CA2040202A1 - Enzyme stabilizing composition and stabilized enzyme containing built detergent compositions - Google Patents

Abstract

ENZYME STABILIZING COMPOSITION AND
STABILIZED ENZYME CONTAINING BUILT
DETERGENT COMPOSITIONS

ABSTRACT OF THE DISCLOSURE

A three component enzyme stabilization system including boric acid, citric acid and calcium ions helps maintain the enzyme activity of aqueous built detergent compositions in accelerated aging (multiple freeze-thaw cycles). The preferred detergent compositions are "softergents" and also include a clay softener, a mixture of anionic, nonionic and amphoteric surfactants, and detergent builder(s).

Description

209020~ ~ ~
l~ IR-1117F
1l1 -- ¦ EN~YME STABILIZING COMPOSITION AND
i' ST-ABILIZED ENZYME CONTAINING BUILT
DETERGENT COMPOSITIONS

Backqround of the Invention This invention relates to stable, built, enzyme~
containing liquid detergent compositions suitable for laundry or pre-soak formulations. More particularly, the invention relateg to aqueous enzyme-containing liquid detergent compositions which contain one or more detergent builders and which are l characterized by bei~g physically stable, homogeneous liquid compositions, having improved enzyme stability. The invention also relates to the novel stabilized enzyme preparation useful a laundry additive, as well as to the novel enzyme stabilizatio~
system, per se.
l The formulation of stabilized enzyme-containing liquid 1 detergent compo~itions has been the focus of much attention in the prior art. The de~irability of incorporating enzyme~ into detergent compositions is primarily due to the effectiveness of proteolytic and amylolytic enzymes in decomposing proteinaceous and starch materials found on soiled fabrics, thereby facilitating the removal of stains, such as, gravy stains, blood i1 stains, chocolate stains and the like during laundering.
However, enzymatic materials suitable for laundry compo3itions, particularly proteolytic enzymes, are relatively expensive.
Indeed, they generally are among the most expen~ive ingredients in a typical commercial liquid detergent composition, even though they are present in relatively minor amounts. Moreover, enzymes are known to be unstable in aqueous compositions~ It 15 for this ~1 l ~ .

~ -~ on tl~t ,~n exces~ of en~iyu~ g~3n~rally r~ llquld d~rgont f~:rmulatlvn~ to compens~ e for the~ oxpocted lo~ ~f enzyme activ.ity àul ing prolonged p~riodo c; ~ ~torAg~.
P.qoordingly, tha pl lo~ hrt 1~1 r~pl-lte w~ th 4 ~lgg-l~tic-n~ f or S ~t~blliæ~ng en2yrn~ aontlaining liquld d~t~ 0:rlt oompc-sition~, o.nd in p~l~ticul~r by th~l u~e o~ v~lrlou~ m~t~riRll0 whiah l-~o lncorporAt~ad into t:ho com~o~lition t~ ~unction ~ snzym~
~t~bili~-r h .
In l;he asue o~ llquid dat~s g~nt c:o~ c~ition~ ~ontAininy 19 a bulld~r, the problem of ~nzym~ Ln~stability i0 part.l~ul~rly ~c~uk~. Prim~rily t.hl~ 6~ U~alO de~g~-nt bulld~xfl h~vo ~
d~t~biliainy ~oct on ~ns~,~mo~, ~v~n ln ooml~sE~ition~ aon~aining enzym~ ~t~bi3.i~r~ whlah ar~l othsrwL~M ~f f ~ iv- ln unbllilt ~ormul~tion~. Moreovor, th~ l.nc20r~0rAtisn o~E a bulldor into liqul~ d~t~rslont ao~positio~ o~o0 ~n additlon~l problom, namely, tho ~bility t.o fO~U~ t4bl~ ~ingle-pha-~ aoJnpo~ition~ ths ~olu~ility o~ ~odium trlpolypho~ph~t~ r ~x~m3?1O, boing rel~tiv-ly llmi~-~d in 6uaueou~ s; ompo~ltion~ nd ~ilpeciAlly in tho pro~noe of ,nlonLa Ar~d rlonlonla da~r51~ntu.
2V Att~!m~tD to ~tablliza enzymo nativit;y in a~uoou~ m~dla ~r~ axt~n~iv-!ly do~arl.bod ln th~ pAtont lltor.-.tur~l. Amonq tho ~pprol~a}le~ to th- prokll~m of onzymo l-tn~ ion ha~ b~n tho uso of ~r~riou~ or~an~ra mo,t~rl~ls, ~uah a~ Alaohol~ polyol~, acl~d~ tor~ ~nd ougax- whlah ~ra 6~1d to h~lv~ t~billzin~
o~at upon ~n~:~m~. Wat~lr-~olu~ lum u~lt~ and bc~ n aompound~ h~vo al-o boon u~d ~o ~tnb~llz~ or~ym~ aonl~o~i'cion~.
Thu~, for ox-.mpl~, U.~. P~ltont 4,253,5413 tc~ G~uilb-rt ~k~ 'co provlde en~yn~ 0tAbll ~ t~r by ~dding ~n An ti-o~:idant and ~ polyol to h-aUOOU~il d~torg~nt ~om~o~it~on~- U.~. ~a~nt 4,111,~55 to ~srr~t, ~t Al. ua~l a aomb4neltlon of ~rom ~bout ~.V5 to about 2~02~ 1 1.5% by weight of a polyacid capable of forming water-soluble Ca-complexes, such as citric acid, and calcium ion in an amount of Il from 0.5 to 15 millimoles per liter as an enzyme stabilizer.
- ¦! U.S. Patent 4,287,082-to Tolfo, et al. discloses i homogeneous enzyme-containing liquid detergents characterized by the presence of a C1o-C16 saturated fatty acid, calcium ion and a Cl-C3 short chain monocarboxylic acid or salt thereof.
! u.s. Patent 4,318,818 to Letton, et al. also describes an enzyme composition which is stabilized by calcium ion and a jl short cha1n length carboxylic acid salt. A polyacid may also be ¦¦ present in the compositions of Letton, et al. a~ well as those of Tolfo, et al.
In U.K. Patent Application G.B. 2,079,305, published January 20, 1982 and Canadian Patent 1,092,036, there i~
disclosed an aqueous built enzyme-containing liquid detergent composition which i8 ~tabilized by a mixture of a polyol and boric acid.
In U.S. Patent 4,532,064, there i8 disclosed an aqueous enzyme-containing liquid detergent composition containing an enzyme stabilizing mixture consisting of certain dicarboxylic acids and borax. The dicarboxylic acids of the formula COOH-¦ (C~OH)a-(cH2)b-(c~oH)c-~cH2)d-cooH in which a~ b, c, d axe whole numbers from 0 to 4, the sum a+b+c+d - 0 to 4, or the alkali l metal, ammonium, alkanolamine or alkaline earth metal ~alts ~ thereof, are recommended as a substitute for a polyol such as glycerol in known enæyme stabilizing mixture~ consisting of glycerol and a boron compound. However, such dicarboxyl~c acid~
borax mixtures in common with the aforementioned mixtures of ! glycerine and borax provide only a modest stabilizing effect in !l 2 o :~ ~2 ~3 2 1 l Il unbuilt liquid detergent composition~, especially under freeæe-!~ thaw conditions.
¦ U.S. Patent 4,529,525 to Dormal, et al. discloses an - 11 unbuilt stabilized enzyme-contalning liquid detergent composition 1 comprising: (a) from about 5 to about 75~, by weight, of one or more non-soap detergent surface active agents selected from the group consisting of anionic, nonionic, cationic, ~npholytic and zwitterionic detergent compounds; (b) from about 0.1 to about 20 ¦ millimoles of calcium ion per liter of composition; (c~ from about 0.05 to about 5~, by weight, of an enzyme selected from the ~
group consisting of proteases, amylases and mixtures thereof; (d) ¦

! from about 0.1 to about 10%l by weight, of a stabilizing agent comprising (i) at least one water-soluble salt of a dicarboxylic acid represented by the formula (C~2)n(COOB)2 wherein n is an lS integer from 1 to 6; and/or (ii) at lea~t one wat~r-soluble ~alt of an unqaturated dicarboxylic acid selected from the group consisting of fumaric acid and maleic acid; (e) from about O to about 25%~ by weight, of a soap comprising a water-soluble salt ll of a saturated fatty acid having 10 to 18 carbon atoms in the alkyl chain; and (f) the halance water and optionally a ! sequestrant. This patent also illustrates two formulations containing sodium borate in place of a dicarboxylic acid of the , above for~ula. Sodium tartrate is also exemplified in ~pecific l formulations.
U.S. Patent 4,842,769 to Shulman, et al. discloses a stabilized fabric softening built, enzyme-containing liquid detergent composition comprising:
(a) from about 5 to 20%, by weight, of one or more ¦¦ surface active detergent compounds selected from the group !

