AU8522598A - Machine dish washing composition - Google Patents

Description

r4.

ii I c

AUSTRALIA

PATENTS ACT 1990 rr r

ORIGINAL

COMPLETE

SPECIFICATION

STANDARD

PATENT

.o TITLE OF INVENTION s r c MACHINE DISH WASHING

COMPOSITION

Name and Address of Applicant: UNILEVER PLC of UNILEVER HOUSE, BLACKFRIARS, LONDON EC4P 4BQ, ENGLAND The following statement is a full description of this invention, including the best method of performing it known to me:r;

I--

C3802 1 Machine Dish Washing Composition The present invention lates to a tablet for use in a dish washing machine, a methcd of preparing the tablet and packaging for the tablet.

Background of the Invention Detergent tablets for dish-washing machines are ilked by consumers as they find them are more convenient to use than S alternative products such as powders and the like.

SHowever detergent tablets frequently exhibit poor dissol ibon rates in the washing water of the machine, this poor dissolution can make it necessary for the consumer to operate consecutive rinses which is time consuming.

Another problem that is faced is based on the fact that the detergent tablets for dish-washing machines contain fo ul,,ations hich are aggressive to the users' skin.

Tablets for machine dishwashing are described in EP-A-224,1 28 EP-A-224,13 5 EP-A-224,1 36 WO-91/15568, and EP-A-26, 47 0 All the prior art primarily deals with traditional high pH formulations and suggests routes to improving the performance of tablets which basically rely on modifying the solubility profiles of the tablets.

30 Powder flowability is an important factor to consider in the manufacture of a tablet. Powders with a low flowability k (less than 50 ml/s) can have two negative aspects namely: M C3802 2 they can compact at the press feed line reducing throughput and they do not flow at a rate which is compatible with the pressing cycle and thus do not completely fill the tablet forming mold.

the smooth finish of the tablet.

Manufacture of tablets can also be difficult due to :difficulty in ejecting the tablet from a mold.

This difficulty means that the mechanical wear on the S 15 tabletting machine is increased and may flaws can occur on the tablet's surface To achieve tablets that are easy to process and quick to dissolve detergent tablets may contain binding and disintegrating agents.. An important property of these such agents is that th ey are compatible with the active ingredients in the tablet. Frequently an agent can have a Sdual role a bininng agent also acts as a disintegrating agent.

fervescent systems have been included in a tablets formulation to increase their dissolution rate. Such effervescent systems includes weak acids or acid salts such as citric acid, maleic acid, sodiumand hydrogen phosphates, in combination with a basic ingredient that liberates carbon dioxide when interacting.with this source of acid. Examples include sodium and potassium carbonate and bicarbonate and -sodium sesquicarbonate. **clud s .k .s -7 *fe veA A as 1 i ri C3802 3 Description of the Invention The present invention relates to a tablet that dissolves rapidly when added to water and is easy to manufacture accordingly the present invention relates to a machine dish washing tablet comprising a bleaching system, a silicone and less than 10 wt% of surfactant.

The invention also relates to a process for preparing machine dish washing tablets comprising the step of adding a S; silicone emulsion to a formulation that is to be tableted.

The invention also relates to a dish washing tablet(1) and a packaging system the packaging system comprising a body shaped to receive a tablet and a cover(4) which keeps the tablet in the body. The use of this packaging system to store dish washing tablet is also described.

Detailed description of the Invention S The tablets according to the present invention not only dissolve quickly in the dish washing machine but they are easy to process in that the powder used to manufacture the tablets has good flowability, does not adhere to the punch's surface and the tablets produced are easily ejected from the mold.

Additionally the tablets of the invention can be prepared by conventional presses instead of powerful presses which are commonly used to for making detergent tablets.

Conventional presses are those with engines with up to Sa sole compression stage with a working capacity of up to C3802 4 12t/cmL and production rate of 18000 tablets per hour. The cost of these presses is up to 8 times smaller than the double-stage large presses with a high pressing rate normally used to prepare detergent tablets.

Silicones The tablets of the invention comprise a silicone, preferably in the form of an emulsion.

I The addition of water to the tablet via the emulsion is beneficial because it can prevent the powder from granulating. The granulation of the powder to from granules S 15 greater than 10mm is undesirable because it causes difficulties when press feeding press feeding.

The silicones used are preferably polymers or copolymers of dimethyl silicone or aminomethoxy functionalised dimethyl S 20 silicone. Mixtures of the polymers may also be used.

r: It is preferable if the level of silicone emulsion added to the product is from 0.5 wt% to 10 wt% of the total product, preferably from 1 to 3 wt%.

*It is also preferable if the level of silicone within the silicone emulsion is from 2 wt% to 50 wt% of the total weight of the silicone emulsion, preferably from 5 to wt%.

To emulsify the silicone in water any emulsifier may be Sused, preferably the emulsifier is a surfactant, most preferred as the emulsifier a nonionic surfactant.

C3802 The silicone emulsions preferentially used in the present invention are those available from Dow Corning under the trademarks Dow.Corning 36, 346, and 347; Dow Corning HV-490, Dow Corning 190 and 93; Dow Corning 531 and 536; Dow Corning 8075, 7242, Dow Corning 2-8707 and OSI-SAG 470, Bleaching Systems The bleaching systems of the invention are preferably oxygen based.

