CA1317187C - Thixotropic aqueous liquid automatic dishwashing detergent composition - Google Patents

Abstract

PATENT

THIXOTROPIC AQUEOUS LIQUID AUTOMATIC
DISHWASHING DETERGENT COMPOSITION

ABSTRACT OF THE DISCLOSURE

Thixotropic aqueous liquid automatic dishwashing detergent composition with improved anti-filming and anti-spotting properties and method of using the detergent composition. The detergent composition comprises silica anti-filming agent, polyacrylate polymer builder, inorganic builder salts, chlorine bleach, bleach-stable detergent and a thixotropic thickener. The compositions provide reduced filming and spotting on dishware, glassware, china and the like, particularly in hard water, and remain stable against phase separation.

Description

13171~7 PATENT

THIXOTROPIC AQUEOUS LIQUID AUTOMATIC
DISHWASEIING DETERGENT CQMPOSITION

FIELD OF TH~ INVENTION
The present invention relate~ to a thixotropic aqueous liquid automatic dishwashlng detergent composition with improved anti-filming and anti-spotting propertie3 and method of using the detergent composition to clean dishware, glas~ware, china and the like. The dishwashing composition contains silica, as the anti-filming a~nt, polyacrylic acid polymer builder inorganic bu~lder salts, chlorine bleach, bleach stable detergent ~nd a thixotropic thickener.
The detergent dishwAshing compoæition of the present invention reduces filming and ~potting on dishware, glassware, china and the like, particularly in hard water, and rem~ stable against phase sep~ration.
More specifical~y, the invention relate~ to the use o~ silica a~ an anti filming ager~t and poly~crylic acid polymer builder in thixotropic aqueous liquid dishwashing detergent composition~ to reduce filming and spotti~lg.
The detergent compo~ition~ do no require an added rinse aid, are stable in storage, do not settle and are readily redispersible and are pourable.
The present invention al~o rel~tes to thixotropic aqueous suspension with improved physical stability. The invention relates to the u8e of long chain ~atty acids, metal s~lts of fatty acid~ and clay a~ thixotropic agents for forming stable gel-like liquld suspension~ ~uitable for use a~ liquid automatic dishwasher detergent composition.
The present invention specifically relates to aqueous liquid automatic dishwashing detergent compositions having thixotropic propertie~, improved anti-filming snd anti-spotting propertie~ and improved physical stability 13171~7 properties, which are readily dispersible in the washing medium to provide effectiv~ cleaning of dishwar~, glassware, china and the like.
PRIOR ART
Commercially available household-machine dishwasher detergents provided in powder form have several dlsadvantage~, e. g. non-uniform composition; costly operations necessary in their manufacture; tendency to cake in storage at high humidities, resulting in the formation of lump~
¦ which are difficult to disperse; dustiness, a source of particular irritation l to user~ who su~fer allergies; and tendency to c~ke In the dishwasher10 ¦ machine dispenser Liquid forms of such compo~itions, however, generally cannot be used in automatic dishwashers due to high foam levels, unacceptably low viscositie~ and exceedingly high alkalinity.
In addition, the presently used Iormulated powder deter~ents frequently require a separate step of hand towel wiping and drying of the dishware, glassware, china and the like to avoid leaving undesirable trace~
or f31m of precipitated calcium snd magne~ium salts. The u~e of liquid detergent compositions present othsr problem~. The builder salts settle in storage and are not readily redispersed. The compositions al~o frequentl7 becoma thicker in storage and are not rea~ly pourable.

2 0 P~ecent research and development acti~rity has focused on the gel or "thixotropic" form o~ such compositions, however, such compositions have generally proven to be insufficiently viscous to remain "anchored" in the dispen~er cup of the dishwasher, and moreover yield spotty re~idues on dishware, glassware, china and the like. Ideally, thixotropic cleansillg compositions should be highly viscous in a quiescent state, Bingham plastic in nature, and have relatively high yield values. When subjected to shear stresses, however, such as being shaken in a container or squeezed through an orifice, they should quickly fluidize and, upon cessation of the applied shear stress, quickly revert to the htgh viscosity/ Bingham plastic ~ 13171~7 state Stability is likewise of primary importance i e. there ~hould be no significant evidence of phase separation or leaking after long standing.
For effective use it is generally recomrnended that the automatic l dishwashing detergent, hereinafter also designated ADD, contain (1~ sodium 5 ¦ tripolyphosphate (NaTPP) to soften or tie up hard-water minerals and to emulsify and/or peptize soil; (2) sodium silicate to supply the alkalinity necessary for effective detergency and to provide protection for fine china gla~e and patterrl; (3) sodium carbonate, generally con~idered to be l optional, to enhance alkalinity; (4) a chlorine-releasing agent to aid in the 10 ¦ elimination of soil speclcs which lead to water spotting; and (5~
¦ defoamer/surfactant to reduce foam, thereby enhancing machine ef~iciency ¦ and supply~ng requisite detergency. See, for example, SDA Detergent~ in ¦ Depth, "Formulations Aspect8 of machine Dishwa~hing," Thomas Oberle ¦ (1974). Cleansers approximating to the afore-dsscrlbed compositioll~ are ¦ mostly liquids or powder~. Generally, such compositlons omit hypochlorite ¦ blesch, ~ince it tends to react with other chemically active ingredients, ¦ particularly surfactant, thereby degrading the suspending or thixotropic ¦ agent and impairing it~ effectiveness.
¦ Thu~, U . S . Patent No. 3, 985, 668 describes abrasive ~couring cleaner~
¦ of gel-like consistency containing ~1) suspending agent, preferably the ¦ Snlectite and attapulgite types of clay; (2) abrasive, e.g. silica sand or ¦ perlite; and (33 filler comprising light den~ity powdered polymers, ¦ expanded perlite and the like, which has a bouyancy and thus stabilizing effect on $he composition in addition to ^~erving as a bulking agent, thereby replacing water otherwise available for undesired supernatant layer formation due to leaking and phase destabilization. The foregoing are the essential ingredients . Optional ingredients include hypochlorite bleach ~
bleach stable surfactant and buffer, e. g. silicate3, carbonates, and monophosphates. Builders, such as NaTPP, can be included as further optional ingredients to ~upply or ~upplement building function not provided 13171~7 by the buffer, the amount ~f such builder not exceeding 5% of the total composition, according to the patent . Maintenance of the desired ( greater than) pH 10 level~ is achieved by the buffer/builder components. High pH
i~ sai~ to minimize decomposition of chlorine bleach and undesired interaction between surfactant and bleach. When present, NaTPP is limited to 5%, a~ stated. Foam killer is not disclosed.
In U . K . Patent Application GB 2 ,116 ,199A and GB 2 ,140, 450A, both of /
which are assi~ned to Colgate-Pa~mol~re, liquid ADD compositions are disclo~ed which have properties desirably ch~racterizing thixotropic, gel-type ~tructure . and which include esch of the various ingredients necessary for effective detergency with an automatic di~hwasher. The normally gel-like aqueous automatic dishwaQher detergent composition having thixotropic properties includes the following ingredients, on a weight ba6is:
~a) 5 to 35% alkali metal tripolyphosphate;
~b) 2.5 to 20~ ~odium silicnte;
(c) O to 9% slkali metal carbonate;
(d) 0.1 to 5% chlorine bleach stable, water dispersible organic detergent active material;
~e~ O to 5~6 chlorine bleach stable foam depressant;
~f) chlorine bleach compound in an amount to provide about 0.2 to 4% of availuble chlo~ine; . .
( g) thixotropic thickener in an amount sufficient to provide the composiiion with thixotropy index o~ about 2.5 to 10; and ~h) sodium hydroxide, as necessary, to adjust pH.
ADD composition~ 80 formulated are low-foaming; are readily soluble ln .
the washing medium and most effective at pH values beqt conducive to improved cleaning performance, viz, pH 10 . 5-13 . 5 . The compositions are normally of gel consistlency, i.e. a highly viscous, opaque jelly~like material having Bingham plast lc character and thus relatively high yield values .
Accordingly, a definite shear force is necessary to initiate or increase flow, i ~tP~D6~rRii 4 13171~7 ~uch an would obtnln wttl ln tha sgltnted dl~penser cup o~ nn oncrFlzed outomatlc dlshwaHher. Under such condltlon~ the compo61tion la quickly fluldlzed snd eu~lly dlspersed When the shear force i~ dlocontinued tl e tluld composltlon qulckly reverts to R hlgh ~rl3co~1ty Ulnghnrn plostlc stote closely npproxlmiltlng Its prlor conslstency.
U . S . Patent 4 511 487 d~ted Aprll 16 19~5 descrlbes c low-foaming detergent paste ~or dlshwsshers. The composltlon 18 based on a mlxture of flnely dlvlded hydroted sodlum metaalllcnte nn nctlv~ chlorlne compound and n thickenlng agent which i~ ~ rollated sllicste of the hectorlte typa.
Smnll omount of nonionlc ten~ides and slkall metal c~rbonates Qnd/or hydroxlde~ msy be u~ed~
A related Canadian opplicatlon which 1~ a~lgned lo the common R9Hlgnea 18 Serlsl No. 526,708, filed January 6th, 1987.
The copending application dlHc10ses thlxotroplc aqueous automatlc dlshwsshlng detergent compos1lion which contnlna ~ lon~ chsin fatty acid a~ a thixotroplc thlckener agent.
Ano~hE~r relnted Canadian appllcatlon whlch 19 0190 ~slgned to lha common sHsignae Is Serllll No. 550,065 nled October 23rd, 1987.
This copendir.g application discloses an aqueous llquld thlxotroplc clay dl~hw~l~hlng detergent composltlon comprising o metsl sait oi a long chnin fntty aclcl ~nd 1 polyncrylie ~cld polymer or ~lt stabiiizing seent.
ADVANTAGES OVER TTIE PnlOR AIIT
The thlxotroplc nqueous liquld detergant composltlonn of the present Inventlon overcome mony of tha prior art problem~ assocloted w~th powder and llquld detergent~. Becau~e of the acld~tlon oE a smsll effectlve omourlt of n slllca ontl-fllmlng sgent nnd polyacryllc ncld polymer or sDlt bullder to the compo~ltlon on ndded rlnse ald 19 not requlrecl Elnd towel wlplng oncl dry1ng ~re not requlred to obt~ln dry ~porkllng clenn dlHhes glllsses cup~
and entlng utan~ . Ths thixotroplc ~queous llquld tietergent eomposltlon ~ . `;