~ i ,, _ . . . _ 2~2~2 consisting of anionic, nonionic and amphoter c detergent ~! compounds;
I (b) from about 5 to 30%, by weight, or one or more ~~ I builder salts selected from the group conRisting of alkali metal i tripolypho phates, alkali metal carbonate~, alkali metal nitrilotriacetates, and polyacetal carboxylates;
(c) from about 5 to 20%, by weight, of a swelling bentonite clay;
l (d) an effective amount of an enzyme or an enzyme j mixture selected from the group consisting of alkaline protease enzymes and alpha-amyla~e enzymes;
(e) an enzyme-~tabilizing system containing, based on the weight of the detergent composition, (i) from about 1 to 10%

I glycerine; (ii) from about 1 to 8% of a boron compound selected from the group consisting of boric acid, boric oxide, and alkal i metal borates and, (iii) from about 0.5 to 8% of a carboxylic acid compound selected from the group consisting of mono, di and/or polycarboxylic acids having 1 to 8 carbon atoms, and which i! may contain hydroxy or amino substituent~, and wat~r-soluble salts thereof; and (f) the balance comprising water and opti.onally perfumle and other adjuvants.

I The related U.S. Patents 4,537,706 and 4,537,707 to I Severson, Jr. each disclo~e heavy-duty liquid detergent compositions comprising, by weight:
(a) from about 10~ to about 50% of an anionic synthetic surfactant;
(b) from about 3% to about 30% of a C1o-C22 fatty acid;

! (c) from about 2% to about 15~ of a water-soluble detergency builder;

20 iO2~12 (d) from about 0.01% to about 5% of a proteolytic or amylolytic enzyme;
(e) from about 0.25% to about 10% of boric acid or a ~ 'I boron compound capable of formlnq boric acid in the composition;
(f) from about 1 to about 30 millimoles of calcium ion per liter of composition; and (g) from about 20~ to about 80% of water; and ~I in the ~707 patented composition !1 (h) from about 0.05% to about 5% of a water-soluble I formate. The compositions may also include various optional ingredients, including the known polyol enzyme stabilizer~. The polycarboxylates are disclosed as preferred builders and citrates lj as highly preferred builder materials. The formulations of ,¦ Exampl~ I of these patents include a polyacid, i.e. citric acid ! (anhydrous) in an amount of 4.0 weight~. The exemplified levels ¦¦ of boric acid range from 0.5 to 2.0~ and the exemplified calcium ¦ ion concentrations range from 9.65 to 15.6 millimoles per liter.
In our commonly assigned copending application Serial No. 07/255,817 filed October 7, 1988, titled ~EAVY DUTY F~BRIC
, SOFTENING LAUNDRY DETERGENT COMPOSITION, the disclosure of which j~ is incorporated herein in its entirety by reference, a highly advantageous "softergent" liquid composition based on a combination of anionic and nonionic surfactants and a certain jl type of amphoteric surfactant, inorganic builder, bentonite and 1 water is disclosed. These compositions may, and preferably do, also include enzyme(s) and enzyme stabilization system. The enzyme stabilizer system includes 0.5 to 5% of a mixture of dibasic acid of 4 to 6 carbon atoms each, 1 to 3~ of boric acid and 0.1 to 0.5~ of a sGurce of calcium ion. However, as will he shown in the examples which follow, the stabilizing power of this Il l !l 2 ~ 2 I stabilization system is legs efficient than the ~tabilization system according to this invention.
l While many of the~e previously described formulation~
_ ¦ have been able to extend the us~ful life of the enzyme l component(s) under normal or slightly elevated temperatures, e.g.

i 90F, 100F or 110F (in Canadian Patent 1,092,036 enzyme stabilization was measured at about 133F to 140F), still further improvements are desired, e~pecially with regard to the l1 enzyme stabilization for enzyme containing composition~ subjected 1 to more severe storage conditions, such as freeze-thaw l conditions.
l . .
Summary of_the Invéntion The present invention provides a built liquid detergen~
l composition which contain~, on a weight ba~is, 1 (A) from about 5 to about 75% of one or more surface active detergent compounds, . (B) from about 5 to about 30~, of one or more detergency builders;
(C) from about 0.01 to about 5% of at least one enzyme;
2C I selected from the group consi~ting of proteases, amylases and mixtures thereof;
(D) an enzyme stabilization system which includes, ¦ (i) from ahout 0.25 to about lO~ of a boron compound ¦¦ selected from the group consisting of boric acid, boron oxide and 1 alkali metal borates;
(ii) from about 1 to about 3~ of an hydroxycarboxylic acid selected from the group consisting of aliphatic di- and tri-, carboxylic acids with from 1 to 4 hydroxyl groups and from 4 to 8carbon atoms; and 20~D2~2 I!
! `
(iii) a water soluble calcium salt in an amount ~ufficient to provide from about 18 to about 50 millimoles of l calcium ion per liter of the composition; and _ I (E) water.
1 In a preferred embodiment of the invention, the built i enzyme-containing liquid composition includes (A) from about 5 to about 30%, by weight, of a mixture of (a) non-soap anionic surface active detergent compound and (b) nonionic surface active detergent compound at an (a):(b) ratio, ll by weight, of from about 1:4 to about 10:1;
(B) from about 5 to about 25%, by weight, of at least ~¦ one detergency builder selected from the group consisting of i alkali metal polypho~phate~, alkali metal carbonates, alkali I metal nitrilotriacetates, polyacetal carboxylates, and mixtures thereof;
(C) from about 0.1 to about 3%, by weight, of a protease, amylase, or mixed protease-amylase enzyme system;
(D) an enzyme stabilization system containing l (i) from about 0.5 to about 8%, by weight, of boric acid, borlc oxide or alkali me~al borate;
(ii) from about 1.5 to about 2.5~, by weight, of '1 citric acid; and (iii) a water-soluble calcium salt ln an amount j sufficient to provide from about 22 to about 36 millimoles of i calcium ion per liter of the composition;
(E~ from a~out 5 to about 20~, by weight, of a clay softening agent; and (F) water, and optionally perfume and other adjuvants.
l In accordance with the process of the invention, laundering of stained and/or soiled materials i~ affected by ll 2~ 2 contacting such materials with an aqueous solution of the above-defined liquid d~tergent compositions.
Il The described liquid detergent is a commercially - 1¦ acceptable heavy duty laundry ~etergent, capable of , satisfactorily cleaning laundry items containing both oily and particulate soils. Additionally, the de~cribed compo~ition~ may be employed for the pre-treatment of badly soiled areas, Ruch as collars and cuffs, of items to be laundered.
l While the three component~ of the enzyme stabilization ; system are typically separately added to the aqueou~ built laundry detergent composition during the manufacture of the detergent composition, it is also possible to separately ¦
formulate a stabilized dry or aqueous en~yme preparation which I can be added as such during detergent manufacture or can be added I directly by the end user to the washing machine or to soiled ¦ fabrics. Similarly, the three-component stabilization system ¦ can be separately prepared in either dry form, e.g. powder or granules or as an aqueou~ solution and added directly during the 1 manufacture of the laundry detergent composition prior to the j addition thereto of the enzyme(~). Accordlngly, the present I invention also provides a stabilized enzyme preparation useful as a laundry additive containing either or both of protea~e and I amylaqe enzyme, and an enzyme stabilizing effective amount of an I enzyme stabilization ~ystem consisting e~sentially of (i) from !1 about 0.25 to about 10 parts by weight of boric acid, boron oxide or alkali metal borate; (ii) from about 1 to about 3 parts by weight of an hydroxypolycarboxylic acid having 2 or 3 carboxylic acid groups and 1 to 4 hydroxyl groups and containing from 4 to 8 ! carbon atoms and (iii) a water-soluble calcium salt in an amount to provide from about 18 to about 5~ millimoles calcium ion per 2~4~202 liter. The pre~ent invention also provides an enzyme stabilization system with the three components (i), (ii~ and ~iii) as defined immediately above.
I The present invention ls predicated upon the di~covery of a three component enzyme stabilizing system as herein defined which provides an enz~ne stabilizing effect to aqueous liquid ! detergent compositions superior to that which can be achieved ! with conventional enzyme stabilizers. The enzyme stabilizing 1 effect thus achieved reflects a 6ynergy among the three components as most clearly manifested by the results in accelerated aging tests, including repetitive freeze-thaw cycles as described hereinafter.