Peroxy Bleaching Agents The oxygen bleaching agents of the compositions include organic peroxy acids and diacylperoxides. Typical monoperoxy acids useful herein include alky! peroxy acids and aryl peroxy acids such as: I) peroxybenzoic acid and ring-substituted peroxybenzoic acids, peroxy-alpha-naphthoic acid, and magnesium monloperoxyphthalate ii) aliphatic and substituted aliphatic monoperoxy acids, peroxvlauric acid, peroxyStearic acid, epsilon-phthalimido-perox~yhexanoic acid and o-carboxybenzamfido peroxyhexanoic acid, Nnonyla-nidoPeradipic acid and N-nonylafidopersucciflic acid.

iii) Cationic peroxyacids such as those described in US-A- 5,422,028, US-A-5,294,3 62 and US-A-5,292, 447 iv) Sultoflyl peroxyacids such as compounds described in US- A-5,039, 447 (Monsanto Co.).

C3 802 -6lypical diperoxy acids useful herein include a2lkYll diperoXcY acids and aryl- diperOxy acids, Such as: v) 1,12 -dipetoxydodecanedio- acidt vi) l 9 -diperoxyazelaic acid sc~cai n vii) diperoxybrass~iic acdl ieyeaic acidan diperOxY-isophtha 14-i acid iii') 2 -decyldiperoxybutan 4d~Cai ix)NIhtrthaloyl-di (6aioecpO acid).tyia iclperoxide useful herein includes dibeflzOylperoxide.

~~ogali pr~ygn omounds ar seilYsuitable for: 15 Iheoreentc invxenin COOP ll fthsmaerials useful .in the invention are salts of ydrapersunfaterprboate. l monohydrate, perboratettahrte anprcbnt.

sodi... eboteadodium percarbonate are particularl preferred.

20 ti h OPstO na The organic peroxy acid is present inte coidion thea am~ut sch tat he evel Of organic peroxyacdith ashun sllir i1pmto30 ppm AvOX, preferably 2 pmt 200 pm vOC. Typcallevels of organic eoYai r 425 from 2 wt% to 15 wt% oftettlfruain Th oxgen~leahifg aentmay be incorporated directly into the formulatiol or may be encapsulated by any number ofencapsulation techniques- Bleach Precursors Suitable peracid precursors for peroxy bleach compounds b been amply described in the literature, including GB Nos.

836,988; 855,735; 907,356; 907;358; 907,950; 1,003,310 arid 1,246,339; US-A-3,332,882 and US-A-4,128,494.

TIypical examples of precursors are polyacylated alkylene diamines, such as N,N,N',Ns-tetraacetylethylene diaxnine (TAED) and N,,'N-eractlehjn diamine

(TAMD);

acylated glycolurils, such as tetraacetylglycoluril

(TAGU);

triacetylcyanurate, soiu sulfophenyl ethyl carbonic acid ester, sodium acetyloxybenene sulfonate (SABS)1, sodium 15 nonanoyloxy benzene sulfonate (SNOBS) and choline sulfophenyl carbonate. Peroxybenzoic acid precursors are **known in the art, as described in GB-A-836,988- Examples of suitable precursors are phenylbenzoate; phenyl o-nitrophenyl benzoate; o-carboxyphenyl benzate p-rompheylbnzote;sodium or potassium benzoyloxy benzene-sulfonate; and benzoic anhydride., Preferred peroxygen bleach precursors are sodium pbenzoyloxybenzene sulfonate, NL,'N-eraeyehln diamine, sodium nonanoyloxybenzene sulfonate and choline sulfophenyl carbonate. The peroxygen bleach precursors may *be present in the composition in an a-mount from 1 to 20 wt.

preferably from 1 to 15 wt. most preferably from 2 to weight To deliver a functional peroxygen bleach from a precursor, a source of hydrogen peroxide is required. The hydrogen peroxide source is preferably a compound that *delivers hydrogen peroxide on dissolution. Preferred sources of hydrogen peroxide are sodium perborate, either as mono- or tetrahydrate and sodium percarbonate- The source C3802 of hydrogen peroxide, when included in the composition, is present at a level from 1% to 30% by weight, preferably from 2W to 25% by weight, most preferably from 4% to 20% by weight.

Bleach Catalyst An effective amount of a bleach catalyst can also be present in the first layer- A number of organic catalysts are available such as the sulfonimines as described in US-A- 5,041,232; US-A-5,047,163 and US-A-5,463,115.

Transition metal bleach catalysts are also useful especially those based on manganese, iron, cobalt, titanium, nickel, chromium, copper, ruthenium, tungsten and mixtures thereof. These include simple water-soluble salts such as those of iron, manganese and cobalt as well as catalysts containing complex ligands.