1 3 ~ 7 1 & 1 62301-1520 has the addi~.ional advantages of being stable, non-settling in storage and readily redispersible. The liquid compositions o~
the present invention are easily pourable! easily measured and easily put into the dishwashing machines.
An additional and unexpected advantage of adding the silica anti-filming agent to thP detergent formulation is that the silica inhibits brown stain formation in the dishwashing machine. The brown stain is formed by the deposition in the dishwashing ma~hine of iron and/or manganese oxides. The brown stain ~ormation is a particularly serious problem in areas having hard water. The silica in the ~ormulation acts on the iron and/or manganese in the wash water to prevent their deposition in the dishwashing machine as iron and/ox manganese oxides.
The present invention seeks to provide a thixotropic aqueous liquid automatic dishwasher detergent composition that has improved anti-filming and anti-spotting properties.
The invention also seeks to provide a thixotropic aqueous liquid detergent eomposition which is stable in storage, easily pourable and readily dispersible in the dishwashing water.
The invention further seeks to provide a method oi washing dishware, glassware, china and the like in an automatic dishwashing machine using a thixotropic aqueous liquid detergent composition in which a separate rinse aid is not added or needed.
The invention also seeks to provide a method of washing dishware, glassware, china and the like in an automatic washing machine using an aqueous liquid detergent composition by whieh method the dishware, glassware, ehina and the like are machine dried without leaving traces or a ~ilm.

,~, 1 31 7 1 ~7 62301-1520 This invention further seeks to provide ~table aqueous thixotroplc aqueous liquid compositions, especially automatic dishwasher datergent compositlons, by incorporating in the aqueous suspenslon a small effective amount of a silica anti-filming agent and polyacrylic acid polymer or salt builder. There is also added a minor amount of a fatty acid, metal salt of a fatty acid and~or clay thixotropic thickener effective to inhibit the settling of the suspended particles and to prevent phase separation.
DETAILED DESCRIPTION OF THE INVE~TION
The invention will become more readily understood from the following detailed description of the invention and preferred embodiments thereof which are achieved by incorporating in an aqueous liquid detergent composition a small but affective amount of a silica anti-filming agent and polyacrylic acid polymer or salt builder. The physical stability of the composition is improved by the addition of a fatty acid, metal salt of a fatty acid and/or clay thixotropic thickener. More particularly, there is provided a normally gel-like automatic dishwasher deter~ent composition comprising water, at least one ingredient selected from the group consisting of or~anic detergent, detergent builder, sequestering agent, foam inhibitor and mixtures thereof in which is incorporated from about 0.5 to 5% of a silica anti-filming agent and about 2 to 14% of a water soluble polyacrylic acid polymer or salt builder and a sufficient amount of a thixotropic thickener to provide a thixotropic index of about 2.5 to 10. The silica anti-filming agent has a particle size of about 0.1 to 10 microns. The water polyacrylic acid or salt has a molecular weight of about 500 or preferably 1,000 to 100,000. In a preferred embodimen~ of the invention there is .....