Detailed Description of the Invention ,l I. Enzyme Stabilization System , The enzyme stabilizing system of the invention is a Il mixture of (i) a boron compound selected from among boric acid, boric oxide and an alkali metal borate, particularly sodium borate, especially sodium tetraborate, e.g. borax (~a2BrO7 10H20), (ii~ an hydroxypolycarboxylic acid having from 4 ~ to 8 carbon atoms, preferably 4, 5 or 6 carbon atoms, two or three carboxyl (-COOH) groups and 1 to 4, preferably 2 or 3 hydroxyl (-OH) groups, and (lii) a water-soluble calcium salt capable of providing calcium (Ca++) ions in aqueous media.
,I The boron compound (i) is boric acid or a compound l capable of producing boric acid, such as boric oxide or a salt, such as sodium borate. Borax i~ readily available and i8 preferred.
The boric acid compound is used in an amount of from about 0.25% to about 10%, preferably from about 0.5~ to about 8%, ll l .1 ll l more preferably from about 1% to about 5%, such as 2%, 3% or 4%
by weight, of the total detergent composition.
l Citric acid is the preferred hydroxypolycarboxylic acid, - ! especially in view of its ready availability and its contribution 1 to improving the overall physical stability of the composition, i.e, prevent phase separation. However, other hydroxycarboxylic acids, such as malic acid, tartaric acid, isocitric acid, tricarballylic acid, trihydroxyglutaric acid and mucic acid, may l also be used. Lactic acid, which has only 3 carbon atom~, will 1 also provide enzyme stabilization; however, replacing e.g.
citric acid with an equal weight of lactic results in compositions which are physically unstable - i.e. undergo phase separation.
The acid is usually incorporated into the composition as the free acid (or hydrated free acid), but may also be added in the form of its salt, especially alkali metal salt. In fact, it is thought that under the preferred alkaline p~ conditions for the detergent compositions, the hydroxypolycarboxylic acid will be present in itR ionized (salt) state.
The hydroxypolycarboxylic acid is used in an amounk of from about 1% to about 3%, preferably from about 1~2 to 2.6%, by weight of the total detergent composition.
The level of calcium ion as component (iii) in the l detergent composition is from about 18 to about 50 millimoles, ~ preferably from about 22 to about 36 millimoleR, per liter of the composition. Suitable water-soluble calcium salts which can be used as a source of calcium ion include both inorganic and organic salts, such as calcium chloride, calcium acetate and l calcium formate. Calcium chloride is preferred. About 0.2%
CaCl2 corresponds to about 18 millimoles Ca++ per liter. A small il 2U~202 amount of calcium ion, generally from about 0.05 to about 0.4 jl millimole per liter, is often also present due to calcium in the I¦ enzyme preparation or water, but any such naturally present - 1I calcium ion will generally be ~n~ignificant to the added calcium 5 1l ion.
As will be shown in the examples to follow, the individual ingredients (i), (ii) and (iii) are usually separately I added in any convenient order durin~ the manufacture of the l aqueous built laundry detergent compositions. However, it may also be convenient in some cases to separately prepare a stabilized enzyme preparation which can then be directly added to the other ingredients of the laundry detergent composition. When used for this purpose, the stabilized enzyme compo~ition may be formulated as a free flowing dry mix, such a~ powder or granules, 1 containing up to about 20% by weight of water, or may be formulated as a concentrated aqueous solution. Furthermore, the aqueous stabilized enzyme preparation with or without any additional surface active agent, as required for stabilizing the Il composition, can also be used directly to assist in the 1 laundering proce~, for example, as a ~eparate additive for use in combination with an enzyme-free laundry detergent composition.
The enzyme preparation may be added directly to the washing machine, before, after, or simultaneously with a separately l prepared laundry detergent composition, or it may be used as a 1 presoak by using it dixectly on soiled laundry. The three components (i), (ii) and (iii) in this embodiment of the invention will generally comprise from about 5 to 75% of the total composition, preferably 10 to 60% of the total composition, the balance being the enzyme and aqueous carrier, usually water 30 ! which may contain a small amount of surface active agent, such as l 12 ~ ~02~2 the anionic, nonionic or amphoteric ~urface active aqents to be described below, for example, up to ahout 20%, preferably up to about 10~ of the stabilized aqueou6 enzyme composition.
I¦The three component s~abilizing system may also be ! separately prepared without the enzyme and added as such to the remaining ingredients of the aqueous built laundry detergent composition at any time pxior to the addition of the enzyme(s).

II. Enzyme I The alkaline proteolytic enzyme~ suitable for the 1 present compositions include the various commercial liquid anzyme preparations which have been adapted for use in detergent l compositions. Enzyme preparations in powdered form are also i useful although, as a general rule, less convenient for Il incorporation into the built liquid detergent composition~.
,I Thus, suitable liquid enzyme preparations include "Alcala~e,"
'Savinase,~, and "Esperase", all trademarked products 601d hy 'j Novo Industries, Copenhagen, Denmark, and "Maxatase," "Maxacal,"
and "AZ-Protea6e" sold by Gist-Brocades, Delft, The Netherlands.
l Among the suitable alpha-amylase liquid enzyme ~ preparations are those sold by Novo Industries and Gist-Brocade6 under the tradenames "Termamyl" and "Maxamyl," respectively.
"Esperase" is particularly pxeferred for the present compositions because of its optimized activity at the higher pH
¦I values corresponding to the built detergent compositions.
25 IMixtures of proteolytic and amylase enzymes can and often are used to a6si~t in removal of different types of stains.
The proteolytic enzyme and/or amylase enzyme will normally be present in the compositions in an effective amount in the range of from about 0.01% to about 5%, preferably from about 20~202 0.05% to about 2%, by weight o the composition. For the ; proteolytic enzymes, the suitable amounts will generally provide from about 0.005 to about 0.1, more preferably from about 0.01 to I about O.07 Anson units per gram of composition, depending on the use to which the composition will be applied. Generally, lower levels of amylase are required.
Lipolytic, cellulytic and carbohydroxylytic enzymes, all of which are also commercially available may also be employed.

