WO1983003621A1

WO1983003621A1 - Pourable gel dishwasher compositions

Info

Publication number: WO1983003621A1
Application number: PCT/US1983/000446
Authority: WO
Inventors: Home Products Corporation American; Edwin Ralph Kolodny; Elliot Leibowitz
Original assignee: American Home Prod
Priority date: 1982-04-15
Filing date: 1983-03-28
Publication date: 1983-10-27
Also published as: CA1206391A; NZ203817A; EP0106880A1

Abstract

A pourable dishwashing detergent gel composition comprising an aqueous xanthan gum thickener, a detergency builder, an alkalinity builder or an alkalinity builder mixture, a mixture of anionic and non-ionic surfactants, a chelating agent and water may form of a gel having a Brookfield viscosity from about 3,000 to about 6,000 cps and a yield point from about 250 to about 825. The dishwashing detergent can attain additional agents such as dye, perfume, preservatives, corrosion inhibitors, etc.

Description

POURABLE GEL DISHWASHER COMPOSITIONS

¹ This application relates to new and novel dishwashing detergent compositions. More particularly, the instant invention concerns a pourable dishwashing detergent gel composition comprising: an aqueous xanthan gum

5 thickener, a detergency builder, an alkalinity builder or an alkalinity builder mixture, a mixture of anionic and non-ionic surfactants, a chelating agent and water in the form of a gel having a Brookfield viscosity from about 3,000 to about 6,000 cps and a yield point from about 250 to about 825. The dishwashing detergent can attain additional- agents such as dye, perfume, preservatives,

10 corrosion inhibitors, etc.

In recent years, there has been a strong growth in dishwasher machine ownership. This has resulted in a plethera of dishwasher detergents on the market. These detergents to date have been powders, such as Cascade by Proctor & Gamble, Electrosol by Economics Laboratory, and Dishwasher All by --* Lever Brothers. These dishwasher detergents are specially formulated for use in automatic dishwashers and are more fully described in several of the popular magazines, such as Consumers Research Magazine, August, 1977, pp. 14-17 and Consumers Reports, June, 1980, pp. 371-373. The drawbacks of the conventional dishwasher detergents are well described in U.S. patents 4,260,528 to Fox et al , 20 and 4,226,736 to Bush et al. The first of said patents describes much related art.

The ideal product, according to this patent, despite its high viscosity, must flow easily so it may be dispensed from a tube or plastic squeeze bottle. The product of the patent uses standard, low-foaming surfactants, builders and alkalinity agents to formulate a liquid automatic dishwasher detergent of high viscosity. 25 Thickening action is provided by the addition of Certain types of thickeners, among which are natural and biopolymerie gums and chemical derivatives thereof. Stability and flow are controlled by the addition of critical amounts of urea and polyhydrϊc alcohol with appropriate adjustment of the pH. The urea should be added at a level of about 0.5% to about 8%, and preferably from about 30 2.0 to 5.0% in order to provide adequate stability without objectionable odor. The products of this patent also have from about 0.3 to about 10% of a polyhydric ^* alcohol selected from thegroup consisting of glycerol, ethylene glycol, propylene glycol and mixtures thereof. The products still further have a Brookfield viscosity from about 13,000 cps to about 150,000 cps. Patent No. 4,226,736 discloses a low-foaming machine dishwasher detergent composition comprising an aqueous thickener, non-ionic surfactant and water in the form of a gel having a minimum yield point of at least 1170 so that it will not leak out of a sealed or closed cup, prior to its automatic opening for dispensing the detergent for a second or subsequent wash cycle. This patent discloses multitudeness thickening agents including xanthan gum, although such material is not disclosed in any of the specific examples. The products have a minimum yield point of at least about 1170 and a Brookfield viscosity of about 472,000 cps. We have found certain pourable gel dishwashing detergents having a relatively low viscosity and a relatively low yield point whereby the gel formulation can be conveniently filled into bottles at the point of manufacture, easily and conveniently poured into dispensing cups of a dishwasher machine by the user. The gel formulation sets up sufficiently in the dishwasher cups so that little or no leakage occurs from a sealed or closed cup, prior to its automatic opening for., dispensing the detergent for a second or subsequent wash cycle, as seen by a satisfactory cleansing of the dishes and silverware in the automatic dishwasher, even though the gel formulation is placed into the sealed cup only.