13171~7 62301-1~20 added ~o the composition a sufficient amount of a long chain fat~y acid or me~al ~alt of a long chain fatty acicl, or either of the foregoing in admixture with a clay thixotropic thickener to provide a thixotropic index of about 2.5 to 10 and to inhibit settling of the suspended particles, such as alkali metal builder salts, etc.
In accordance with this aspect, the present invention provides a normally gel-like aqueous liquid automatic dishwasher detergent composition having thixotropic properties whi~h includes, on a weight basis:
(a) 5 to 35~ dekergent builder, e.g. alkali metal tripolyphosphate;
(b) 2.5 to ~0% sodium silicate;

7a 13171~7 (c) 0.5 to 5% silica anti-filming agent;
(d) 2 to 14% polyacrylic acid polymer or salt builder;
(e) 0 to 9 % alkali metal carbonate;
(f) 0.1 ~o 5% chlorine bleach stable, water dispersible organic detergent active material;
( g) 0 to 5% chlorine bleach stable foam depre~sant;
(h) chlorine bleach compound in an amount to provi~le about 0.2 to 4% of available chlorine;
(1) thixotropic thickener in an amount suficient to provlde a thixotropic index o~ about 2.5 to 10.
(j) O to 8% sodium hydroxide; and (k) balancs water.
Also related to this specific aspect, th~e invenffon provides a me~hod for cleaning dishware in an automatic dishwa~hing machine with an aqueous wash bath containing an effective ~mount of the liquid automatic dl~hwasher det~rgent ~LADD) composition as described above. According to thi3 aspect of the inventlon, the LADD composition carl be readily poured irlto the dispen~ing cup of the automatic dishwashing machine and will, within just a few ~econda, promptly thicken to its normal gel-like or pasty state to remain sacurely within the dispensing cup until shear ~orces are again applied thereto, such as by the water spray Prom the dishwashing machine.
The invention will now be de~cribed in greater detail by way of specific embodiments thereof.
The LADD products of for example the prior disclosure in the aforementioned GB 2,116,199A and GB 2,140,450A exhibit rheological properties a~ evaluated by testing product viscosity as a Punction of shear rate. The compositions exhibited higher viscosity at a low shear rate and lower vi~cosity at a high shear rate, the data indicating efficient fluidization and gellation well within the shear rates extant within the 30 standard dishwasher machine. In practical terms, this means improved 13171~7 pouring and processing characteristics a~ well as leqs leaking in the machine dispenser-cup, compared to prior liquid or gel ADD produets. For applied shear rates corresponding to 3 to 30 rpm, viseo~ities (BrookPieId~
correspondingly ranged from about 10,000 to 30,000 Cp9 to about 3,0lD0 to 7,000 cps, a~ measured at room tempersture by means of an LVT Brookfield viscometer after 3 minute~q using a NoO 4 spindle. A shear rate of 7 . 4 sec l corresponds to a ~pindle rpm of about 3. An approximate 10-fold increa~e in 6hear rate produces about a 3- to 9-fold reduction in vi~cosity. .
The compositions o~ the assignee's prior invention thus exhibit threshold fluiclization~ ~t low~r shear rates and of significantly greater extent in terms o~ incremental increases in shear rate versus incremental decr0ase in viscosi~y. This property s)~ the I.ADD product~ o the pris)r invention i~
summarlzed in terms of a thixotropic Index (TI) which i8 the ratlo of the apparent visco~ty st 3 rpm and at 30 rpm. The prior compo~ition~ have a TI of from 2 to 10. The LADD compositiolls should exhlblt sub~tantial and quick return to prlor quiescent state con~istency when the ~hear force is discontlnued .
In terms of apparent viscosity, it has been ascertained that so long as the viscosity at room tempernture (22~1C) meu~ured in a Brookfield Viscosimeter HATD, using a number 4 spindle at 20 rpm, is less than about 20, 000 cps, the compositlon can be readily shaken so that a thixotropic composiffon can be easily "nuidized" or "liquefied'l to allow the product to be dispensed through a conventional Yquee~e tube bottle or other convenient dispenser.
The present invention is based upon the surprising discovery that substantially improved anti-filming and anti-spotting properties can be obtained by adding to the thixotropic aqueous liquid detergent composition a ~mall effective amount of a silica anti-filming agent and polyacrylic acid polymer or salt bu~lder . The physieal stability , i. e ., resistance to phase 1 3 1 7 1 ~ 7 62301-1520 saparation, settling, etc. can be achieved by adding to the composition a small effective amount of a thixotropic ~hickener and stabilizing agent.
ANTI-FILMING AGENTS
The silica anti-filming agent materials that can be used are fumed or precipita~ed synthetic or natural silica.
The silica may be amorphous or crystalline.
The silica material that is used may contain up to about 0.1 to 5% alumina (Al203), usually up to about 0.5 to 3%
and more usually about 1% alumina, based on the weight of silica.
A preferred silica material is Syloid~ 244 which is amorphous silica and is provided by ~.R. Grace & Co.
Another preferred silica material is Huber*Zeo*49 which is amorphous silica and is provided by J. M. Huber Corporation and contains about 1% alumina (A1203). The presence of as little as 1% A1203 is found to help reduce the hydrolysis and subsequent solubility of the silica in the highly alkaline automatic dishwashing detergent composition.
The particle size of the silica material that is used is important in achieving the desired anti-filming properties. ~
The silica particles that are used are finely divided and can have a particle size of about 0.10 to 10 microns, preferably 0.50 to 8 microns and more preferably about 1.0 to 5.0 microns. The silica particles of this size and in the amount used herein are not abrasive.
The finely divided silica material particles in the dishwashing wash act to coagulate proteinaceous particulate *Trade-mark ~0 1 3 1 7 1 ~7 62301-1520 soils and keeps them in suspension ancl with the polyacrylic acid polymer or salt acts as an anti-redeposition agent to preven~ them from depositing on the clean glass and dishware.
The amount of silica antl-filming agent that can be used to achieve the desired improvement in filming and spotting will depend on the hardness of the water, detergent active compound, inorganic salts and other ADD ingredients. The silica anti-filming agent is particulary effective in hard wash water of, for example, 300 ppm hardness or more.
The amount of silica an-ti-film agent that is used can be about 0.5 to 5%, preferably about 1 to 4~ and more preferably about 1.5 to 3~ by weight based on the weight of the entire composition.
POLYACRYLIC ACID POLYMERS AND SALTS THEREOF
The polyacrylic acid polymers and salts thereof that can be used are generally commercially available and are briefly described as follows.
The polyacrylic acicl polymers and salts thereof that can be used comprise water soluble low molecular weight polymers having the formula _ _ _ - f R3 COOM n wherein the R1, R2 and R3 can be the same or different and can be hydrogen, C1-C4 lower alkyl, or combinations thereof.
The value of n is 5 to 1000, preferably 10 to 500, and more preferably 20 to 100. M represents hydrogen, or an alkali metal such as sodium or potassium. The preferred substituent for M is sodium.

, ~, ~ J

~ 3 1 7 I ~7 62301-1520 The preferred R1, R2 and R3 groups are hydroyen, methyl, ethyl and propyl. Preferred acrylic acid monomer is one where R1 to R3 are hydrogen, e.g. acrylic acid, or where R
and R3 are hydrogen and R2 is methyl, e.g. methyl acrylic acid monomer.
The degree o$ polymerization, i.e. the value of n, is generally deteLmined by the limit compatible with the solubility of the polymer in water. The terminal or end groups of the polymer are not critical and can be H, OH, CH3 or a low molecular weight hydrocarbon.
The polyacrylic acid polymers and salts thereof can have a molecular weight of 500 or 1,000 to 100,000, preferably 1,500 to 50,000 and especially preferably 2,000 to 10,000.