20 Suitable examples of manganese catalysts containing organic ligands are described in US-A-4,728,455, US-A-5,114,606,

US-

A-5,153,161, US-A-5,194,416, US-A-5,227,084, US-A-5,244,594, 04~ US-A-5,246,612, US-A-5,246,621, US-A-5,256,779,

US-A-

5,274,147, US-A--5,280,117 and EP-A-544,440, EP-A-544,490, EP-A-549,271 and EP-A-549,272. Preferred examples of these catalysts include Mn~jv 2 (u-o) 2 4,7-trimethyl-l,4,7triazacyclononane) 2 (Pp 6 2 Mn' 4 .(u-O)I(U-OAc) 2 CL,4,7-~ trimethy-l-1,4,7-triazacvclononane)2(CI0 4 2 MnIV 4 (u-O) 6 (1l,4,7triazacyclononane) 4

(CIO,)

4 Mfl"'Mnlv4(u-O) 1 (u-OAc) 2 (1,4,7trimethyl-1,4,7triazacyclononane) 2

(CO

4 Mn"(1,4,7t.rimethyl-l, 4, 7-triazacyclononane) C3802

(,OCH

3 3 and mixtures thereof. other metal-based bleach catatysts include those disclosed in uS-A-4,43 0 243 and US- A-5,,1!4,611.

r-on and manganese salts of aminocarboxylic acids in general are useful herein including iron and manganese arn-inocarboxylate salts disclosed for bleaching in the photographic color processing arts. A particularly useful transition metal salt is derived from ethylenediamifledisuccinate and any complex of this ligand with iron or manganese.

~.:Another type of bleach catalyst, as disclosed -in US-A- 5,114,606 is a water soluble complex of manganese (11), .2 (ITT), and/or (IV) with a ligand which'is a non-carboxylate 15 polyhydroxy compound having at least three consecutive

C-OH

groups. Preferred ligands include sorbitol, iditol, dulsitol, inannitol, xylithol, arabitol, adonitol, _rnesoerythritol, meso-inositol, lactose and mixtures thereof.

Especially preferred is sorbitol.

US-A-5,114, 6 ll teaches a bleach catalyst comprising a complex of-transition metals, including manganese, cobalt, iron or copper with an non- (xacro)-cyclic ligand- Other examples include Mn gluconate, M1n(CF 3 SO3h2, and binuclear Mn complexed with tetra-N-defltate and bi-N-dentate ligands, including [biPY 2 Mn' (uO) 2 Mn iyl- C0) Other bleach catalysts are described, for example, in EP-A- 1 408,131 (cobalt complexes), EP-A-384,50 3 and EP-A-306,O 8 9 (metallo porphyrifl5), US-A-4,728, 4 5 5 (miangaflese/m~ltideflate ligand), US-A-4,711, 7 4 8 (absorbed manganese on aluninosilicate), US-A-4,601, 8 4 5 (aluminosilicate support with manganese, zinc or magnesium salt), US-A-4,626,3 7 3 C3802 (manganese/ligand), US-A-4,119,55 7 (ferric complex), US-A- 4,430,243 (Chelants with manganese cations and non-catalytic metal cations), and US-A-4,728,455 (manganese gluconates).

Useful catalysts based on cobalt are described in W096/23859, W096/23860 and W096/23861 and US-A-5,559,261.

WO 96/23860 describe cobalt catalysts of the type [COnLmXp]Yz, where L is an organic ligand molecule containing more than one heteroatom selected from N, P, 0 and S; X is a co-ordinating species; n is preferably 1 or 2; m is preferably 1 to 5; p is preferably 0 to 4 and Y is a counterion. One example of such a catalyst is N,N'- Bis(salicylidene)ethylenediaminecobalt Other cobalt catalysts described in these applications are based on S 15 Co(III) complexes with ammonia and mon-, bi-, tri- and *tetradentate ligands such as [Co(NH 3 5 OAc] 2 with Cl-, OAc-, PF6-, SO 4 BF4- anions.

Certain transition-metal containing bleach catalysts can be prepared in the situ by the reaction of a transition-metal salt with suitable chelating agent, for example, a mixture of manganese sulfate and ethylenediaminedisuccinate. Highly colored transition metal-containing bleach catalysts may be co-processed with zeolites to reduce the color impact.

When present, the bleach catalyst is typically incorporated *at a level of 0.0001 to 10% by wt., preferably 0.001 to by weight.

i r -7 C3802 11 Detergent Builder Material The compositions of this invention can contain all manner of detergent builders commonly taught for use in machine dishwashing or other cleaning compositions. The builders can include any of the conventional inorganic and organic water-soluble builder salts, or mixtures thereof and comprise 5 to 90% by weight, preferably from 10 to 80% by weight of the cleaning composition.

Typical examples of phosphorus-containing inorganic S:builders, when present, include the water-soluble salts, Sespecially alkali metal pyrophosphates, orthophosphates and polyphosphates. Specific examples of inorganic phosphate S 15 builders include sodium and potassium tripolyphosphates, 0pyrophosphates and hexametaphosphates.

Suitable examples of non-phosphorus-containing inorganic builders, when present, include water-soluble alkali metal 20 carbonates, bicarbonates, sesquicarbonates, borates, silicates, including layered silicates such as SKS-6 ex.

Hoechst, metasilicates, and crystalline and amorphous alumiinosilicates. Specific examples include sodium carbonate (with or without calcite seeds), potassium carbonate, sodium and potassium bicarbonates, silicates including layered silicates and zeolites.

