molar basis) the level of betaine and/or amine oxide and wherein the total of betaine and amine oxide is ai least 12wt% of the total active while the total of betaine, amine oxide and, if present, ethanolamide is not more than 30wt% of the total active.

2. A composition as claimed in claim 1, wherein the alkyl polyglycoside has an average degree of polymerisation of from 1 to 1.4.

3. A composition as claimed in claim I or claim 2, wherein the anionic surfactant is a primary alkyl sulphate. C 'ss; I m ~L 14

4. A composition as claimed in any one of the claims 1 to 3, wherein a betaine alone is used as a lather booster.

A composition according to any one of claims 1 to 4 wherein a nonionic active is also present.

6. A composition according to any one of claims 1 to wherein at least 10wt% of a betaine is present.

7. A composition according to any one of claims 1 to 6 wherein at least 15wt% of anionic surfactant is present.

8. A composition according to any one of claims 1 to 7 wherein the amount by weight of anionic active is at least equal to the total by weight of betaine and amine oxide. o.

9. An aqueous liquid detergent composition as claimed in claim 1 comprising: *o from 50 to 60wt% total active of: an alkyl polyglycoside having an average degree of polymerisation of from 1 to 1.4; from 15 to 20wt% of a primary alkyl sulphate; from 10 to 15wt% of a betaine; from 10 to 15wt% of an ethanolamide. DATED THIS 24TH DAY OF JULY 1991 UNILEVER PLC By its Patent Attorneys: GRIFFITH HACK CO. Fellows Institute of Patent Attorneys of Australia.