lla ~ q Speclflc polyncrylle neld polymer~ which cun be u~ed Inclu(le IlIe Acry~ol*LM~Y acrylic acid polymere from Rohm un(l l-lnn9, such na lh Acrysol LMW-45NX, H neutrn~i~ed sodlum snlt, whlch hns a moleculnr welght of nbout 4,500 and Acry601 LMW-20NX, a neutraltzed sodium snlt, whlch has n molecular weJght o~ nbout 2, 000 . The low moleculnr welght ncryllc ucld polymer~ enn, for exnmple, have n moleculnr welght of nbout 1,000 to 10,000. Another polyacryllc acid polymer that can be used 18 Alcosperse *
110 (from Alco) whlch la a sodlum salt of an organic polycarboxylate nnd whlch has n moleculnr welght of nbout 100,000, The sbove polyncryllc ncld polymer3 and salts thereof can beJ mnde uslng procedure~ known In the nrt, see for exnmple U.S. Patent 4,203,858.
The nmount of polyserylle acld polymer or sult bullder thflt cnn be used to uchleve the deslred Improvement In anti-fllming ~nd antl-spottlng propertles wlll depend on th~ hnrdness of the wnter, detergent actlve compound, Inorganle salts nnd other ADD Ingredlents, The polyncrylle acid or aalt bullder la partlcul~rly erfcctlve in reduelng spotting In hard w~tflr of, for exnmple, 30~ ppm hardneas or more .
Generally, the amounts of the polynerylle ncld polymer or salt that can be used nre tn the rnnge o~ ~rom about 2.0 to 19~, preferllbly frorn about 3 . O to 12d; especlnlly preferably nbout 4 to 10%.
TIIIXOTROPIC TIIICNENERS
The thlxotrople thlekener~ or suspendlng ngents thnt can be used In aceordnnca wlth the present Inventlon to provide the nqueous medlum wlth lhlxotrople propertle~ muy be orgnnle, for exnmple, fntty neld or fatty uclcl polyvnlent metnl s~lts or Inorgnnlc eollokl formlng clny rnnterlnls. I`lle ~hlxotrople thlckenera should be stable to high alkullnlty and atable to chlorlne bleach compounds such ns sodlum hypoehlorlte. The preferred thlxotrople thlckencrs comprlae ths fntty nclds, the fn~ty nc~d polyvnlent metnl salts nnd the Inorgunle, eollold-~ormlng clnys of smectite nnd/or *Trade-mark 1 3 1 7 1 ~, 7 62301-1520 pulE~i~e type~. Th~ ~mount of tho thlxotroplo lhlckancr u3~d ~lll depend on the psrtlcular thlckener uand, but surflclent thlclcenar 13 ~dded to lhn forrnululloll to provlde the composltlon wllh ~ thlxotropy In~lex of about 2.5 to lO, Thc preferred f~tty acid thlxotroplc thlck~nel ~ sr~ tha hlgher ullpllatlc futly monocurboxyllc acicla hnvln~ from ~bout ~ to ~boul 22 curban ~toms, moru praferubly from nboul 1n O~ to 20 carhm aterns, Fmd especially pref`erQbly from ubout 12 to 18 carbon atom~, Inclu~lva of the cnrbon utom of tha cnrboxyl group of lha fntty ~cld. Thc allptlatlc rDclJc~ll mny be ~atural~d or unsnturuted and may be ~tralght or branched. Slr~l~h~ chnin ~aturnt~d rntty acldH are preferred. Mlxturcu of ~ntty ncldY may be u~d, uuch 1l~
tho~e derlved from nuturnl ~ourc~e, ~uch a~ tallow futly ~cld, coco futty ncld, ~oya futty ncld, ctc,, or from ~ynthetlc sourcH~ ~vallable from industr~DI manufactuFlng proc~a~.
Thu~, axampla~ of thH futty ~cldY whlch c~n bn us9d a~ lhlck~ner~

Include, for e~c~mplc, decunolc ucld, lauria ucld, dodecanoic acld, palmlli&
acld, myri~tla ~cld, atsllric t~cld, olelc acld, elco~ùnol& acld, tallow fulty ncki, c~co fatty ~cld, ~oyu f~tty acld and mlxture~ of thn~s ~clde. Ste~lrlc ucld and mlx~d futty ~cld~, n. g. coco fatty flcld, ~re prafMrred.

Thu amount o- thn f~tty ucld thickennr to ucl~ the de~lrad vulues of lhlxotropy cnd pllyslc~l ~tsblLity wlll depond on ~uch factor~ ~ th~ n~lure of the futty l~cld, detergont nctlve compound, inor~nlc s~lta, especl~lly Tl P, other LADD Ingredlunts, n~ well 113 the nntlclp~ted stors~e und shlppln~ condltlon~.

Ceneruily, however, nmounta of the f~tty ncld thlxo~roplc s~ent thll~
cnn be u~ed nre In tho rnngo of from obout 0 . 0~ to 0 . 5~, prefer~bly rrom nbout o.oa to 0.2~, o~peclntly prafer~bly from obout 0.05 to 0.159~, prov1de tl~e ie~lred long torm stnblllty olld ~bscnco of phn~e sepurotlon.

T~u~ polyvn~ent metnl snit~ of the ubovo futty nclds cnn also bo used In th9 pre~ent Inventlon n8 thlxotroplc thlckener o~ent~. Sultnble metnl 6nlt 1 3 1 7 1 ~ 7 62301 ~520 thlxotroplc ~hlckener~ nre dlncloned In Can~dian appllcatton Sertnl No.
546,121 filed September 4th, 1987 in -the name of Drapier et al.
The preferred metDla nre ths poiyvnlent matnls euch as mngne~lum, cnlclum, nlumlnum nnd zlnc.
CenernJly, the metnls mQy be present In the dlvnlent to pentnvnlent stote. rrefernbly, tl-e metnl snlts nro used In thelr hJgher oxtdntlon stntes.
NDlurnlly, for LADD compo~ltlons, ns weli n~ nny other appllcatlons where 11la Inventlon compo~ltlon wlll or may come Into contnct wlth nrllcle~ used ror the handlln~, storMge or serv1ng of food productn or whlch otherwlse msy come Jnto contnct wt~h or be con~umed by people or nnlm~l3. the metnl ~nlt 3hould be selected by tnkln~ Into conslderntlon the toxlcity of the metnl. For thl~ purpose, the cnlclum nnd mngneslum snltn are especlQl!y hlghly preferred nn genernlly ~nfe f~od addlllveR.
Mnny of these metal snlt~ nre commerctnlly nvailable. For example, the nlumlnum saJts nre nvnilnble In the trincld form, e.g. nlumlnum stenrl3te n~
nlumlnum trlstenrate, Al(C17-H ~5C00)3. The monoacld 6alts, e.g. nlumlnum mono~tearate, AI~OH)2(C17H35COO) and dlacid ~nltn, e.g. nlumlnum dlstearnte, Al(OH)C17H35C00)2, nnd mlxtures of two or three of the mono-, di- nnd trl-ncld saltEJ cnn be used for those metnl0, e. g. ~1, with vnlences of +3, nnd mlxture~ of the mono- and dl-ncld snlts can be used for .
those metnl~, e.g. Zn, wJth valences of ~2. It i~ more preferred thut the dJnclds of the ~2 vnlent metnls nnd the trlHcld~ of the +3 vnlent metnls, the telrnaclds of the +4 metnln, nnd the pentnclds of the ~5 valent metals, be used In predomln~lnt nmounte. For exnmple, nt iea~t 30~, prefernbly n~
lenst 50~, e~peclnlly prefernbly from 80 to 100~ of the totnl metal snlt should be In the })Ighest po~slble oxldatlon ~tnte, I.e. encll of the possible vDlence sltes 1~ occupted by n fntty ncld resldue.
The metnl H~lt~, n~ mentloned nbove, nre genernlly commerclnlly avnllable but cDn be en~lly producad by, for exnmple, ~nponlflcnllon of n A