SOrganic detergent builders can also be used in the present 1: invention. Examples of organic builders include alkali metal citrates, succinates, malonates, fatty acid sulfonates, fatty acid carboxylates, nitrilotriacetates, I phytates, phosphonates, alkanehydroxyphosphonates, oxydisuccinates, alkyl and alkenyl disuccinates, _Y~rpP~alp~mammonismp C3802 -12oxydiacetates, carboxymfethYlOXY succiflates, ethylenedi.amine tetraacetates, tartrate monoSucciflates, tartrate disuccinates, tartrate monoacetates, tartrate diacetates, oxidized starches, oxidized heteropolymeric polysaccharides, 5 polyhydroxysulfoflates, polycarboxylates such as polyacrylateS, polytnaleates, polyacetates, polyhydroxyacrylates, polyacrylate/polYmaleate and polyacrylate! polymethacrylate copolymners, acrylate/maleatelvinyl alcohol terpolyfers, aminopolycarboxylates and polyacetal carboxylates, and polyaspartates and mixtures thereof. Such carboxylates are described inUS-A-4, 144,226, US-A-4,l4 6 495 and US-A- 4,686,062.

J 15 Alkali metal citrates, nitrilotriacetates, oxydisuccilates, pclyphosphoflates, acrylate/maleate copolymfers and acrylate/mfaleate/viflYl alcohol terpolymfers are especially p referred organic builders.

2 0 Bfeig Ss aThe buffering system may be present in order to deliver a pH of about 6 to about 11 in the wash water. Materials which may be selected for the buffering system include water-soluble alkali metal carbonates, bicarbonates, sesquicarbolates, borates, silicates, layered silicates such as SKS-6 ex Hoechst, metasilicates, phytiC acid, citric acid, borate and crystalline and amorphous alulninosilicates and mixtures thereof. Preferred examples include sodium and potassium carbonate, sodium and potassium bicarboflates, borates and silicates, including layered silicates "ME~ elm C3802 13 SSurfactants Optionally a surfactant may be included in the tablet including anionic, nonionic, cationic, amphoteric, zwitteronic surfactants and mixtures of these surface active agents. However the total level of surfactant in the tablet must not exceed 10% by weight of the total weigh of the tablet. Such surfactants are well known in the detergent arts and are described at length at "Surface Active Agents and Detergents", Vol. 2 by Schwartz, Perry and Birch, i Interscience Publishers, Inc., 1959, herein incorporated by reference.

Sreferred surfactants are one or a mixture of: Anionic surfactants ae SAnionic synthetic detergents can be broadly described as surface active compounds with one or more negatively charged 20 functional groups. An important class of anionic compounds are the water-soluble salts, particularly the alkali metal salts, of organic sulfur reaction products having in their .molecular structure an alkyl radical containing from about 6 to 24 carbon atoms and a radical selected from the group consisting of sulfonic and sulfuric acid ester radicals.

Primary Alkyl Sulfates R OSO 3

M

where R' is a primary alkyl group of 8 to 18 carbon atoms and M is a solubilizing cation. The alkyl group Ra may have a mixture of.chain lengths. It is preferred that at least two -thirds of the R' alkyl groups have a chain length of 8 to 14 IS ~iin. 11 V^ C3802 S14 carbon atoms. This will be the case if R 1 is coconut alkyl, for example. The solubilizing cation may be a range of cations which are in general monovalent and confer water solubility. Alkali metal, notably sodium, is especially envisaged. Other possibilities are ammonium and substituted ammonium ions, such as trialkanolammonium or trialkylammonium.

Alkyl Ether Sulfates RO (CHzCHzO) nSO 3

M

o where R' is a primary alkyl group of 8 to 18 carbon atoms, n has an average value in the range from 1 to 6 and M is a solubilizing cation. The alkyl group R' may have a mixture of chain lengths. It is preferred that at least two thirds of the R' alkyl groups have a chain length of 8 to 14 carbon atoms. This will be the case if R' is coconut alkyl, for example. Preferably n has an average value of 2 to Fatty Acid Ester Sulfonates R CH (SO 3 M) C0 2

R

3 where R 2 is an alkyl group of 6 to 16 atoms, R 3 is an alkyl group of 1 to 4 carbon atoms and M is a solubilizing cation.

The group R 2 may have a mixture of chain lengths. Preferably at least two thirds of these groups have 6 to 12 carbon atoms. This will be the case when the moiety R2CH(-)C02(-) is derived from a coconut source, for instance. It is preferred that R' is a straight chain alkyl, notably methyl or ethyl.

I:

C3802 Alkyl Benzene Sulfonates

R

4 ArSO 3

M

where R 4 is an alkyl group of 8 to 18 carbon atoms, Ar is a Sbenzene ring (C 6

H

4 and M is a solubilizing cation. The group R may be a mixture of chain lengths. Straight chains of 11 to 14 carbon atoms are preferred.

Paraffin sulfonates having 8 to 22 carbon atoms, preferably S12 to 16 carbon atoms, in the alkyl moiety. These surfactants are commercially available as Hostapur SAS from SHoechst Celanese.

Olefin sulfonates having 8 to 22 carbon atoms, preferably 12 to 16 carbon atoms. U.S. Patent No. 3,332,880 contains a description of suitable olefin sulfonates.