In further detail, our invention relates to a dishwasher gel formulation which is stable, with a high pH and retains its viscosity. The gel is completely soluble in hot water and completely rinses out from a dishwasher cup without gritty deposits or powder detergent residues. It is pseudoplastic in nature so that it may pour freely and completely from a bottle^ yet set up and resist draining from the machine dishwasher cup. It creates minimal foam even with proteinaceous soils, reduces the deposition of hard water scale that causes spots and haze, removes tough dried-on soils and is safe for fine china and silver. It is not corrosive to the maehine and the contents. Thus, the dishwasher gel detergent composition of the present invention comprises:

(a) from about 0.5 to about L5% of an aqueous xanthan gum thickener;

(b) from about 8 to about 15% of a detergency builder; (c) from about 3 to about 7% of an alkalinity builder or an alkalinity builder mixture;

(d) from about 2 to about 5.5% of a mixture of anionic and low foaming, non-ionic surfactants;

5 (e) from about 2 to about 9% of chelating agent; and

(f) water, said composition having a pH of 11-13 and being in the form of a gel characterized as having a Brookfield viscosity from about 3,000 to about 7,000 cps and a yield point from about 10 250 to about 825.

More preferably, the dishwasher detergent gel composition of the present invention comprises:

(a) from about 0.8 to about L2% of an aqueous xanthan gum thickener;

15

(b) from about 9 to about 14% of a detergency builder; (e) from about 2 to about 4% of a first alkalinity builder and about 1 to about 3% of a second alkalinity builder;

(d) from about 0.3 to about 1.2% of an anionic surfactant and from about 1.7 to about 4.3% of a non-ionic surfactant;

20

(e) from about 3 to about 5% of a first chelating agent and about 1 to about 4% of a second chelating agent; and

(f) water. Test methods:

(A) Viscosity: All viscosities of products were measured on a ^*-" Brookfield Model RVT Synchro-Leetric Viscometer using appropriate speeds and spindles as suggested by the manufacturer. With very gelatinuous materials, with which there is a tendency for the spindle to "bore" a hole in the sample and thus give erroneous readings, a Brookfield Model LVT Viscometer was supported on a Brookfield Helipath Stand (Model C) and the corresponding spindles were ³⁰ used. The Helipath stand slowly lowers the viscometer spindle deeper into the sample so the spindle continuously encounters fresh sample. All viscosities are read at 25° C. just prior to testing the sample for cup retention.

OMFI (B) Yield Value: Our values are determined in a manner as in U.S. Patent 4,266,736. The viscosities are determined, as described above, at 0.3 and 0.6 rpm spindle speeds. At these speeds very little shear is placed on the sample. The values are then applied in the formula: Yield Value _ (apparent Viscosity at 0.3 rpm) - (apparent Viscosity at

0.6 rpm)

100 where the viscosities are given in centipoises.

(C) Evaluation: Performance testing on the compositions is done in the following manner, which is a variation of that prescribed by the American Society for Testing and Materials in the "Method for Measurement of Depositions on Glassware During Mechanical Dishwashing" (D 3556-76T).

Ten dinner plates were uniformly soiled. Two of each plates had (a) a mixture of margarine and powdered milk, (b) spinach, (c) eggs, ( ) cereal and (e) mustard. Seven grams of each of the above soils was placed uniformly in the center area of each of two dinner plates. One gram of the above standard soils was placed on one each knife, fork and spoon. Two grams of milk was placed into each of eight glasses. The soiled items, along with four unsoiled glasses, were placed in a Kitchen Aid Energy Saver IV Superba dishwasher by Hobart. The water supply was adjusted to 140° F. and 150 ppm hardness. When using the el compositions of the present invention, fifty-two grams of detergent, which is approximately three tablespoons, was placed into the second cup; no detergent was placed in the first cup. With the control, forty-one grams of detergent was placed in each cup.

After washing, each soiled dish and each eating utensil was evaluated by a panel of ten. Each panelist counted the number of particles of soil ^• remaining up to a maximum of ten. Articles with more than ten particles of soil were rated 10+. Any particle of 10 mm. or larger in any direction was rated 10+.