13171~7 Smectite clays include montmorillonite (bentonite), hectorite, attapulgite, smectite, saponite ~ and the like . Montmorillonite clays are preferred and are av~ilable under tradenames such as Thixogel ( Registered Trademark) No. 1 and Gelwhite (Regi3tered Trademark~ GP, H, etc., from Ceorgia Kaol~n Company; and Eccagum (Regl~tered Trademark) GP, H, etc., from Luthern Clay Products. Attapulgite clays include the materials commerci~lly available under the tradename Attagel (Regi~tered Trademarlc), i. e. Attagel 40, Attagel 50 and Attagel 150 from Engelhard Minersls and Chemicals ~orporation. Mixture~ of ~mectits and attapulgite types in weight ratiOQ o~' 4:1 to 1:5 are al~o useful herein. Thickening or suspending agents of the ~oregoing types are well known in the art, being described, for example, in U.S. Patent No. 3,985,668 referred to ~bove. Abrasives or polishlng agents should be avoided in th2 LADD composition~ as they may mar the surface of fine di~hware, crystal and the like.
When used in combination with the fatty acids or the fatty acid polyvalent metal salt3, thei clay thixotropic thickeners are used in amount~
of 0.1 to 3%, preferably Odl to 2.5% and more preferably in amount~ o~ 0.1 to29~, Wh~n the clay thixotropic thickeners are used alone as the thixotropic thickener agent they can be used in amounts of about 1.5 to 8%, preferably 2 to 5% by weight of the formulation.
C;enerally, LADD effectiveness i9 directly related to (a) available chlorine levels; (b) alkalinity; (c) solubility in washing medium; and (d) foam inhibition. It t8 preferred herein that the pH of the LADD composition be at least about 9.S, more preferably from about lO.S to 13.5 and niost preferably at least about 11. 5 . At the relatively lower pEI values, the LADD product i3 too vlscous, i. e . solid-like, and thus not readily Eluidized under the shear-force levels created within the dispenser cup under normal machine operating conditions. Addition of NaOH is thus often needed to increase the pH to within the above ranges, and to increase flowability 13171~7 properties. The presence of carbonate i~ also often needed h0rein, since it act~ as a buffer helping to maintain the desired pH level. Excess carbonate is to be avoided, however, since it may cause the formation of needle-like crystals of carbonate, thereby impairing the stability, thixotropy and/or S detergency of the LADD produ¢t, as well as impairing the dispensibility of the product from, for example, squeeze tube bottles. Caustic soda (NaOEI) serves the further function of neutralizing the phosphoric or phosphonic acid ester foam depressant when present . About 0 . 5 to 3 wt~ of NaOH antl about 2 to 9 wt% of sodium carbonate in the LADD composition are typical, although it should be noted that sufffcient alkalinity may be provided b~
the NATPP and sodium silicate.
The NaTPP may be employed in the LADD compositlon in a range of about 8 to 35 wt%, pre~erably about 20 to 3û wt~6, and should preferably be free of heavy metal which tends to decompose or inactivate the preferred sodium hypochlorite and other chlorine bleach compounds. The NaTPP may be anhydrou3 or hydrated ~ including~ the stable hexahydrate with a degree of hydration of ~ corre~ponding to about l8% by weight o~ water or more.
Actually, in view of the stability of the hexahydrste, the presence o~ some water o~ hydration is highly e~fective, servlng it is thought to form seed3 of the stable hexahydrate which expedite~ hydration and solubilization of the remaining NaTPP particles. If only the hexahydrate is used, the detergent product may be too liquid. Conversely, if only the anhydrous NaTPP i~ used, the product may, in some cases, be too thick and, therefore, unsuitable. Especially preferred LADD compositions are obtained, Ior example, when using a 0.5:1 to ~:1 weight ratio of anhydrous to hexahydrated NaTPP, values of about 1:1 being particularly preferred.
Foam inhibition i8 important to incresse dishwasher machine efficiency and minimize destabilizing effects whieh might occur due to the presence of exces~ foam within the washer during use. Foam rnay be sufficiently reduced by suitable selection of the type and/or amount of detergent active 13171~7 mnterial, the main foam-producing component. The degree of ~am is also somewhat dependent on the hardness of the wash water in lhe ma-~hine whereby ~uitable adjustment of the proportions of NaTPP which has a water softening effect may aid in providing the desired degree of foam inhibition.
However, it i8 generally preferred to include a chlorine bleach stable foam depressant or inhibitor. Particularly effective are the allcyl phosphonic acid esters of the formula li HO--P--R
0~
available for example ~rom BASF-Wyandotte (PCUK-PAE), and especially the alkyl acld phosphate esters of the formula ll HO--P --OR
OR
available, for example, from Hooker (SAP) and Knapsack tLPKn-158), in which one or both R groups in each type of ester may represent independently a Cl2_20 alkyl group. Mixtures of the two types, or any other chlorlne bleach stable type~, or mixtures of mono- and di-esters of the aame type, may be employed~ Especially preferred is a mixture of mono and di-C16-18 alkyl acid phosphate esters such as monostearylldistearyl acid phosphate~ 1.211 (Knapsack). When employed, proportions of 0.01 to 5 wt%, preferably 0.1 to 5 wt%, especially about 0.1 to 0. 5 wt%, of foam depressant in the composition i9 typical, the weight ratio of detergent active component (d) to foam depressant (e) generally ranging from about 10 :1 to 1:1 and preferably about 4 :1 to 1:1. Other defoamers which may be used include, for example, the known silicones.
Although any chlorine bleach compound may be employed in the compositiona of this invention, such as dichloro-isocyanurate, dichloro-dimethyl hydantoin, or chlorinated TSP, alkali metal, e . g.

13171~7 potassium, lithium, magnesium and especially sodium hypochlorite is preferred. The compositlon should contain sufficient chlorine bleach compound to provlde about O . 2 to 4 . 0% by weight of available ~hlorine, a~
determined, for example, by acidification of 100 parts of the composition with excess of hydrochloric acid . A solution containing about O . 2 to 4 . 0%
by weight of sodium hypochlorite contains or provides roughly the same percentage of available chlorine. A solulion containing about 0.8 to 1.6% by weight sodium hypochlorite contains about O . 8 to 1. 6% by weight of avail~ble chlorine and i8 especially preferred. For example, sodium hypochlorite (NaOCl~ solution of from about 11 to about 13% available chlorine in amount~
of about 3 to 20%, pre~erably about 7 to 12%, can be advantageously used.
The sodium silicate, which provide~ alkalinity and protection o~ hard 3urPace~, such as ~ine china glaze and pattern, iB employed in an amount ranging ~rom ~bout 2 . 5 to 40 wt%, preferably about 10 to 35 wt%, in the composition. At the higher Isvels specified herein for example at levels greater than about 10 wt% the silicate al~o provideq increased antispotting action. The sodium silicate i8 generally added in the form of an aqueou3 solution, pre~rably having an Na20:SiO2 ratio of about 1:2.2 to 1:2,8, for example, 1:2,4. Mo~t of the other componerlts of the composition, especially NaOH, sodium hypochlorite and foam depre~sant may also be added in the form o~ an Aqueous diqpersion or solution. .
Detergent active material u~eful herein must be stable in the presence of chlorine bleach, especially hypochlorite bleach, and those of the organic anionic, amine oxide, pho~phine oxide, sulphoxide or; betaine water 2 5 dispersible ~urfactant type~ are preferred, the first mentioned anionics being most preferred. They are used in amounts ranging from about 0.1 to 5% preferably about O . 3 to 2 . 0% . Particularly preferred surfactantq herein are the linear or br~nched alkali metal mono- andlor di-(C8 1~) alkyl diphenyl oxide mono nnd/or disulphates, commercially available for example a3 DOWFAX (Registered Trademark) 3B-2 and DOWFAX 2A-l.

