WO2010109164A1

WO2010109164A1 - Method

Info

Publication number: WO2010109164A1
Application number: PCT/GB2010/000483
Authority: WO
Inventors: Antonio Cordellina; Anna Crestana; Juergen Kielholz; Remigio Musci
Original assignee: Reckitt Benckiser N.V.; Reckitt Benckiser (Uk) Limited
Priority date: 2009-03-27
Filing date: 2010-03-17
Publication date: 2010-09-30
Also published as: GB0905332D0

Abstract

A method of ranking detergent performance in a washing operation when comparing the performance of two or more detergent formulations.

Description

METHOD

The invention relates to a method of ranking detergent performance in a washing operation when comparing the performance of two or more detergent formulations.

Methods of analysing detergent performance are known. In these methods normally one or more primary detergent performance (results measured after one wash operation) or secondary detergent performance (results measured after multiple wash operations (usually 5, 10 and 15 wash operations)) parameters is measured and then tabulated in order to give an indication of the performance of the detergent in a certain area .

These performance indicators suffer from a number of disadvantages .

Firstly often multiple scores in a particular performance area are amalgamated / averaged to give an overall performance. This is itself is not an issue but typically the way in which the scores are averaged not only give a misleading result but fails to give a clear idea of the performance difference between different detergent formulations. As an example, in a set of three products, when comparing two formulations a formulation A which obtains a first place in 5 tests and a third place in 4 tests may be ranked overall more highly than a formulation which obtains a second place in 5 test and a first place in 4 of the same tests. This overall ranking gives an improper weighting to some of the tests and gives no sign of the actual ability of the two detergent formulations . Secondly as some of the detergent performance tests are measured instrumentally and each instrument uses its measurement scale it is not always straightforward for a non- specialist, i.e. a person working in the fields of detergents to give a quick / informed judgement call when comparing the performance of two detergent formulations.

It is an object of the present invention to obviate / mitigate the disadvantages outlined above.

According to a first aspect of the invention there is provided a method of ranking detergent performance in a washing operation when comparing the performance of two or more detergent formulations.

The detergent performance measurements may relate to primary detergency, secondary detergency or an admixture of the two measurements

It is understood that primary detergent performance measurements relate to measured properties on stain treatment such as those caused by tea, red wine, chocolate, vegetables, garden soil, blood, sauces, oils on different types of natural or synthetic textiles.

It is understood that secondary detergent performance measurements relate to measured properties such as whiteness degree, soil redeposition, tint value, dye fading etc. In a preferred embodiment of the invention for performing the primary performance analysis the following steps are taken :-

a) Each primary performance cleaning test is performed. b) For each test the performance for each detergent formulation is measured. c) For each test the performance measurements are ranked from the best to the worst performing formulation. d) A grade is assigned for each performance measure. e) An overall score is calculated for each detergent formulation by summing the multiples of the frequency that each grade is attained by the score associated with that grade. f) The overall score for each detergent formulation is ranked in order.

Preferably in step (d) the grade is assigned following a standard statistical method.

Preferably the tests for the primary analysis include those tests indicated above.

When doing the secondary analysis: -

a) Each secondary performance cleaning test is performed. b) For each test the performance for each detergent formulation is measured. c) For each test the performance measurements are ranked from the best to the worst performing formulation. d) A grade is assigned for each performance measure. e) Calculate an overall score for each detergent formulation by summing the grades for each formulation and then normalising the overall scores. f) Ranking the overall score for each detergent formulation in order.

Preferably step (d) is performed by taking the numerical difference between the best score and each other score, dividing that difference by a calibration factor and adding 1. Preferably in step (d) the grade is assigned following a standard statistical method

Preferably the tests for the secondary analysis include those tests indicated above.

For both sets of test the performance measurements may be obtained in accordance with a human perception or instru- mentally .

For both sets of test any data manipulated is preferably performed by a computer using a (statistical analysis) program. Data may be entered and manipulated by the program.

Both sets of tests may be combined to obtain an overall score. Obviously the overall score can be bias towards the primary or secondary measurements to suit.

Usually the tests are performed on a number of different fibre types including, for example, a natural fibre such as cotton and a synthetic fibre such as a polyester. Obviously the overall score (or even the primary / secondary scores) can be bias towards a preferred fibre type. The method according to the invention has been found to be advantageous in that : -

a) It provides an immediate understanding of the outcome of the testing (both to expert formulators and non experts) , thus facilitating their interpretation. b) The calculation tool is flexible since it uses calculation parameters that can be changed by the user.