Organic phosphate based anionic surfactants include organic 20 phosphate esters such as complex mono- or diester phosphates of hydroxyl- terminated alkoxide condensates, or salts thereof. Included in the organic phosphate esters are phosphate ester derivatives of polyoxyalkylated alkylaryl phosphate esters, of ethoxylated linear alcohols and ethoxylates of phenol. Also included are nonionic alkoxylates having a sodium alkylenecarboxylate moiety Slinked to a terminal hydroxyl group of the nonionic through an ether bond. Counterions to the salts of all the Sforegoing may be those of alkali metal, alkaline earth metal, ammonium, alkanolammonium and alkylammonium types.

v -I *'y C3 802 -16 Particularly preferred anionic surfactants are the fatty acid ester sulfoflates with formula: R 2 CH (SOJM)

CO

2 R3 where-the moiety R'CH()C02(-) is derived from a c 0 oconut source and R is eit her methyl or ethyl; primary alkyl sulfates with the formula: 10 R'OSO3M 100 0t w~rein.' isa primary lkylgroup of 10 to 18 carbon atoms :0 arid m4 is a sodium~ cation; and paraf fin sulfoflates, preferably with 12 to 16 carbon atost h ly oey ,.o*Nonionlic surfatants Nonionic surfactants can be broadly defined as surface active compounds with one or more uncharged hydrophilic 20subst3ituents. A major class of nonionic surfactants are those compounds produced by the condensation of alkylene :...oxide groups with an organic hydrophobic material which may be aliphatic or alkyl aromatic in nature. The length of the hydrophilic or polyoxyalkylene radical which is condensed with any Iparticular hydrophobic group can be readily adjusted to yield a water-soluble compound having the desired degre-e of balance between hydrophilic- and hydrophobic elements. Illustrative, but not limiting examples, of various suitable nonionic surfactant types are: poyoy~kZ~ ondensates of aliphatic carboxyic acids, U'whether linear- or branched-chain and unsaturatedo4 saturated, eseill thxlae and/or propoxylated' C3802 17 aliphatic acids containing from about 8 to about 18 carbon atoms in the aliphatic chain and incorporating from about 2 to about 50 ethylene oxide and/or propylene oxide units.

Suitable carboxylic acids include "coconut" fatty acids (derived from coconut oil) which contain an average of about 12 carbon atoms, "tallow" fatty acids (derived from tallow-class fats) which contain an average of about 18 carbon atoms, palmitic acid, myristic acid, stearic acid and lauric acid, polyoxyalkene condensates of aliphatic alcohols, whether linear- or branched-chain and.unsaturated or saturated, especially ethoxylated and/or propoxylated aliphatic alcohols containing from about 6 to about 24 carbon atoms and incorporating from about 2 to about 50 ethylene oxide and/or propylene oxide units. Suitable alcohols include "coconut" fatty alcohol, "tallow" fatty alcohol, lauryl alcohol, myristyl alcohol and oleyl alcohol.

20" Ethoxylated fatty alcohols may be used alone or in admixture with anionic surfactants, especially the preferred surfactants above. The average chain lengths of the alkyl group R5 in the general formula:

R

5 0 (CH 2

CH

2 0)nH is from 6 to 20 carbon atoms. Notably the group R 5 may have I chain lengths in a range from 9 to 18 carbon atoms.

The average value of n should be at least 2. The numbers of ethylene oxide residues may be a statistical distribution around the average value. However, as is known, the Sdistribution can be affected by the manufacturing process or C3802 B 18altered by fractionation after ethoxylation. Particularly preferred ethoxylated fatty alcohols have a group R 5 which has 9 to 18 carbon atoms while n is from 2 to 8.

Also included within this category are nonionic surfactants having a formula: Rs--(C HCHO),(CH C H)y(CH,CH )zH 1 wherein

R

6 is a linear alkyl hydrocarbon radical having an average of 6 to 18 carbon atoms,

R

7 and R 8 are each linear alkyl hydrocarbons of about 1 to about 4 carbon atoms, x is an integer of from 1 to 6, y is an integer of from 4 to and z is an integer from 4 to One preferred nonionic surfactant of the above formula is Poly-Tergent SLF-18 7 a registered trademark of the Olin Corporation, New Haven, Conn. having a composition of the above formula where R 6 is a C 6 -CIo linear alkyl mixture,

R

7 and R 8 are methyl, x averages 3, y averages 12 and z averages 16. Another preferred nonionic surfactant is R me(CH,CHe(CH,CH,H,H,(CHCH(OH)RI"), wherein R' is a linear, aliphatic hydrocarbon radical having from about 4 to about 18 carbon atoms including mixtures thereof; and R 0 is a linear, aliphatic hydrocarbon radical C3802 19 having from about 2 to about 26 carbon atoms including mixtures thereof; j is an integer having a value of from 1 to about 3; k is an integer having a value from 5 to about and z is an integer having a value of from 1 to about 3.

1 5 Most preferred are compositons in which j is 1, k is from about 10 to about 20 and 1 is 1. These surfactants are described in WO 94/22800. Other preferred nonionic surfactants are linear fatty alcohol alkoxylates with a capped terminal group, as described in U.S. 4,340,766 to BASF. Particularly preferred is Plurafac LF403 ex. BASF.