~ 13171S7 In addition, the surfactant should be compatible with the other ingreàients of the composition. Other suitable surfactants include the i primary alkylsulphate~, alkylsulphonates, alkylaryl-sulphol~ates and l sec.-alkylsulphates. Examples include sodium C~ 3 alkylsulphate~ such as S ¦ sodium dodecylsulphate and sodium tallow alcoholsulphate; sodium C10 1~
ulkanesulphonates such a~ sodium hexadecyl-1-sulphonate and sodium C12 18 alkylbenzenesulphonates such as sodium dodecylbenzenesulphonates. The ¦ corresponding potassium salts may also be employed.
¦ A~ other suitable surfactants or detergent~, the amine oxide ¦ surfactants are typically of the structure R2R1NO, àn which each R
¦ represents a lower alkyl group, for instance, methyl, and Rl represents a ¦ long chain alkyl group having from 8 to 22 carbon atoms, for instance a ¦ lauryl, myristyl, palmityl or cetyl ~roup. Instead of an amine oxide, a ¦ corresponding surfactant phosphirle oxide R2E31PO or sulphoxide RR 50 can ¦ be employed. Bet~in0 3ur~act~nts are typically of the structure R2RlN -¦ R"COO, in which each R represents a lower alkylene grsup having from 1 ¦ to 5 carbon atoms. Specif~c exsmples of these surfactants are ¦ lauryl-dimethylamine o~Ade, myriatyldimethylamine oxide, the corresponding ¦ phosphine oxides and sulphoxide~, and the corresponding betaines, including dodecyldimethylammonium acetate, tetradecyldiethylammonium pentanoate, hexadecyl-dimethylammonium hexanoate e~nd the like. For biodegradability, the alkyl groups in these surfactants should be linear, and such compounds are preferred.
Surfactants of the foregoing type, all well known in the art, are described, for example, in U.S. Patents 3,985,668 and 4,271,030.
The amount of water contained in these compositions should, of course, be neither so high as to produce unduly low viscosity and fluid}ty, nor so low as to produce unduly high viscosity and low flowability, thixotropic propertie~ in either case being diminished or de~troyed. Such amount is 3 0 readily determined by routine experimentation in any particular instance, . 13171~7 generally rang~ng from about 25 to 75 wt%, pre~erably about 5û to 65 wt96.
The water should also be preferably deionized or softened. These amounts of water in the compo~ition include the water added as parts of ithe liquid solutions of other ingredients, but do no include bound water, for example that in NaTPP hexahydrate.
Other conventional ingredients may be included in these compositions in sm~ll amounts, generally less th~n about 3 wt%, such a~ per~ume 9 hydrotropic agents such as the sodium ben~ene, toluene, xylene and cumene sulphonates, preservatives, dyestuffs and pigments and the like, all of course being stable to chlorine bleach compound and high alkalinity (properties of all the components). Especially preferred for coloring are the chlorinated phthalocyanine~ and polysulphides of aluminosilicate which provide, respectively, pleasing green and blue tints.
The liquid ADD composition~ of this invention are rsadily employed in known manner for washing dishes, glasses, cups, eating utensils and the like in an automatic di~hwasher, provided with a sl~itable detergent d~spenser, in an Qqueous wash bath containing an effective amount of the compo~ition.

j~ 21 13171~7 In a preferred embodiment of the invention the aqueous liquid dishwaahing detergent composition i~ formulated using the below named ingredients .
~ Wei~ht Percent Alkal} Metal Tripolyphosphate 10-25 Sodium Silicate (47 . 5~) 20-~0 Silica Anti-filming Agent1-4 Polyacrylic Acid Polymer or Salt 3-12 Alakli Metal Carbonate (anhydrous3 2-8 Chlorine Bleach Stable, Water 13ispersible Organic Detergent Active Matelqal 0.5-3 Chlorine Bleach Stable Foam Depressant 0.10-3 Chlorine Bleach Compound 0 . 2-4 Fatty Acid Thixotropic Thickener 0.03-û.5 Sodium Hydroxide ~50%) 2-6 Balance Water The thixotropic a~ueous liquid automatic dishwashing detergent compositions of the present inventi~n can contain comtentional dishwashing detergent composition additives. The formulations can be prepared with commercially available solid powder bullders, and/or the ingredients can be mixed and the formulations ground to a desired particle size.
The invention may be put into practice in various ways and a number of ~pecific embodiments will be described to illustrate the invention with reference to the accompanying examples.
All amounts and proportionc: re~erred to herein ars percent by weight o~ the composition unles~ otherwise indicated.
The present invention ia ~urther illuatrated by the ~ollowirg exsmples.

2~

t 3 1 7 1 S7 62301-1520 Examplc 1 A thixotroplc squeoua llquid nutomntic dishwAshlng detergent composltlon la formulnted from the followlng ingredient~ in the nmounts ~peclflccl .
Co ponent WelFht Percent Delonlzed Wnter 24 . 05 Knnpsack*LPKN-158 Fonm Depressnnt( ~ 0.16 Sodium Hydroxlde (50%~ 5,00 Sodlum Cnrbonnte (nnhydrous) 5, 00 Sodlum Tripolypho~phala (anilydrous) ' 20,00 Sillcll Anti-fllmlng Agent(2) 2.5 Sodium polyacryl~te polymer bullder(3)(A,1.~ 8,0û
Stenric Acld Thlxotropic Thlckener 0, lû
Dowfnx 3E~-2 Sur~actnnt( ) 0,80 Sodium Hypochlorlta ( ll96) 9,10 S~dlum Silicate (1/2,23 - q7%) ?5.29 100, 00 (1) Mlxture of mono und dlstearyl (C16-Cla) alkyl euters of phosphorlc ncld, mole rntlo 1:1. 3, (2) Slllca Sylold 244 hns n partlcl~ slze of about 4 mlcrons nnd 19 UVAilnble from W R. Gr a ce _& Co, (3) Alcosperae 1;1~, nbout 200~ mw, llvallnble n~ u 40% solutlon.