Each soiled and unsoiled glass and each article of silver was examined for spotting and filming; each piece of silver was examined for cleaning and spotting. The spotting evaluation was by a panel of ten according to the following criteria: no spots, 1; spots at random, 2; about 1/4 of surface covered, 3; about 1/2 of surface covered, 4; and virtually complete coverage, 5. The filming evaluation was by a panel of ten according to the followin criteria: none, 1; barely perceptible, 2; slight, 3; moderate, 4; and heavy, 5. The tests were completed five times with the position of the various soiled articles altered each time. The values for each material was averaged together to provide an overall rating.

The following examples will serve to further illustrate the present invention. All percentages herein are by weight. In Examples 1-4, liquid gel dishwasher detergent formulations were made up with the following compositions:

DISHWASHER GEL FORMULATIONS

Ingredient Function Example

1 2 3 4

Xanthan gum Thickener 1.0 1.0 1.1 1.1

Tetrapotassium Detergent 13.0 13.0 10.0 10.0 pyrophosphate Builder .

NaEDTA (38%) Chelating 10.0 10.0 13.0 13.0 Agent

Na metasilicate Alkalinity 3.0 3.0 3.0 3.0 pentahydrate Builder

Na₂CO Alkalinity 2.0 2.0 2.0 2.0 Builder

Gluconic Acid (50%) Chelating 3.0 3.0 7.0 6.0 Agent

Gafac RE-610 Anionic 1.0 1.0 1.0 0.5 Surfactant

Tetronic 150-R1 Non-ionic 2.0 2.0 2.0 — Surfactant

Triton CF-87 Non-ionic - - 1.0 - Surfactant Ingredient Function Example Triton CF-32 Non-ionic - - - 4.0 Surfactant

Sodium sulfite Preservative - 0.2 0.2 0.1

Dye - 0.055 0.0275 0.0275

Perfume - 0.1 0.08 0.08

Water 65.0 65.6 59.6 60.2

Viscosity cps 5000 5600 5000 5400 pH 12.5 12 11.3 11.7

Yield Value 270 271.5 815 535

Examples and the formulations of Examples 2-4 were tested as to their cleaning capacity, filming and spotting. Formulation 1 is the same as formulation 2 without the preservative, dye and perfume. The results were shown hereinbelow according to the following table using commercially available Cascade, containing 8.7% phosphorus as phosphates, as a control:

EXAMPLE 5

TABLE

Product Cleaning Spotting Filming of Example Dishes Tableware Glasses Glasses

2 0.49 0.44 2.7 1.7

3 0.17 0.17 2.9 1.6

4 0.07 0.17 2.4 2.6

Control 0.2 0.17 1.7 2.1

The products of the present invention average less than about 2.4% phosphorus in the the form of phosphates, or less than about L3 grams for a 3 tablespoon level use (52 grams). Cascade, containing 8.7% phosphorus, on the other hand, provides 7.14 grams, when 41 grams is used in each cup. As can be seen from the above, although the products of the present invention are comparable in cleaning, spotting and filming to Cascade, the phosphate level is only about one-fifth that of the phosphate level in Cascade.

The particular dye and perfume used herein is not critical, provided said dye and/or perfume is stable at the pH of the dishwasher gel composition and 5 does not react with any of the other ingredients in the dishwasher composition. It may be desirable to use sodium sulfite as a preservative for some of the ingredients herein. This is also, however, not critical to the functioning of the present invention, but merely is to increase the shelf life thereof.

Xanthan gum is available under the tradename Xanthan Gum K9C57 10 from Kelco, a division of Merck & Co. The Gafac RE-610 anionic surfactant is an organic phosphate ester free acid complex available from GAF Corporation. The Tetronic 150-R1 non-ionic surfactant is a polyoxyethylene-polyoxypropylene ethylenediamine condensate available from BASF Wyandotte Corporation. Triton CF-32 is a non-ionic, low-foam surfactant, an amine polyglycol 15 condensate available from Rohm & Haas Co. Triton CF-87 is an alkyl aryl ether- modified terminated 90% non-ionic surfactant available from Rohm & Haas Co. Illustratory specific dyes useful herein are: Acid Blue 239, available under the name Erionyl Brilliant Blue 7GS from Ciba-Geigy; Acid Yellow 40S, available under the name Polar Yellow 5GL from Ciba-Geigy, while an illustratory 20 perfume is Alpine 101-911, available from Alpine Aromatics Intl.