, , III. Surface Active Detergent Compounds The preferred detergents for u~e in the present liquid compo~itions are the synthetic anionic detergent compounds, and ~I particularly alkyl polyethoxy sulfate. Other water Yoluble 'I anionic detergent compound, such a~ higher alkylbenzene Il sulfonates may also be pre~ent in the instant formulas, such as~
1 pota~sium salti and in some instances the ammonium or alka~ol- I
amine salts, however, it ha~ been found that the sodium ~alt i8 i Il highly preferred, which i8 al80 the ca~e with respect to the ,l alkyl polyethoxy sulfate detergent component. The alkylbenzene , sulfonate is one wherein the higher alkyl is of 12 to 15 carbon j atoms, preferably 13 carbon atoms. The alkyl polyethoxy sulfatel, ,I which also may be referred to as a sulfated polyethoxylated higher linear alcohol or the sulfated condensation product of a higher fatty alcohol and ethylene oxide or polyethoxylene glycol, Il ls one wherein the alkyl is of 10 to 1~ carbon atom~, preferably 1 12 to 15 carbon atoms, e.g. about 13 carbon atoms, and which includes 3 to 11 ethylene oxide groups, preferably 3 to 7, more ¦ preferably 3 to 5 and most preferably 3, or about 3 ethylene ! oxide groups on average. Mixtures of the alkyl polyethoxy sulfate and alkylbenzene sulfonate are often advantageous and can il .i Ii ~

2~x~2 be used at a ratio of alkylbenzene sulfonate to polyethoxy sulfate in the detergent mixture of from about 1:6 to 6:1 and l~ most preferably from about 1:4 to 4:1, by weight. At ratios - I above 5:1, the phy6ical stabil~y of the product may be adversely !l affected.
In suitable circum~tances other anionic detergentY, such as fatty alcohol sulfate~, paraffin sulfonates, olefin sulfonates, monoglyceride sulfates, sarcosinates and similarly l functioning detergents, preferably as the alkali metal, e.g.
so~ium salts, can be present, sometimes in partial replacement of ~! the previously mentioned synthetic organic detergents but ¦ usually, if present, in addition to such detergents. Normally, I the supplementing detergents will be sulfated or sulfonated il products (usually as the sodium ~alts~ and will contain long I chain (e.g. 8 to 20 carbon atoms) linear or fatty alkyl groups.
¦ In addition to any supplementing anionic synthetic ¦ organic detergents, there also may be present nonionic and amphoteric materials, like the Neodols ~ sold by Shell Chemical Company, which are condensation product~ of ethylene oxide and , higher fatty alcohols, e.g. Neodol ~ 23-6.5, which is a ¦ condensation product of a higher fatty alcohol of about 12 to 13 carbon atoms with about 6.5 moles of ethylene oxide.
Illustrations of the various detergents and classe~ of detergents ¦ mentioned may be found in the text Surface Active Agents, Vol.
1¦ II, by Schwartz, Perry and Berch (Interscience Publishers, 1958), the descriptions of which are incorporated herein by reference.
The nonionic detergents also include the polyethylene oxide condensate of l mol~ of alkyl phenol containing in the alkyl group from about 6 to 12 carbon atoms in a straight or branched chain configuration with about 5 to 30 moles of ethylene :` 2~0202 oxide, for example, nonyl phenol condensed with 9 moles of ethylene oxide; dodecyl phenol condensed with 15 moles of ethylene oxide; and dinonyl phenol condensed with 15 moles of jl ethylene oxide. Condensation ~roducts of the corresponding alkyl I .
5 1 thiophenol~ with 5 to 30 moles of ethylene oxide are also .
suitable.
Of the nonionic surfactants, those of the ethoxylated and mixed ethoxylated propyloxylated fatty alcohol type a~e l preferred. Examples of preferred nonionic surfactants include the condensation product of coconut fatty alcohol with about 6 I moles of ethylene oxide per mole of coconut fatty alcohol; the condensation product of tallow fatty alcohol with a~out 11 moles of ethylene oxide per mole of tallow fatty alcohol; the I¦ condensation product of a ~econdary fatty alcohol containing ,l about 11-15 carbon atoms with about 9 moles of ethylene oxide per ¦¦ mole of fatty alcohol and condensation products of more or less ¦ branched primary alcohols, whose branching is predominantly 2-i methyl, with from about 4 to 12 moles of ethylene oxide.
,. Especially preferred nonionics are represented by the , commercially well-known class of nonionic~ which are the reaction product of a higher linear alcohol and a mixture of ethylene and ,I propylene oxide~, containin~ a mixed chain of ethylene oxide and propylene oxide, terminated by a hydroxyl group. Examples ! include the nonionics such as a C13-C1s fatty alcohol condensed 1l with ~ moles propylene oxide and 4 mole~ ethylene oxide, a C13-C1s fatty alcohol condensed with 5 moles propylene oxide and 10 Il moles ethylene oxide, a C13-C15 fatty alcohol condensed with 6 i moles ethylene oxide and 3 moles propyl.ene oxide, etc.
Generally, the mixed ethylene oxide-propylene oxide , 2~02~2 fatty alcohol condensation products represented by the general formula RO(C3H60)p(C2~40)qH~
_ ~ wherein R is a hydrocarbyl gro~p, such as straight or branched, 1 primary or secondary aliphatic hydrocarbon, preferably alkyl or alkenyl, especially preferably alkyl, of from 8 to 20, preferably 10 to 18, especially preferably 12 to 18 carbon atoms, p i~ a number of from 2 to 8 on average, preferably 3 to 6, and q is a ¦¦ number of from 2 to 12 on average, preferably 4 to 10, can be ~ advantageously used where low foaming characteristics are desired. In addition, these surfactants have the advantage of low gelling temperatures. Mixtures of two or more of the mixed ethylene oxide-propylene oxide fatty alcohol condensation product can be used as can mixtures of the mixed ethylene oxide-propylene oxide condensation products with any of the above alkoxylated nonionics, or mixtures of the ethoxylated nonionics can also be~
used.
Ampholytic detergent~ are also suitable for the invention. Ampholytic detergents are well known in the art and ,I many operable detergents of thi~ clas~ Are disclosed by A. M.
Schwartz, J.W. Perry and J. Berch in "Surface Active Agents and Detergents," Interscience Publishers, New York, 1958, Vol. 2.
Examples of suitable amphoteric detergents include: alkyl I betaiminodipropionates, RN(C2H4COOM)2; alkyl beta-amino-propionates, RN(H)C2H4COOM; and long chain imidazole derivativesaving the general f~rrula:

~' ~Ql~2~2 ,, ~C~2 - R-C ~ N-C~2CH20C~2CM
! OH CH2COOM
; wherein in each of the above formulae, R is a hydrophobic hydrocarbyl group, preferably an aliphatic group, containing from ~i about 8 to 20 carbon atoms, especially 10 to 18 carbon atoms, and I M is a cation, e.g. alkali metal, ammonium salt, amine, alkanol Il amine, etc., to neutralize the charge of the anion. Specific l operable amphoteric detergents include, for example, the di~odium salt of undecylcycloimidiniumethoxyethionic acid-2-ethionic acid, dodecyl beta alani~e, and the inner salt of 2-trimethylamino lauric acid.
I An especially preferred class of amphoteric surfactants are the glycinate derivatives of the formula:
¦ R - (N - [CHRl]x)y - N - W
,¦ T T

~ wherein R is a hydrocarbyl group, prefferably allphatic, of 8 to , 20 carbon atoms, R1 is hydrogen or alkyl of 1 to 6 carbon atoms, I preferably hydrogen, R2 is alkylene of l to 6 carbon atoms, ! preferably methylene, T is hydrogen or W, preferably W, W is '¦ R2COOM, M is hydrogen, alkali metal, alkaline earth metal, I ammonium or substituted ammonium, such as lowre alkanolammonium, 1 e.g., triethanol-ammonium, x is 2 to ~ and y is 2 to 4. A
preferred amphoteric surfactant is of the formula R - (N-CH2CH2CH2)y - N-CH2CM

