WO2005066324A1

WO2005066324A1 - Anti-incrustation agent

Info

Publication number: WO2005066324A1
Application number: PCT/GB2005/000017
Authority: WO
Inventors: Arnaud Van Berleere; Christopher Raymond Jones
Original assignee: Rhodia Uk Limited
Priority date: 2004-01-08
Filing date: 2005-01-07
Publication date: 2005-07-21
Also published as: GB0400310D0

Abstract

The present invention relates to an anti-incrustation agent comprising an alkanolamine phosphonate of formula: (I) and/or (II) where R is chosen from -H, -CH3, -C2H5, -OHCH2 or R1, R1 is chosen from -OHCH2 or [(CR2)nNCR2PO3H2]mCR2PO3H2 where m is 0 to 10 and n is 2 or 3. Also disclosed is a composition or formulated laundry detergent including the above anti-incrustation agent and a method of lowering the incrustation of a garment during a laundry cycle by use of the anti-incrustation agent above.

Description

ANTI-INCRUSTATION AGENT

The present invention relates to an agent for use in the reduction of incrustation on garments and, in particular, to the use of such an agent and a method of using such an agent.

In laundry applications and in particular where phosphate free detergent formulations are used, formation of mineral incrustation on garments occurs. This incrustation is essentially made up of calcium carbonate and, to a lesser degree, calcium silicate and calcium zeolate. These deposits on garments generate an unpleasant appearance and are detrimental to the 'soft feel' of the garment.

It is an object of the present invention to provide an agent to reduce mineral incrustation on garments.

Accordingly, the present invention in a first aspect, provides an anti-incrustation agent comprising an alkanolamine phosphonate of formula (1) :

II Where R may be -H, -CH₃, -C₂H₅, -OHCH₂ or R\ R¹ may be -OHCH₂ or [(CR₂)_nNCR₂PO₃H₂]_mCR₂PO₃H₂ where m is 0 to 10 and n is 2 or 3.

The preferred anti-incrustation agent is of formula 1 and is (2 - hydroxy ethyl) iminobis (methylene phosphonic acid) . This agent is available under the trade name Briquest® 221-50A.

The agent of the present invention may be formulated with one or more of other scale inhibitors, chelating agents, builders, corrosion inhibitors, enzymes, optical brighteners, surfactants, fragrances, oxidising agents, preferably active oxygen agents such as perborate, active oxygen compound activators such as tetraacetylethylenediamine (hereinafter TAED) , dispersants and zeolites.

The anti-incrustation agent may be provided in solid or liquid form.

According to a second aspect, the present invention provides a composition of an anti-incrustation agent according to the first aspect of the invention with one or more of other scale inhibitors, chelating agents, builders, corrosion inhibitors, enzymes, optical brighteners, surfactants, fragrances, oxidising agents, preferably active oxygen agents such as perborate, active oxygen compound activators such as TAED, dispersants and zeolites.

The composition may be provided in solid or liquid form.

According to a third aspect the present invention provides a formulated laundry detergent including an anti-incrustation agent according to the first aspect of the present invention. The anti-incrustation agent may be provided in an amount of between 0.01 and 20% by weight based on the weight of the detergent, preferably between 0.1 and 10% by weight.

The formulated laundry detergent may be provided in solid or liquid form.

The formulated laundry detergent may include one or more of other scale inhibitors, chelating agents, builders, corrosion inhibitors, enzymes, optical brighteners, surfactants, fragrances, oxidising agents, preferably active oxygen agents such as perborate, active oxygen compound activators such as TAED, dispersants and zeolites.

According to a fourth aspect, the present invention provides the use of an anti-incrustation agent in accordance with the first aspect of the present invention, a composition in accordance with the second aspect of the present invention or a formulated laundry detergent in accordance with the third aspect of the present invention in laundry applications to reduce the amount of incrustation on garments.