Another nonionic surfactant included within this category are compounds of formula: Ri--(CHaCH,O)qH wherein R" is a C 6

-C

24 linear or branched alkyl hydrocarbon radical and q is a number from 2 to 50; more preferably

R"

is a Cs-C 8 linear alkyl mixture and q is a number from 2 to polyoxyethylene or polyoxypropylene condensates of alkyi phenols, whether linear- or branched-chain and unsaturated or saturated, containing from about 6 to 12 carbon atoms and incorporating from about 2 to about 25 moles of ethylene oxide and/or propylene oxide.

polyoxyethylene derivatives of sorbitan mono-, di-, and tri-fatty acid esters wherein the fatty acid component has between 12 and 24 carbon atoms. The preferred polyoxyethylene derivatives are of sorbitan monolaurate, 30 sorbitan trilaurate, sorbitan monopalmitate, sorbitan tripalmitate, sorbitan monostearate, sorbitan monoisostearate, sorbitan tripalmitate, sorbital IS C3 802 tristearate, sorbitan monooleate, and sorbitan trioleate.

The polyoxyethylele chains may contain between about 4 and ethylene oxide units, preferably about 10 to 20. The sorbitan ester derivatives contain 1. 2 or 3 polyoxyethylene chains dependent upon whether they are mono-, di- or tni-acid esterspolyoxyet hyl ene-polyoxypropyI ene block Copolymfers having formula: *HO

(CI

2

CH

2 0)aI(CH (CH3)

CH

2 0) b(CH2CH20) Ji or HO (CH Cl 3

CH

2 0) d (CH 2 CH2O), (CH (CHO) CH 2 O) f H 15 wherein a, b, c, di, e and f are integers from 1 to 350 reflecting the respective polyethylene oxide and polypropylene oxide blocks of said polymer. The polyoxyethylene component of the block polymer constitutes at least about 10% of the block polymer. The material 20 preferably has a molecular weight of between about 1,000 and 15,000, more preferably from about 1,500 to about 6-,'000.

These materials are well-known in the art. They are available under the trademark "Pluronic" and *Pluronic a product of BASE Corporation.

Amine oxides having formula: 13R3R~~ wherein R' and R 14 are saturated aliphatic radicals or substituted saturated aliphatic radicals. Preferable amine oxides are those wherein R 1 2 is an alkyl chain of C3802 -21about 10 to about 20 carbon atoms cj R 1 and R' 4 are methyl or ethyl groups or both R12 and R* re alkYl chains of about 6 to about 14 carbon atomns and a methyl Or ethyl group.

Amphoteric synthetic detergents can be broadly described as derivatives of aliphatic tertiary amines, in which the aliphatic radical may be straight chain or branched and wherein one of the aliphatic substituents contain from about 8 to about 18 carbons and one contains an anionic water-so1ubilizing group, carboxy, suipho, suiphato, phosphato or phosphono- Examples of compounds falling within this definition are sodium 3-dodecy[1amino propioflate and sodium 2-dodecylamino propane sul-fonate.

S zwItterioflic synthetic detergents can be broadly described as derivatives of aliphatic quaternary am~monium, phosphonium and suiphoflium compounds in which the aliphatic radical may be straight chained or branched, and wherein one of the aliphatic substituents contains from about 8 to about 18 carbon atoms and one contains an anionic wae-oublzn group, carboxy, suipho, suiphato, phosphato or phosphono. These compounds are frequently referred to as betaines. Besides alkyl betaines, alkyl amino and alkyl ainido betaines are encompassed within this invention.

Alkyl Glycosides

R

5 wherein R 1 5 is a monovalent organic radical a monovalent saturated aliphatic, unsaturated aliphatic or aromatic radical such as alkyl, hydroxyalkyl, alkenyl, hydroxyalkenyl, aryl, alkylaryl, hydroxyalkylarYl, arylalkyl, alkeflYlatyl, arylalkell etc.) containing from C3802 -22 about 6 to about 30 (preferably from about 8 to 18 and more preferably from about 9 to about 13) carbon atoms, R is a divalent hydrocarbon radical containing from 2 to about 4 carbon atoms such as ethylene, propylene or butylene (most preferably the unit (R'6O) represents repeating units of ethylene oxide, propylene oxide and/or random or block combinations thereof); n is a number having an average value of from 0 to about 12; ZI represents a moiety derived from a reducing saccharide containing 5 or 6 carbon atoms (most preferably a glucose unit); and p is a number having an average value of from 0.5 to about 10 preferably from about 0.5 to about Examples of commercially available materials from Henkel Komninditgesellschaft Aktien of Dusseldorf, Germany include

APG

7 300, 325 and 350 with R' 5 being C9-CL,, n is 0 and p is 1.3, 1.6 and 1.8-2.2 respectively;

APG

7 500 and 550 with R is C 12

-C

13 n is 0 and p is 1.3 and 1.8-2.2, respectively; and

APG

7 600 with R" being Cu2-C 14 n is 0 and p is 1.3.

S 20 While esters of glucose are contemplated especially, it is envisaged that corresponding materials based on other reducing sugars, such as galactose and mannose are also suitable.

particularly preferred nonionic surfactants are polyoxyethylene and polyoxypropylene condensates of linear aliphatic alcohols.

The preferred range of surfactant is from 0.5 to 30 by wt., more preferably from 0.5 to 15% by wt of the composition.