,i CH2COOM CE12COOM
I wherein R is an aliphatic hydrocarbyl, preferably fatty alkyl or I fatty alkylene, of 16 60 18 carbon atoms, M is alkali metal, and ' 18 2~10202 ! Y is 3 to 4. More preferably R is tallowalkyl (which is a mixture of ~tearyl, palmityl and oleyl in the proportions in Il which they occur in tallow), M is sodium and y is about 3.5, ~ ¦¦ representing a mixture of abou~ equal parts of the amphoteric I surfactant wherein y is 3 and such amphoteric surfactant wherein ¦ y is 4. Among the more preferred amphoteric surfactants of this ¦ type is that available commercially under the trade name ¦ AmpholakTM 7TX, which is obtainable from Kenobel AB, a unit of ¦I Nobel Industries, Sweden.
;I The amount o the detergent active compoundts) will generally range from about 5% to about 75%, more usually from about 5% to about 30%, especially from about 8% to about 15%, by ¦¦ weight of the composition. ~he preferred anionic surfactant is¦
¦¦ usually present in amounts of from about 1 to 25~, preferably ' from about 4 to 20%, especially preferably from about 5 to 15~ by i weight of the composition.
The nonionic surfactant, when present, is usually I contained in amounts of from about 1 to 10~, preferably from about 2 to 8%, by weight and the amphoteric, when present, may I comprise from about 0.3 to 15%, preferably 1 to 10%, especially I preferably from about 2 to 8% by weight, based on the total ,I composition.

ll IV. Detergent Builder 1 Any of the conventional inorganic or organic water-i soluble or water dispersible detergency builders can be used in the composition~ of this invention.
Among the inorganic builders, the alkali metal polyphosphates and alkali metal carbonates or bicarbonates are preferred. Sodium tripolyphosphate is e~pecially preferred but ll ,, 20~021~2 ; other phosphate builder~, such as tetrasodium pyrophosphate, ¦¦ tetrapotassium pyrophosphate, sodlum metaphosphate, and the like, ~¦ can also be used. Mixtures of sodium tripolyphosphate and sodium ~ ¦¦ carbonate, as di~closed in U.S. Patent 4,842,769, incorporated 5 1¦ herein by reference, may al80 be useful.
¦ Suitable builders of the organic type include, for example, polycarboxylate builders, such as aminopolycarboxylates, for example, sodium and potassium ethylene-diamine tetraacetate;
l sodium and potassium nitrotriacetate; and the polyacetal polycarboxylates, such as those de~cribed, for example, in U.S.
Patents 4,144,226 and 4,315,092. Other organic builders of the ¦¦ polycarboxylate type include the water-soluble salt6, especially ¦ sodium and potassium salts, of mellitic acid, citric acid, I pyromellit c acid, benzene polycarboxylic acids, carboxymethyloxy ,, succinic acid, cis-cyclohexane hexacarboxylic acid, and the like.
Citric acid salts, e.g. sodium citrate, is often a preferred builder in non-phosphate or low phosphate formulations, and may also be used in this capacity in the detergent-en~yme l compositions of th:is invention, in addition to any citrate which 1 may be used in the enzyme stabilizing system of this invention.
Polyphosphonate salts represent another useful clas~ of detergency builders, for example, sodium and potassium salts of ethylene diphosphonic acid, ethane-l-hydroxy-l,l-diphosphonic l acid, and ethane-1,1,2-triphosphonic acid.
25 1 Aminopolyphosphonate compounds are also useful builders and may also be advantageously u~ed as seque~trants. Suitable examples include soluble ~alts, e.g. sodium or pota~sium salts, of diethylene triamine pentamethylene phosphonic acid, ethylene diamine tetramethylene pho~phonic acid, and hexamethylenediamine tetramethylene phosphonic acid;

2~ 2~
The present compositions may also incorporate a water soluble acrylic polymer which function as viscosity stabilizers, ¦ and in some cases can act to enhance cleaning performance under - ,¦ actual use conditions and may ~l~o be useful as deflocculents.
I Such polymers include polyacrylic acid, polymethacrylic acid, Il acrylic acid-methacrylic acid copolymer~, hydrolyzed '¦ polyacrylamide, hydrolyzed polymethacrylamide, hydrolyzed acrylamidemethacrylamide copolymers, hydrolyzed 'l polyacrylonitrile, hydrolyzed polymethacrylonitrile, hydrolized 1 acrylonitrilemethacrylonitrile copolyme~s, or mixtures thereof.
Water soluble salts or partial salts of these polymer~ such as ~
the respective a]kali metal (e.g. sodium, pota~ium) or ammonium salts can also be used. The weight average molecular weight of l the polymers is from about 500 to about 15,000 and is preferably within the range of from 750 to 10,000. Preferred polymers include polyacrylic acid, the partial sodium salt of polyacrylic acid or sodium polyacrylate having weight average molecular weights within the range of l,000 to 5,000 or 6,000. The3e I polymers are commercially available, and methods for their I preparation are we:Ll-known in the art.
I For examp:Le, commercially-available polyacrylate I solutions useful in the present cleaning compositions include the sodium polyacrylate solution, Colloid ~ 207 (Colloids, Inc., ¦ Newark, N.J.); the polyacrylic acid solution, Aquatreat ~ AR-602-l A (Alco Chemical Corp., Chattanooga, Tenn); the polyacrylic acidsolutions (50-65% solids) and the sodium polyacrylate powders (M.W. 2,100 and 6,000) and solutions (45~ ~olids) available a~
the Goodrite ~ K-700 ~eries ~rom B. F. Goodrich Co.; and the sodium- or partial sodium salts of polyacrylic acid solutions 2~0202 (M.W. 1000 to 4500) ava~lable as the Acrysol ~ series from Rohm and Haas.
Other natural or synthetic thickening agents or ~ viscosity modifiers may also be added to the application. Such conventional thickening agents include, for example, methyl i cellulose, carboxymethylcellulose (CMC), starch, polyvinyl pyrrolidone (PVP), gelatin, colloidal silica, natural or synthetic clays and the like.
The detergent builder may also include water in~oluble-~ type, especially the aluminosilicate type, particularly thezeolites, such as Zeolite A, usually in the form of its crystalline hvdrate, although amorphous zeolites may also be ,~ useful.
The amount of detergent builder may range from about 5 ; to about 30%, especiaily from about 5~ to about 25%, more j preferably from about 10 to 20~, by weight, based on the total composition.
When the polyacrylate i8 used it is usually pre~ent in only minor amounts~ such as from about 0.05 to 3%, preferably from about 0.1 to :L%, by weight of the composition.
!