(4) N(l mono- nnd dldecyl cllphenyl ether di~ulronntc (4S9~ solutlon).
The Ingredlents nre ndded to the waler generally in the order listed nnd gently stlrred until u homogeneo~ls mixture ~3 obtalned. The rormulntlon In te~ted by wnshing gln~swnre nnd dlshwllre nt n tempernture of 120F In hnrd water (30û ppm hurdness) In an nutomutlc dlshwnshlng mnchlne and the clenn nnd dried dlshes nre found to hnve no nppnrent film nnd very f~w apparent ~pota, *I rade-mark 62301-152~
13171~7 ExnmDle 2 A
In order to demonstrale the effect of addlng the 8illca alltl-fllmillg ngent formulntions nre prepared wlth nnd wlthout the aillca antl-fllmlng agent and are compared to n commercln~ly avallnble powder detergent composl t lon .
The composltlona are formulated to contuln the followlng Ingredlents.
A B C
Slllcn/ No S-lllca/ Slllca/No Compon0ntPo!~ncrylnte Polyncrylflte Polyacrylate Deloni2ed WAt~r 24 05~ff . ~5 3A2.05 Knapsack LPKN-158 Foam D2pras~ant 0.1~ D. l~ n 16 Sodlum llydroxide (50~) 5.00 5.00 5.00 Sodlum Cnrbonnte (Anhydroua) 5.00 5.00 5.00 Sodlum Trlpolyphosphnte (Anhyd~A~ou~) 20.D0 20.00 20.00 Slllca (Sylold 244) Antl-filmlng Agent 2.50 --- 2.50 Sodlum Polyacrylate Polymer( l) (A .1. ) 8.00 8.00 ___ Stearlc Acld Thlxotroplc Thickener 0.10 0.10 0.10 Dowfax 3B-2 Sur~actnnt 0.80 0.80 0.80 Sodium Hypochlorlte (11%) 9.10 9.10 9.10 Sodlum Sllicnte (1/2.23 - 47%) 25 2~25.29 25 29 100,00100.00 100.00 (1) Alcoaperae 149.

The In~redlents sro sdded to the wster generally in the order llsted nnd gently ~tlrred untll ~ homogeneous mixture ta obtnlned. The formulntlon la tested by w~ahlng gls~swnre at 120F in hnrd w~ter (300 ppm hardne~a) .
The three above formulatlon~ (A) (B) and (C) were tested ~nd compsred wlth n commercially sva~lable powder automntlc dlshw~her detergent formu~lltlon D. Thè formulationa wera tested In a Kenmore *Trade-mark .~ .

~ 1~`17107 ¦ automatic dishwasher using the procedure described in ASTMD 3566-79, ¦ except that only four cleaning cycles are used. The filming and spotting ¦ are evaluated according to the following ~cales:
¦ Film Ratin~ Scale 5 ¦ 1. Best, no apparent film ¦ 2. ~qlming slight, becoming apparent ¦ 3. Noticeable film, increasing ¦ 4. Continued increase OI significant film ¦ 5. Filming becoming exce~ive - 10 ¦ 8. Filming high, excessive buildup ¦ 7. Continued increa~e of exces~iYe film.
¦ Spot Rating Scale ¦ A. Be~t - no 9p~t9 ¦ B. Yery i~w spots apparent 15C. Di~tinct D. Significan~ coverage approximately 50%.
The result~ obtained are reported in the below Table 1.

Formulation Performance Rating Spot Film ~A~ Silica/Polyacrylate B 1-2 (B) No Silica/Polyacrylate B-C 5-6 (C~ Silica/No Polyacrylate B-C 2 (D) Commeroinl Powder Detergent B-C 3-4 fatty acid, e. g. animal fat, ~tearic acid, etc., or the corresponding fatty acid ester, followed by treatment with an hydroxide or oxide of the polyvalent metal, for example, in the case of the aluminum salt, with alum, alumina, etc.
Calcium stearate, i. e . calcium distearate, magnesium stearate, i . e .
magne~ium distearate, aluminum stearate, i.e. aluminum tristearate, and zinc stearate, i . e . zinc distearate, are the preferred polyvalent fatty acid salt stabillzers. Mixed fatty acid metal salts, such a3 the naturally occurring acids, e. gO coco acid, a~ well a~ mixed fatty acid3 resulting from the commercial manufacturing proces~ are also advantageously used as an inexpensive but effective source of the long chain fatty acid.
The amount of the fatty aci~ salt stabilizers to achieve the desired enhancement o~ physical stability will depend on 3uch factors a3 the nature o~ the fatty acid salt, the nature and amount of the thixotropic agent, detergent active compound, inorganie salts, especially TPP, other l.ADD
ingredients, a~ well as the anticipated storage and shippin~ conditions.
Generally, ho~vever, ~mount3 of the polyvalent metal fatty acid salt stabillzing agents in the range of from about 0 . 02 to 1%, preferably from about 0 . 06 to 0 . 8%, especially preferably from about 0 . 08 to 0 . 4%, provide the long term stability and absence of phase ~eparation upon standing or during transport at both low and elevated temperatures as are required for a commercially acceptable product.
There may also be used in the present invention the conventional inorganic thixotropic clay thickeners. The clay thickener~ may be used in small amount~ in combination with the fatty acid thickeners or in combination with fatty acld polyvalerlt metal salt thickener~. The clay thickeners, however, may be used by themselve~ as the thixotropic thickener~ .
The preferred clay thickeners comprise $he inorganic, colloid forming clays of smectite and/or attapulgite types.

Exnmple 3 1 3 l 7 1 P, 1 Thlxotroplc nqueous llcluld automntlc dlshwn~hlng detergent compoaltion3 nre formulnted from the followlng Ingredlenls In the nmounts specifled .
E F C
Sllica/ No Slllcu/ Slllcn/No ComponentPolyncrylate Polyncrylate Polyncrylnte Delonlzed Wnter 27 . 6429 . 64 32 64 Knnpssck LPKN-158 Fonm Depres~nnt0.16 0.16 0.16 Sodlum Hydroxlde t50~) 5.00 5.00 5.00 Sodlum Carbonnte (Anhydrous) S . 00 5 00 5 00 Sodlum SUlcate tlt2 3S - 43,5%)25.30 25.30 25.30 Sodlum Trlpolyphosphute (Anhydroua) 20.00 20,03 20,00 Slllcn An~l-filmlng Agent( ) 2.00 --- 2.00 Sodlum Polyucrylllte( )(A.l.~ 5.00 5.00 ---Dow~ax 3B-2 Sur~actant~ ) 0.80 0.80 0.80 Ste~ric Acld(4) ~.10 0.10 0.10 Sodlum Hypochlorite ~1190) 9 00 9.00 9 00 100.00 100.00 100.00 (1) Slllca (Hubor Zeo ~9) contslna about 19d nlumlna (AL203).
(2) LMW ~15 N nbout 9500 M~Y, nvailDbl~ U9 a 45~6 aolutlon ot nctive in gredlen t .
(3) Nn mono nnd dldecyl dlphenyl ether dlsulfonnte (45~ solution).
(4) Emersol 1:12 nv~llable from Eme1~y lndustries I~c.
The lnKredlenta are udded to the water genernlly In the order listed nnd stlrred untll a homogeneou~ mlxture i9 obtnlned. The formulntlons nre tested by wnshing glQssware at 130F in hnrd water (300 ppm hardness).
The two formuln~ions were tested nnd compnrecl to n commercial powder nutomntlc dlshwnsher detergent formulntlon H. The formulntlona were tested In a Kenmore nutomntlc dlshwnsher u91nE~ the procedure descr~bed In ASTMD
3566-7~ except thElt only four clennlng cycles were u~ed. The spottlng nnd fllmlnK ure evalunted ns In Exnmple 2 nnd the reaults obtnlned ~lre reported In below Tnble 2.