038021 -23- Sequet rant~s The compositions herein may also optionally contain one or -more transitiol metal chelating agents. Such chelating agents can be selected from the group consisting of amino carboxylates,-amino phosphonates, polyfuictioflallysubstituted aromatic chelating agents and mixtures therein.

without intending to be bound by theory, it is believed tha('' th e benefit- of these materials is due in part to their exceptional ability to remove iron and manganese ions from -dwashing solutions by formation of soluble chelates- Amino carboxylates useful as optional chelating agents include ethylenediamiffetetraacetates,

N-

hydroxyethylethyieflediaminetriacetates, niAtrilotriacetates, ethylenediamine tetrapropriolateS, triethyleletetraaminehexaacetateS, diethylenetriamiflepentaacetates, ethylenediamile disuccinate, and e-thanoldigly'cines, alkali metal, amm~onium, and substituted ammnonium salts therein and mixtures t herein.

mno phosphonates aeaso suitable for use as chelating agents in the compositions of the invention when at least ~.low levels of total phosphor-us are :permitted in detergent cmoiinand inc~lude ethylenediamnetetrakis raethylenephosmhonates), nitrilotriS (methylenephoSpholates) and diethyleletriamfiflepefltakis (metbhylenephosphoflates).

Pref erably, 'these amino phosphonates do not contain alkyl or al1kenyl groups with -more than about 6 carbon atoms.

Polfuictiolally-sustitied aromatic chelatirig agents are also0 useful in the comnpositions herein. See US-A-3,812,.O 44 Preferred compounds of this type in acid form are 1 7 C3802 24dihydroxydiSUlfobenzenes such as 1, 2-dihydroxy- 3 disul fobenzele.

if utilized, these chelating agents will generallY comprise frm to10% y wight of the detergenlt compositionls herein. More preferably, if utilized, the chelating agents Will comprise from 0.1% to 5.0% by weight of such compositionl.

Enzymes Enzymes capable of facilitating the removal of soils from a I. *,.-substrate maicy also be present in an amount of up to 10% by wt., preferably 1 to 5 wt. Such enzymes include proteases AlcalaSe 7 Savinase 7 and Esperasel from Novo Industries A/S and Purafect OxP7, ex. Genencor), amylases Termamfy1 7 and DurafYl 7 from Novo Industries and Puratect QxAiu7, ex. Genencor).

Process Aids Suitable binding and disintegratinlg agents for ilise in tablets are described in the literature (see! for example, 25 "PharmaceutclDsgFom Volume 1, 1989, Marcel Dekker Inc.-, ISBN 0-8246-804402). Both natural and .synthetic p olymteric materials are suitable. These includeJ *starch such as corn, rice and potato starch and starch Fderivatives sc sUSes10-adU-Sperse-r* provided b National Starch PrimojelT, carboxymethyl starch and sodium g lycolate such as Explotab;7, pre-gelatinlized corn starches such as Nationl'l 1551. and starch 1500; cellulose and cellulose derivatives including carboxymfethyl cellulose such

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C3802 as CourloSe~ t and Nyracel Tm reticulatied sodium carboxyfethyl cellulose, such as Ac-Di-_SOl TM provided by-FMC Corporation, microcystallile cellulose fibres such as Hant1jOCT11 microcrystalline cellulose such as Lattice

T

NT provided by FMC CorporatiOn arnd Avic elTM P- provided by FMC Corporation, methyl cellulose, ethyl cellulose, hydroxyproPYl cellulose and hydroxyprorylmethYl cellulose. Other useful polymers as bjidig/disinltegrating agents are polyvinylpolypyrrolidole products such as Plasdone TM, PVPTM K-30 and PVP K-60 all 10 provided by International Specialty Prodcts; polyviflylpo-lyPyrrolidine products, a crosslinked product of .N-vinyl-2-pyrrolidone such as PolyplasdoleT XL provided by International specialty Products; polymethacrylates, polyvinyl alcohol and polyethylene glycols. Gums such as acacia, tragacalth, guar, locust bean gum and pectin, ****gelatin, sucrose and alginates are also suitable as binding/disintegrating agents. Suitable inorganic materials include magnesium-aluminium silicate such as Veeg~fT

HV

p rovided by R.T. Vanderbilt Co.Inc., bentonite and 1 20 montmorillolite such as Gelwhite TM poie y otenCa Products. Other-suitable binding agents include onoglycerids such as Imwitor TM 191 provided by HulS America *Inc., glyceril Sterates such as Imwitor 7m 900 provided by

TM

Huls America Inc-, and palmoil glycerides such as Imwitor 940 prov ided by Huls America Inc.. The most preferred ~jlj~/iintegrating agents are microcrystalline cellulose and polyethylene glycols. The most preferred polyethylene glycols have a molecular weight of about 2000 to about 15000. Other tablet additives commonly used are lubricant agents for aiding the tablet's processing, such as stearates, waxes,, hydrogenated vegetable oils and polyethylene glycols C3802 -26 and charges such as sugars, sodium sulphate and sodium chloride.

Tablet Form The tablet may be in the form of a layered product. The level of components may vary in each layer. In some instances it may be desirable to have no or low levels of bleaching ingredient with bleach sensitive ingredients such as perfume in one layer and the bleaching ingredient in a separate layer.

it is highly preferable if the tablets of the invention completely dissolve in 6 litres of water(4oFH) at 65 0

C

within 14 minutes. particle Size In the present invention, the total solid material within the tablet is preferably in the range from 0.005 to in order to maximize the dissolution rate and increase the tablet's resistance.

Mixture and Addition Process The addition order of the components of within the formulation can alter the appearance of the tablet.