The method of the invention will now be further illustrated by reference to the following non-limiting Examples.

Examples

Primary Performance Tests

Performance test measurements were taken on 8 detergent formulations for 15 different soils and the results were obtained as below (visual grading after 1 wash at 40⁰C, averages of 5 repetitions) . Scores are from 1-5 with 1 being best .

These scores are then ranked and graded using statistical techniques as follows:

These graded scores are converted into a sum ranking table.

(NB the sum is calculated by the sum of multiple of number hits for each grade) .

These sums are normalised and then added to the normalised sums of other sets of data, if present.

The overall sum is finally normalised. In this way the different detergent formulations are ranked and also an idea given as to the performance delta between the various compositions in numerical terms.

Secondary Performance Tests

Performance test measurements were taken on 8 detergent formulations for 3 different measurements and the results were obtained as below (grading after 15 wash cycles at 40⁰C) . Whitenes s

In these tables the absolute whiteness value is taken.

These values are ordered in decreasing order. In this case the result for formulation D was the best.

The delta value for each composition compared to formulation D is then calculated. This value is divided by the calibration factor (in this case 7) and 1 is added to the value obtained. The number obtained is then graded following an algorithm and added to the set of "Whiteness" performance data at 10 and 15 washes, if present. The overall sum is finally normalised.

This procedure is repeated for each type of textile tested. An overall normalised sum for each formulation for the "Whiteness" performance is thus obtained. Greying

In these tables the absolute greying value is taken.

These values are ordered in decreasing order. In this case the result for formulation B was the best.

The delta value for each composition compared to formulation D is then calculated. This value is divided by the calibration factor (in this case 0.7) and 1 is added to the value obtained. The number obtained is then graded following an algorithm and added to the set of "Greying" performance data at 10 and 15 washes, if present.

The overall sum is finally normalised.

This procedure is repeated for each type of textile tested. An overall normalised sum for each formulation for the "Greying" performance is thus obtained. Analysis

The grades from the whiteness, greying, tint value, dye fading, etc. (tables not shown) are combined and normalised as shown below.

In this way the different detergent formulations are ranked and also an idea given as to the performance delta between the various compositions in numerical terms .

The overall normalised sums from the Primary and Secondary Performance are finally combined for each formulation. In this way the different detergent formulations are ranked and also an idea given as to the overall (Primary and Secondary) performance delta between the various compositions in numerical terms.

Claims

1. A method of ranking detergent performance in a washing operation when comparing the performance of two or more detergent formulations.

2. A method according to claim 1, wherein the detergent performance measurements relate to primary detergency, secondary detergency or an admixture of the two measurements .

3. A method according to claim 1 or 2, wherein the primary detergency properties measured include one or more stains such as those caused by tea, red wine, chocolate, vegetables, garden soil, blood, sauces, oils on different types of natural or synthetic textiles.

4. A method according to claim 1 or 2, wherein the secondary detergent performance measurements relate to measured properties such as whiteness degree, greying, tint value, dye fading etc.

5. A method according to claim 1, 2 or 3, wherein for performing the primary performance analysis the following steps are taken: -

a) Perform each cleaning test b) For each test take measure the performance each detergent formulation. c) For each test rank the performance measure from the best to the worst performing formulation. d) Assign a grade for each performance measure. e) Calculate an overall score for each detergent formulation by summing the multiples of the frequency that each grade is attained by the score associated with that grade. f) Ranking the overall score for each detergent formulation in order.

6. A method according to claim 5, wherein in step (d) the grade is assigned following a standard statistical method.

7. A method according to claim 1, 2 or 4, wherein for performing the secondary performance analysis the following steps are taken: -

a) Each secondary performance cleaning test is performed. b) For each test the performance for each detergent formulation is measured. c) For each the performances measured are ranked in descending order. d) A grade is assigned for each performance measure. e) Calculate an overall score for each detergent formulation by summing the grades for each formulation and then normalising the overall scores. f) Ranking the overall score for each detergent formulation in order.

8. A method according to claim 7, wherein step (d) is performed by taking the numerical difference between the best score and each other score, diving that difference by a calibration factor and adding 1.

9. A method according to claim 7, wherein in step (d) the grade is assigned following a standard statistical method.

10. A method according to any one claim 2 to 9 in which the performance measurements may be obtained in accordance with a human perception or may be taken instrumentally.