V. Other Optional Components Other conventional materials may also be present in the liquid detergent compositions of the invention, for example, ~ soil-suspending agents, hydrotropes, corrosion inhibitors, dyes, perfumes, silicates, optical brightener~, suds boosters, suds depressants, e.g. silicone antifoaming agents, germicides, e.g.
quaternary ammonium ~alts, preservatives, e.g. quaternium 15, anti-tarnishing agents, opacifiers, fabric-softening agents, oxygen-liberating bleaches such as sodium perborate or ~, 20`~2~2 percarbonate with or without bleach precur~ors, buffer~ and the like.
Il A preferred fabric-softening agent is a smectite clay, - ll such as sodium and calcium mon~morillonites, sodium saponites, and sodium hectorites. The sodium and calcium bentonites which I are colloidal clay containing montmorillonite~, such as the '¦ swelling bentonites wherein the predominant cation i5 sodium or¦
calcium, are preferred. The Western or Wyoming bentonites are ¦
I¦ especially preferred. Furthermore, the calcium clays often ' provide superior ~oftening performance than the sodium clays.
!I The swelling capacity of bentonite is generally associated with its fabric softening properties. In water the swelling capacity of sodium bentonite is in the range of 3 to 2b '1 mllliliters/gram, preferably 7 to 15 ml/gram, and its viscosity, , at 5% concentration in water, is usually in the range of 3 to 30 centipoises, preferably 8 to 30 centipoises.
! Preferred swelling bentonite~ are solid under the trademark HI-JEL by Georgia Kaolin Co. These materials are the ~ same as bentonites which were formerly sold under the trademarks MINERAL COLLOID and THIXO-JEL. They are selectively mined and beneficiated bentonites, and those considered to be most useful are available as HI-JEL Nos. 1, 2, 3, etc., corresponding to j THIXO-JEL's Nos. 1, 2, 3, and 4. Such materials have a maximum Il free moisture content (before addition to the liquid medium) of j 4% to 8% and specific gravities of about 26. The bentonite is preferably one which will pass through a 200 mesh U.S. Sieve Series sieve, and most preferably at least 90% of the particles Il will pass through a No. 325 sieve, so that the equivalent ~' diameter of the bentonite may be considered to be les~ than 74 microns, and more preferably less than about 44 microns.

I' 2~o2o2 Typical chemical analyses of some bentonites that are use~ul for making the present liquid detergents show that they contain from 64.8 to 73.0% of SiO2, 14 to 18~ of A1203, 1.6 to !¦ 2.7~ of MgO, 1.3 to 3.1% of CaO, 2.3 to 3.4% of Fe203, 0.8 to 1 2.8% of Na20 and 0.4 to 7.0% of K20.

I Although the Western bentonites are preferred, it is also possible to utilize other bentonites, such as tho~e which may be made by treating Italian or similar bentonite~ containing l relatively small proportions of exchangeable monovalent metals l (sodium and potassium) with alkaline material~, such as sodium carbonate or calcium chloride, to increase the cation exchange I capacities of such products~ It is considered that the Na~O
content of the bentonite should be at lèast about 0.5%, preferably at least 1% and more preferably at least 2~ so that the clay will be satisfactorily swelling, with good softening and I dispersing properties in a~ueous suspension. Preferred ~welling 5 1l bentonites of the types de~cribed above are sold under the trade ¦ names Laviosa and Winkelmann, e.g. Laviosa AGB and Winkelmann G-13.
Other bentonites which are particularly useful in the present liquid detergent compo~ition~ becau~e of their white or l~ very light color include American Colloid Company's Polarite KB
325, a California bentonite, and Georgia Raolin's GK 129, a Mexican bentonite.
When pre~ent, the amount of the clay softening agent I
l will usually be within the range of from about 5 to about 20% by ! weight, preferably from about 6 to 15% by weight, based on the ¦ total composition ; Another optional, but often preferred additive, in minor amounts, is a higher fatty acid, which may be saturated or I

~nsaturated, and may contain from about 10 to about 22 ~arbon atoms, preferably from about 16 to 20 carbon atoms. Oleic acid 1~ is especially preferred in amounts of from about 0.1 to about 5%, - 1¦ preferably from about 0.5 to 2~%, ~y weight of the composition.
5 1l These higher fatty acids function in the invention ¦
¦¦ compositions as anti-foaming agents. They may be used alone for ! this function but are often used in combination with the polysiloxane (silicone) anti-foaming agents. The silicone anti~
l foaming agents will generally be present in minor amounts compared to the fatty acid. Suitable ratios (by weight) of thej i fatty acid anti-foaming agent to silicone anti-foaming agent may I range from about 100:1 to 1:10, preferably 50:1 to 1:1, l especially 30:1 to 2:1.
VI. Liquid Carrier The liquid carrier for the liquid compositions of this invention is preferably water alone but an aqueous carrier containing minor amounts of a lower alcohol, such as ethanol or isopropanol, may also be used in some cases.
Il Generally, water levels may be up to about 70% by weight il of the composition, for example, from about 20 to about 70~, ¦I preferably from about 30% to 60%, by weight. The water may be I deionized, but u~ually tap water i8 BUffiCiellt.
il The viscosity of the present liquid deterqent i9 ¦ normally in the range of about 1000 to 10,000 centipoises, preferably 2000-7000 centipoise~, but products of other suitable viscosities may also be useful. At the viscosities mentioned, the liquid detergent is pourable, stable, nonseparating and uniform. The pH of the liquid detergent suspen~ion usually in I
ll l Il 2 ~ 2 ~ 2 the range of 7 to 11.5, preferably 8 to 10.5, appears to help to maintain product stability and pourability.
I! As necessary, pH modifiers, such as water soluble ba~es, '¦ e.g. caustic, amine~, or ammonra, or acid~, preferably mineral acids, e.q. HCl, will be added to obtain the desired pH level.

VII. Processing Although the ingredients can often be added in any desired order usually the enzyme will be the last added l ingredient and will always follow the addition of the enzyme stabilizing additives.
Conventional manùfacturing methods may be employed ~o a ; large extent in the proseuction of the de~cribed liquid detergent ,¦ compositions. In one procedure, a portion of the aqueous medium Il may be added to a mixing ves~el and the surfactant component~ may be mixed therewith in any suitable order, such as anionic, nonionic and amphoteric detergents, followed by higher fatty acid and hydroxypolycarboxylic acid and neutralizing agent, such as sodium hydroxide ~olution. Then sodium tripolyphoRphate and/or ~ other builders may be added, followed by polyacrylate, enzyme and boric acid and calcium ion source~ Bentonite may be pre-mixed I
il with another portion of the water or may be added directly to the ¦¦ composition, ~ometimes with additional water, after which the balance of the water, brightener, dye and perfume may be admixed.
¦¦ When other components of the detergent composition are al80 ,l employed, they may be added to the mixer at appropriate time~ and ¦ the various orders of addition may be modified to make them appropriate to ~he types of products being made and to the types ¦ of equipment being used.

~l ~

20!10202 In an alternative procedure which has been found convenient, there is first formed a premixture (premix) of the ~
I calcium compound with some or all of the surface active compounds ¦¦ and with some or all of the hy~roxypolycarboxylic acid. The i premix iB prepared as a homogeneous aqueous mixture wherein the aqueous media (e.g. water) may be added as such or a~ a carrier ll for one of the other ingredients in the premix. Anti-foaming I agent may be included in the premix or in the main batch or both.
l Thickening or viscosity modifiers and clay softener are 1 preferably added to the main mixing batch, the viscosity ¦ modifiers generally being added at or near the beginning of the mixing sequence and clay added near the end of the mixing ! sequence before or after the premix.
, A convenient order for addition of the ingredients is 1 water, thickener, coloring agents and/or brighteners, borax and I¦ builder followed by the clay and premix and anti-foaming agent.
I¦ Final pH adjustment is u~ually made right before the enzyme ! component(5) The precise order of addition will depend on the ,, specific ingredients, type of mixing apparatus and desired l characteristics in the final product.
l The following examples illustrate, but do not limit the ! invention. Unless otherwise indicated, all parts and percentages are by welght and temperature~ are in F .