SIt is preferable if water and any other liquid is added S 30 before the addition of any .tripolyphosphate.

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IF

C3802 i 27 In the context of the present invention a tablet can be defined as any particulate material compacted to form a solid material, the tablet comprising at least one thousand particulates. Preferably the tablet has a diameter of 0.5 cm.

In a typical tablet formulation the addition of components are preferably as follows: 1st filler 2nd surfactant 3rd silicone emulsion 4th perfume buffering system 6th bleaching system 7th builder I particularly preferred are formulations prepared by the Saddition of components in the following order: 20 l st sodium carbonate 2nd non-ionic surfactant S3rd silicone emulsion a 4th- perfume sodium disilicate 6th tetraacetylene diamine

(TAED)

7th sodium perborate 8th sodium tripolyphosphate 9th enzymes Tablet's Pakaging The packaging system of the present invention comprises a body shaped to receive a tablet and a cover(4) which C3802 28 keeps the tablet in the body. Preferably the cover covering the tablet is metallic.

It is particularly advantageous if the packaging system avoids the physical contact of a user with the detergent tablet when placing the tablet in the dish washing machine.

Another important aspect of the present invention is the combined use of the detergent material of the present invention with a packaging of the type here illustrated in figure 1 and 2, as examples.

the invention will now be illustrated by means of the S. following non limiting Examples.

*0 Example: A detergent tablet according to the present invention (Example 1) was prepared as follows.

In a mixer sodium carbonate was added. Under agitation nonionic surfactant, silicone emulsion and perfume were added followed by the remaining powders in the sequence sodium disilicate, tetraacetylene diamine, sodium perborate, sodium tripolyphosphate and finally enzymes. The resulting mixture was left under agitation until homogeneous then transferred to a press and compacted.

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p c^ a. C3802 29 Example 1 formulation Sodium tripolyphosphate 22.63 Sodium disilicate 28.00 Sodium carbonate 24.50 Alcohol ethoxypropoxylate 1.00 0 Sodium perborate 6.00 j Tetracetylene diamine 2.00 Enzyme protease 2.50 Enzyme amylase 2.50 I Silicon emulsion 2.00 perfume/moisture/impurity to 100 A dissolution test was performed in actual use conditions by Splacing a tablet in a plastic basket within a dish-washing machine Enxuta brand Futura model, acquired in 1996. The 20 selected cycle was set to a complete wash and the time taken for the tablet to completely dissolve was measured.

The obtained values are average values of 3 washes for each product.

The table given below demonstrates the tablet according to the invention dissolves completely within 14 minutes, while Sthe comparative examples take longer than 14 minutes to completely dissolve.

Examples A to E are commercially available tablets.

30 Tablet E Invey mAIn fl Tbet C -A;a .Tab3.Ot weight (min) 0 2 4 6 12 14 A Dissolutionl 0 9 18 27 32 36 45 55 64 Tablet B weight 25 23 20 18 16 15 13 10 .8 Dissolutionl 0 30 35 40 Weight Dissolution Weight Dissolution weight Dissolution (%M/Iln) 29 43 57 71 96 100 itioD' TablOt Weigh. Dissolution g) (%m/rn)

Claims (12)

1. A machine dish washing tablet comprising a bleaching system, a silicone and less than 10 wt% of surfactant.

2. A machine dish washing tablet according to claim 1 or claim 2 in which the bleaching system comprises sodium perborate or sodium percarbonate.

3. A machine dish washing tablet according to any preceding claim wherein the silicone is selected from the group consisting of a polymers or copolymers of dimethyl silicone, aminomethoxy functionalised dimethyl silicone and mixtures thereof.

4. A machine dish washing tablet according to any preceding claim in which the particle size of the total solid material within the tablet is in the range 20 from 0.005 to A machine dish washing composition according to any preceding claim in which the silicone is in the form of a silicone emulsion.

6. A machine dish washing tablet according to claim 5 in L: which the level of silicone emulsion added to the product is from 0.5 wt% to 10 wt% of the total product. i: 30 7. A machine dish washing tablet according to claims 5 or S6 in which the level of silicone within the silicone Semulsion is from 2 wt% to 50 wt% of the total weight of the silicone emulsion. 9 S- a C3-3&2 32

8. A machine dish washing tablet according to any one Uf claims 5 6 or 7 in which the silicone is emulsified with a nonionic surfactant.

9. A process for preparing machine dish washing tablets comprising the step of adding a silicone emulsion to a Sformulation that is to be tabletted.

10. A dish washing tablet(1) and a packaging system the packaging system comprising a body shaped to receive a tablet and a cover( 4 which keeps the tablet Sin the body.

11. A dish washing tablet and a packaging system accurdii,:L to claim 1 in which the cover( 3 is metallic.

12. A dish washing tablet packaging system according to S: claim 10 or claim 11 in that the packaging system avoids the physical contact of a user with the detergent tablet when using the tablet.

13. Detergent composition package as illustrated by figures 1 and 2.

14. Use of a packaging system comprising a body shaped to receive a tablet and a cover(4) which keeps the tablet in the body, to store a machine dish washing Stablet. DATED 15\V\\c9 Signed for and on behalf of UNILEVER PLC b er Australia Limited JON y Secreary. Y N I- -V, 2 'Y r