Although preferred ingredients are disclosed and claimed, the obvious equivalents are included within said claims. For example, part of the xanthan gum can be replaced by other thickeners such as locust bean gum, tragacanth and/or sodium alginate, provided, however, the viscosity and the yield point 5 remains within the limits herein. Part of the tetrapotassium pyrophosphate can , be replaced by other pyrophosphates, such as sodium tripyrophosphate;

• ethylenediamine tetraaeetic acid and gluconic acid can be replaced in part or totally by a water soluble salt thereof or such salt may be formed in situ in the manufacture of the formulation. Other suitable chelating agents are 0 nitrilotriacetic acid or citric acid and the water soluble salts of either, such as the sodium or potassium salt. The NaCOβ alkalinity builder can be substituted by equivalent alkalinity builders such as K2CO3 or NaOH, etc. Although sodium metasilicates are preferred, other water soluble silicates such as alkali metal, eg., sodium or potassium, silicates, with varying M2O/SiO2 ratios (alkali metal salt oxide to silicon dioxide) are suitable.

Claims

CLAIMS:

L A pourable dishwasher detergent gel composition, comprising:

(a) from about 0.5 to about 1.5% of an aqueous xanthan gum thickener;

(b) from about 8 to about 15% of a detergency builder (c) from about 3 to about 7% of an alkalinity builder or an alkalinity builder mixture; (d) from about 2 to about 5.5% of a mixture of anionic and low foaming, non-ionic surfactants; (e) from about 2 to about 9% of chelating agent; and

(f) water, said composition having a pH of 11-13 and being in the form of a gel characterized as having a Brookfield viscosity from about 3,000 to about 7,000 cps and a yield point from about 250 to about 825.

2. The dishwasher detergent gel composition of claim 1, comprising:

(a) from about 0.8 to about 1.2% of an aqueous xanthan gum thickener;

(b) from about 9 to about 14% of a detergency builder; (c) from about 2 to about 4% of a first alkalinity builder and about 1 to about 3% of a second alkalinity builder

(f) water.

3. The composition of claim 2 additionally containing a dye and perfume.

4. The composition of claim 3 additionally containing a preservative.

O _: ^.^ 5. The composition of claim 3, comprising:

(a) about 1% xanthan gum;

(b) about 13% tetrapotassium pyrophosphate;

(c) about 3% sodium metasilicate and about 2% sodium carbonate; (d) about 1% anionic surfactant and about 2% non-ionic surfactant;

(e) about 3.8% ethylenediamine tetraacetic acid and about 1.

5% gluconic acid; and

(f) the balance comprising water, dye and perfume.

6. The composition of claim 3, comprising:

(a) about 1.1% xanthan gum;

(b) about 10% tetrapotassium pyrophosphate;

(c) about 3% sodium metasilicate and about 2% sodium carbonate;

(d) about 1% anionic surfactant and about 2% non-ionic surfactant;

(e) about 5% ethylenediamine tetraacetic acid and about 3.5% gluconic acid; and

(f) the balance comprising water, dye and perfume.

7. The composition of claim 3, comprising: (a) about 1.1% xanthan gum;

(b) about 10% tetrapotassium pyrophosphate;

(c) about 3% sodium metasilicate and about 2% sodium carbonate;

(d) about 0.5% anionic surfactant and about 4% non-ionic surfactant; (e) about 5% ethylenediamine tetraacetic acid and about 3% gluconic acid; and (f) the balance comprising water, dye and perfume.

8. A method for cleaning food-soiled dishware and cutlery in an automatic dishwasher machine while reducing the loss of a detergent composition due to leakage from the dispenser cup prior to its utilization during the washing step of the machine, which comprises adding to the dishwasher dispenser cup prior to the operation of the dishwasher, the detergent composition claimed in claim L

9. The method of claim 8, wherein said composition comprises that of claim 5.

10. The method of claim 8, wherein said composition comprises that of claim 6. IL The method of claim 8, wherein said composition comprises that of claim 7.