13171~7 62~01-152~) Perform~nce Ratlng ~ Fllm (1~) Slllcn/Polyncrylnte A 2 (F) No Slllcn/Polyacryluta A 4 (C) Slllca/No Polyacrylate B 2-3 (H~ Commerelal Powder DetergentE~-C 5-6 Exnmple 4 A thlxotrople aqueou~ IJquld automatie dl~hwashlng datergent composl~lon Is formulated from tho followlng Ingredlent~ In thn amounta specifled .
C:omponent Wei~ht Percent Delonlzed Water 34.79 Alumlnum Stearut~ Thlxotrople Th;ekener 0. 25 Cluy (Phnrmugel ll) Thlxotrople Thlek~ncr 1.25 Sodlum Sllleate (1/2.9 - 47.596) 13.73 Sodlum Trlpolypho3phata (anhydrou~) 12.00 Sodlum Trlpolypho~ph~ta (hexnhydrate) 12.00 Slllca ~ntl-fllmlng Agent 2.00 Sodlum Polyacrylntc (MW 2000) 6 . 00 Sodlum Cnrbonnte (anhydr~us) 7.00 Sodlum ~Iypochlorite (11~)7.61 Dowfax 3B-2 Surfaetunt o,ao Knnpsack LPKN-158 Foam Depre3sant 0,16 Sodlum Hydroxlde (50~d) a.40 Graphltol Green .l 100.00 The Ingredlents urn mlxed following tlle procedur~ of the Canadian commonly nsslgned appllcatlon Serlal No- 546,121 filed September 4th, 1987 .

~ , :.
, . ~ .

13171~7 The formulation i8 tested by washing glassware at 130F in hard water (300 ppm hardness) in an automatic dishwashing machine. The cleaned and dried glassware are found to have no apparent f~lm and very few apparent spot~.
The thixotropic aqueous liquid automatic dishwashing detergent compo~itions of the present lnvention provide improved film properties.
The invention is not to be limited by the above disclosure and Examples which are given as illustrations only. The invention is to be interpreted in accordance with the below claims.

Claims (22)

1. A gel-like thixotropic aqueous liquid automatic dishwashing detergent composition comprising water, at least one ingredient selected from the group consisting of organic detergent, chlorine bleach, detergent builder, sequestering agent, foam inhibitors, and mixtures thereof, from about 0.5 to 5% of a silica anti-filming agent and about 2 to 14% of a polyacrylic acid polymer or salt, and a sufficient amount of a thixotropic thickener to provide a thixotropic index of about 2.5 to 10.

2. The composition of claim 1 wherein the silica anti-filming is in an amount of about 1 to 4% and the polyacrylic acid polymer or salt is in an amount of about 3 to 12%.

3. A thixotropic aqueous liquid automatic dishwasher composition comprising approximately by weight:
(a) 5 to 35% detergent builder;
(b) 2.5 to 40% sodium silicate;
(c) 0.5 to 5% of silica anti-filming agent having a particle size of about 0.1 to 10 microns;
(d) 2 to 14% polyacrylic acid polymer or salt builder having a molecular weight of 1000 to 100,000;
(e) 0 to 9% alkali metal carbonate;
(f) 0.1 to 5% chlorine bleach stable, water-dispersible organic detergent active material;
(g) 0 to 5% chlorine bleach stable foam depressant;
(h) chlorine bleach compound in an amount to provide about 0.2 to 4% of available chlorine;
(i) a sufficient amount of a thixotropic thickener to provide a thixotropic index of about 2.5 to 10.
(j) 0 to 8% of sodium hydroxide;
(k) balance water.

I

4. The composition of claim 3 wherein the polyacrylic acid polymer or salt has the formula wherein R1, R2 and R3 can be the same or different and can be hydrogen, C1-C4 lower alkyl, M represents hydrogen, or an alkali metal, n = 5 to 1000 and the polymer has a molecular weight of 1000 to 100,000.

5. The composition of claim 3 wherein the thixotropic thickener comprises a long chain fatty acid in an amount of about 0.03 to 0.5%.

6. The composition of claim 3 wherein the thixotropic thickener comprises a polyvalent metal salt of a long chain fatty acid in an amount of about 0.02 to 1.0%.

7. The composition of claim 5 additionally comprising a clay thixotropic thickener in an amount of about 0.1 to 3.0%.

8. The composition of claim 6 additionally comprising a clay thixotropic thickener in an amount of about 0.1 to 3.0%.

9. The composition of claim 3 wherein the silica anti-filming agent has a particle size of about 0.5 to 8.0 microns.

10. A thixotropic aqueous liquid automatic dishwasher composition comprising approximately by weight:
(a) 5 to 35% alkali metal tripolyphosphate;
(b) 2.5 to 40% sodium silicate;
(c) 1 to 4% silica anti-filming agent having a particle size of about 0.5 to 8.0 microns;
(d) 3 to 12% polyacrylic and polymer or salt builder;
(e) 0 to 9% alkali metal carbonate;
(f) 0.1 to 5% chlorine bleach stable, water dispersible organic detergent active material;
(g) 0 to 5% chlorine bleach stable foam depressant;

(h) chlorine bleach compound in an amount to provide about 0.2 to 4% of available chlorine;
(i) a sufficient amount of a thixotropic thickener to provide thixotropic index of about 2.5 to 10.
(j) 0 to 8% of sodium hydroxide;
(k) balance water.

11. The composition of claim 10 wherein the polyacrylic acid polymer or salt has the formula wherein R1 and R3 are hydrogen, and R2 is hydrogen or methyl, M
represents hydrogen, sodium or potassium, n = 10 to 500 and the polymer has a molecular weight of 1500 to 50,000.

12. The composition of claim 10 wherein the polyacrylic acid polymer or salt has a molecular weight of about 2000.

13. The composition of claim 10 wherein the polyacrylic acid polymer or salt has a molecular weight of about 4500.

14. The composition of claim 10 wherein the silica anti-filming agent contains about 0.1 to 5% of alumina, based on weight of silica.

15. The composition of claim 10 wherein the silica has a particle size of about 1 to 5 microns.

16. The composition of claim 10 wherein the thixotropic thickener comprises a long chain fatty acid having C16 to C20 carbon atoms in an amount of about 0.03 to 0.20%.

17. The composition of claim 10 wherein the thixotropic thickener comprises a polyvalent metal salt of a long chain fatty acid having C16 to C20 carbon atoms in an amount of about 0.06 to 0.8%.

18. The composition of claim 17 wherein the polyvalent metal is one of aluminum, calcium, zinc and magnesium.

19. The composition of claim 16 additionally comprising a clay thixotropic thickener in an amount of about 0.1 to 2.5%.

20. The composition of claim 17 additionally comprising a clay thixotropic thickener in an amount of about 0.1 to 2.5%.

21. A method for cleaning soiled glassware and dishware in an automatic dishwashing machine which comprises contacting the soiled dishware in an automatic dishwashing machine in an aqueous washbath having dispersed therein an effective amount of the composition of claim 3.

22. A method for cleaning soiled dishware in an automatic dishwashing machine which comprises contacting the soiled glassware and dishware in an automatic dishwashing machine in an aqueous washbath having dispersed therein an effective amount of the composition of claim 10.