Il ,1.

ll .
~1 2 ~ Q 2 .1 Example 1 A liquid enzyme containing composition is prepared by I¦ first thoroughly mixing the following ingredients in the recited - i! order until each ingredient is~completely dissolved or uniformly ,I dispersed to form a premix.
Amount Added Active Ingred.
Amount Added (a~ 100% a.i) Inqredient (wt% ! (wt$ ) CaCl 0.40 0.4n AEOS~1)(28%) 8.57 2.40 LA~(2) (50%) 18.14 9.07 NaOH (50%) 1.20 0 60 ¦ Carboxymethyl cellulose 0.18 0 18 Tinopal LMS-X (optical brightener) 0.30 0.30 l Citric acid, Hydrate 2.00 2.00 i Borax 3.00 Sodium tripolyphosphate (STPP15.00 15.00 Il LAS (50%) 14.00 7.00 Silicone antifoam ~20~) 3.00 0.60 Calcium Bentonite Clay 11.00 11.00 Jumelle perfume 1.00 1.00 Quaternium 15(~) 0.10 0.10 ,! Tap Water 33 59 33 59 25 :' HCl to adjust p~ to 7.2 Alcalase Enzyme 2.5 L-DX0.6 0.60 I . _ _ ! TOTAL 100 Il .................. . ._ . _ ._ , (1) Sodium alkyl polyethoxy sulfate wherein the alkyl i8 12 to ~ .5 carbon atoms and the polyethoxy ~s 3 ethoxy groups.
(2) Sodium dodecyl benzene sulfonate (3) Dowicil 200 by Dow Chemical [cis-isomer of 1-(3-chloroalkyl)-, 3,5,7-triaza-1-azoniaadamantine chloride]

¦ In the above composition, the enzyme stahilization ¦l 6ystem of borax/citric aoid/calcium chloride is present at a ¦¦ mixing ratio of 3/2/0.4.
l The enzyme stability is measured after being stored for 1 four weeks at each of the following temperatures: 4C, room temperature (20C), 35C and 43C. The re~ults are shown in Table 1. Also shown in Table 1 is the enzyme stability of the ~a I
.

20~2~2 same composition except that the enzyme stabilization system (CaC12, borax and citric acid) is omitted.

T~le 1 ll ENZYME STABILITY AFTER 4 WEEKS AGING
Stabilization Remaining Activity (%) ProductSystem 4C RT 35C 43C
EX 1 Yes 75 37 13 0 Control No 48 7 0 0 Example 2 10 1 The composition shown below is prepared similarly to the ¦ composition of Example 1 Amount Added Nominal Concentration In~redient (wt%~ (as 100% a.i.~(wt%) l Citric Acid, hydrate 2.0 2.0 CaC12 0.3 0 3 ! Borax 3.0 3.0 Nonionic (2) 2.50 2.5 Tallow Amphop4olycarboxy-glycinate ~ ) (30%3 6.00 1.8 AEOS~1) (28%) 31.07 8.7 Sodium Polyacrylate I (MW=2000~l40~) 1.00 0.4 I STPP 15.00 15.0 Calcium Bentonite Clay 11.00 11.0 Oleic Acid 1.50 1.5 Silicone Antifoam (20%) 3~00 0~15 Acid Blue color 0.002 0.002 Food Blue 5 Color 0.001 0.001 Tinopal LMX 0.30 0.3 NaOH (50%) 2.00 1.0 Quaternium 15(3) 0.10 0.1 Jumelle perfume 1.00 1.0 Alcalase 2.5 LDX 0.60 0.6 Water q.~. to 100%
HCl to pH c 7.3 . _ , _ (1) Same as in Example 1 - ~ee footnote (1) (2~ C13-C15 fatty alcohol condensed with 7 moles ethylene 40 ,, oxlde and 4 moles propylene oxide (3) Same as in Example 1 - ~ee footnote (3) 2~402~2 (4) Ampholak T-M- 7TK, from Kenobe A~
i The compo~ition i8 subjected to an accelerated aging I¦ test ("freeze and thaw~) to predict the stability of enzyme - ! activity under long term storage conditions.
¦ The accelerated aging tent is carried out in an ~ automatic computer controlled double boiler. During each test I cycle, the temperature is first decreased at 1C/min. to 28F (-2C) and maintained at this temperature for 2 hours, then the l temperature is increased at 1C/min. to 122F (50C), and j maintained at thi6 elevated temperature for 2 hours. After 8, ,1 24, 40, 72 and 80 cycles, the remaining enzyme activity is !¦ measured. The results are shown in ~able 1. For compari on, the ¦¦ same test is run on compositions identical to that of example 1 il but in which the amounts of borax, CaC12 or citric acid are ,, varied as also shown in Ta~le 1 along with the results of the accelerated aging tests on these comparative composition8. As 4 further comparison, citric acid in the above example is replaced by an equal weight of Sokolan ~ DCS, a mixture of 8uccinic acid l~ glutaric acid and adipic acid (1:1.6:1). The results are also ~hown in Table 2.

20~ 0202 .cO ~ ~

, I N :~ -1 I`t~ ~ O
ll Il _ r ,~1 O
!i >1 0 ~ ~ U~
Il v ~r U r~ ~a U U
I! ~ u j~ ~ C ~r ~1 Ut O ~ ~r O r-l ~
N N U ~ _I N N

N E
l E~ O 1~ ~ U
tLl ~4 ~ ~ C~ O ~ ~ ~r ~ .~
t~ N ~1 ~ ~ N ~ N V
- :~
I~U ~
l I JJ :>~ 1-- N L(l L~l ~D ~r U
Il m ~ Cl~ u u~ ~ ~ ~ 0 .. C
,1 ~ G) ~ C UUil ~ ~` o ~ U~
~ a~ 0000 0 o V U ~

,_1 C lt X
J:~ V r~ I I N N N 0 ~ x 3 m C O E
~4 . _ _ U~
a~ ~
a) ~ a~ ~ 0 i Q.~ 0 a~ x O ~0 6 X ~ ~ ,~ ~
1~ 0 E~ ~ x ~e x x ~: O
x ~ o X--X ~ ~ W ~1 o u~
i ~ W
l _ . _ -ll In O In ll l il ~ 31 I The composition of Example 2 and the Sokolan R DCS
I control are also compared for long term storage (aging) characteristics by meaguring the remaining enzyme activity (a~ a ~ I percent of the original activi~y) at 4C, room temperature, 35C
and 43C. The enzyme stability in term~ of remaining activity (percent of original activity) is measured at the end of 2 weeks, 4 weeks and 8 weeks at each temperature. The results are shown in Table 3.
I T~BLE 3 10 Enzyme Stability Long Term Aging . ~ .. ~
__ Aainq Temperature ~
Time 4C~ T. 35C _ 43C
~Weeks) ~EX2) EX2 Control EX2 Control EX2 _Control _ Example 3 20 1 Component Per ent Pentasodium tripolypho~phate 11.0 Bentonite (Georgia--Kaolin 129) 12.0 Sodium carbonate 2.0 Sodium sesquicarbonata 2.0 Sod1ut~)linear tridecylbenzene sulfonate (LTBS) 3 00 Carboxymethyl cellulose (CMC) 0.2 Optical brightener tTinopal LMX-X) O.3 Perfume 4 Enzyme (Espera~e 8~0L)(2) 1 0 CaCl2 0.6 Borax 2.5 Cltric Acid 2.0 ~ater and adjuvants Balance . ...~
(1) Sodium alkyl polyethoxy sulfate wherein alkyl iB 12 to 15 carbon atoms and the polyethoxy is 3 ethoxy groups.
(2) "Esperase" sold by Novo Industries having an activity of ! 8.0 KNPU/gram.
I

1~ 2~02~2 The composition shown above is prepared by the following procedure: 30.0 parts of deionized water at 40F. are ! added to a suitable mixing apparatus such as a vertical _ cylindrical tank equipped with~a ~tirrer. With the stirrer adjusted for medium agitation, a mixture consi~ting of 2.0 parts anhydrous soda ash, 2.0 parts sodium sesquicarbonate, and 0.2 parts sodium carboxymethyl cellulose is incorporated into the water. The stirrer speed is then increased to maximum agitation and a mixture comprised of 11.0 parts pentasodium tripolyphosphate and 12.0 parts bentonite i8 810wly added to the mixing apparatus over a period of 10-15 minutes to form an off-white suspension. The agitation speed is then decreased to a slow/medium setting while 8.64 parts of high AI (about 55%) LTBS
slurry is added. Thereafter the optical brightener/color solution is added consisting of O.3 parts Tinopal LMS-X (CIBA-GEIGY), 0.909 parts colorant, and 4.02 parts deionized water.
Once a uniform blueish-green colored solution i8 obtained, 0.4 parts of perfume i3 added to the mixture under agitation. This i8 followed by the slow addition of 0.6 parts CaC12 and 2.5 parts borax as a two component ~lurry. Stirring is continued until the mixture is uni:Eorm in appearance and then 2.0 parts of citric acid and 9.0 parts water are slowly added. Agitation of the mixture is then reduced while 10.95 parts of a mixed AI
detergent base consisting of an LT~S slurry (about 30% AI) and AEOS (About 27.5% AI) is added to the mixture. This is followed by the slow addition of 1.0 parts proteolytic enzyme with contlnuous agitation until all materials are completely dispersed or dissolved~
Enzyme stabilization similar to that of Example 1 will be obtained.

Claims (22)

1. Claim 1. An enzyme-containing liquid detergent composition comprising (A) from about 5 to about 75%, by weight, of one or more surface active detergent compounds;
   (B) from about 5 to about 30%, by weight, of one or more water-soluble detergency builders;
   (C) from about 0.01 to about 5%, by weight, of at least one enzyme selected from the group consisting of proteases, amylases and mixtures thereof;
   (D) an enzyme stabilization system comprising (i) from about 0.25 to about 10%, by weight, of a boron compound selected from the group consisting of boric acid, boric oxide, and alkali metal borates;
   (ii) from about 1 to about 3%, by weight, of an hydroxypolycarboxylic acid selected from the group consisting of aliphatic di- and tri-carboxylic acids with from 1 to 4 hydroxyl groups and with from 4 to 8 carbon atoms; and (iii) a water soluble calcium salt in an amount sufficient to provide from about 18 to about 50 millimoles of calcium ion per liter of the composition; and (E) water.
2. Claim 2. The liquid detergent composition of claim 1 wherein the detergency builder comprises an alkali metal polyphosphate.
3. Claim 3. The liquid detergent composition of claim 2 wherein the alkali metal polyphosphate is sodium tripolyphosphate.
4. Claim 4. The liquid detergent composition of claim 1 wherein the enzyme comprises a protease.
5. Claim 5. The liquid detergent composition of claim 1 wherein the enzyme stabilization system comprises (i) borax, (ii) citric acid and (iii) calcium chloride.
6. Claim 6. The liquid detergent composition of claim 5 wherein the enzyme stabilization system comprises from about 0.5 to about 8% by weight (i), from about 1.5 to about 2.5% by weight (ii) and (iii) in an amount sufficient to provide from about 22 to about 36 millimoles of calcium ion per liter of the composition.
7. Claim 7. The liquid detergent composition of claim 1 wherein the enzyme stabilization system comprises from about 0.5 to about 8% by weight (i), from about 1.5 to about 2.5% by weight (ii) and (iii) in an amount sufficient to provide from about 22 to about 36 millimoles of calcium ion per liter of the composition.
8. Claim 8. The liquid detergent composition of claim l which further comprises a softening effective amount of a clay softening agent.
9. Claim 9. The liquid detergent composition of claim 1 which comprises (A) from about 5 to about 30%, by weight, of a mixture of (a) non-soap anionic surface active compound and (b) nonionic surface active detergent compound at an (a):(b) ratio, by weight, of from about 1:4 to about 10:l.
10. Claim 10. The liquid detergent composition of claim 9 wherein the anionic (a) is an alkyl polyethoxy sulfate wherein the alkyl is from 10 to 18 carbon atoms and which includes from 3 to 11 ethoxy groups, and wherein the nonionic (b) is a mixed ethylene oxide-propylene oxide fatty alcohol condensation product of the formula RO(C3H6O)p(C2H4O)qH
    
    wherein R is a straight on branched, primary or secondary aliphatic hydrocarbon, of from 6 to 20 carbon atoms, p is a number of from 2 to 8 on average, and q is a number of from 2 to 12 on average.
11. Claim 11. The liquid detergent composition of claim 1 which further comprises one or more additional adjuvants selected from higher fatty acid of from about 10 to 22 carbon atoms, soil-suspending agents, hydrotropes, corrosion inhibitors, dyes, perfumes, silicates, optical brighteners, perfume, antifoaming agents, germicides, fabric softening agents, pH
    modifiers and pH buffers.
12. Claim 12. A built aqueous liquid enzyme containing cleaning composition comprising (A) from about 5 to about 30%, by weight, of at least one surface active detergent compound selected from the group consisting of anionic, nonionic and ampholytic detergent compounds, (B) from about 5 to about 25%, by weight, of at least one detergency builder salt selected from the group consisting of alkali metal polyphosphates, alkali metal carbonates, alkali metal nitrilotriacetates, polyacetal carboxylates, and mixtures thereof;
    (C) from about 0.1 to about 3%, by weight, of a protease, amylase, or mixed protease-amylase enzyme;
    (D) an enzyme stabilization system containing (i) from about 0.5 to about 8%, by weight, of boric acid, boric oxide or alkali metal borate;
    (ii) from about 1.5 to about 2.5%, by weight, of citric acid; and (iii) a water-soluble calcium salt in an amount sufficient to provide from about 22 to about 36 millimoles of calcium ion per liter of the composition;
    (E) from about 5 to about 20% by weight of a clay softening agent; and (F) water, and optionally perfume and other adjuvants.
13. Claim 13. A method of laundering stained or soiled fabrics comprising contacting the fabrics with the stabilized enzyme containing liquid detergent composition of claim 1.
14. Claim 14. A stabilized enzyme preparation useful as a laundry additive which consists essentially of at least one enzyme selected from the group consisting of proteases, amylases and mixtures thereof, and an enzyme stabilizing effective amount of an enzyme stabilization system consisting essentially of (i) from about 0.25 to about 10 parts by weight of a boron compound selected from the group consisting of boric acid, boron oxide, and alkali metal borates; (ii) from about 1 to about 3 parts by weight of an hydroxypolycarboxylic acid selected from the group consisting of aliphatic di- and tri-carboxylic acids with from 1 to 4 hydroxyl groups and with from 4 to 8 carbon atoms; and (iii) a water soluble calcium salt in an amount to provide from about 18 to about 50 millimoles of calcium ion per liter.
15. Claim 15. The stabilized enzyme preparation of claim 14 in the form of a powder.
16. Claim 16. The stabilized enzyme preparation of claim 14 in the form of an aqueous solution.
17. Claim 17. The stabilized enzyme preparation of claim 14 wherein the hydroxypolycarboxylic acid is citric acid.
18. Claim 18. The stabilized enzyme preparation of claim 17 wherein the enzyme stabilization system contains from about 0.5 to about 8 parts of (i), from about 1.5 to about 2.5 parts (ii) and (iii) in an amount sufficient to provide from about 22 to about 36 millimoles of calcium ion per liter.
19. Claim 19. The stabilized enzyme preparation of claim 18 wherein (i) is borax and (iii) is calcium chloride.
20. Claim 20. A composition for addition to a protease or amylase enzyme containing aqueous laundry detergent composition to stabilize the enzyme against degradation, said composition consisting essentially of (i) from about 0.25 to about 10 parts by weight of boric acid, boron oxide or alkali metal borate; (ii) from about 1 to about 3 parts by weight of citric acid, and a water soluble calcium salt in an amount to provide from about 18 to about 50 millimoles or calcium ion per liter when added to an aqueous laundry detergent composition containing up to about 5% by weight of said enzyme.
21. Claim 21. The composition of claim 20 in the form of a powder.
22. Claim 22. The composition of claim 20 in the form of an aqueous solution.