Incrustation is defined as the residue present on garments after a laundry wash cycle. Incrustation typically comprises the build up calcium carbonate, calcium silicate or calcium zeolate or a combination thereof.

The use of the anti-incrustation agent provides garments with less then 1% incrustation (m ash/m fabric). Preferably, the use of the agent provides garments with less than 0.5% incrustation.

The agent is preferably used at a temperature of between 20 and 90° C. More preferably, the agent is used at a temperature of between 30 and 70°C, most preferably between 40 and 70° C. When we say garments we mean any fabric materials including natural fabric materials such as cotton, wool and silk and synthetic fabric materials such as polyester, viscose and the like, we also mean any article made from these materials.

According to a fifth aspect, the present invention provides a method of lowering the incrustation of a garment during a laundry wash cycle, which method comprises adding an anti-incrustation agent in accordance with the first aspect of the invention to the wash cycle.

The agent may be added in the form of a solid or a liquid. The agent may be added before or during a wash cycle.

According to a sixth aspect, the present invention provides a method of lowering the incrustation of a garment during a laundry wash cycle, which method comprises adding a composition in accordance with the second aspect of the invention to the wash cycle.

The composition may be added in the form of a solid or a liquid. The composition may be added before or during a wash cycle.

According to a seventh aspect, the present invention provides a method of lowering the incrustation of a garment during a laundry wash cycle, which method comprises adding a formulated laundry detergent in accordance with the third aspect of the invention to the wash cycle.

The formulated laundry detergent may be added in the form of a solid or a liquid. The formulated laundry detergent may be added before or during a wash cycle. The invention will now be described merely by way of example, with reference to the following;

In laundry, more specifically in phosphate-free formulations, wash after wash, formation of mineral incrustation on cotton appears (essentially made up of calcium carbonate and, to a lesser degree, calcium silicate and calcium zeolate. These deposits on fabrics generate an unpleasant appearance and are detrimental to the soft feel of cotton.

To avoid this phenomenon, it is necessary to introduce a good anti-incrustation agent into the formulation.

Two basic tests were used to evaluate the performance of alkanolamine phosphonates in detergent applications, namely a calcium complexation test and an anti-incrustation test.

1. CALCIUM COMPLEXATION/CALCIUM PHOSPHATE

INHIBITION TEST

The aim of this test is to determine the ability of alkanolamine phosphonates to sequestrate calcium and prevent the deposition of calcium phosphate. For that purpose, an insoluble calcium salt is built in water under certain conditions and the minimum concentration of phosphonate required to avoid precipitation is determined.

In this respect, Briquest 221-50A, an agent in accordance with the present invention, was compared to a conventional phosphonate currently used in the industry and known as Briquest ADPA-60A. • Protocol:

This protocol is based on the measurement of turbidity (% of transmission) of a solution containing calcium (Ca²⁺) and an anion (PO₄ ³) , knowing that the mixture of the two ions generates an insoluble precipitate in water, after a given time.

In this case, transmission is a good way to follow the precipitation: a clear solution indicates no precipitation while cloudiness indicates presence of precipitate ( in the latter, transmission drops below 100% ) .

• Conditions:

Water:

- Contrex water diluted two times (with deionised water)

- Volume used: 100 ml

Additive to water:

- Addition of various amounts of phosphonates to diluted Contrex water

Orthophosphate solution additive: - Solution of sodium orthophosphate (pH = 7) at 5 g/1 in pure water. - Volume used: 100 ml

Mixing of water and additives gives a total volume of 200 ml.

Measurement of turbidity was carried out using a turbidimeter with mirror cell at 650 nm after leaving the mixture for 10 minutes under moderate stirring (50 rpm) at a temperature of 30 °C (regulated using an appropriate bath aid) . It means that the mixture has a total volume of 200ml and contains the following at the specified concentrations:

Ca: 1200ppm

Mg: 21 ppm

Na: 2.5 ppm

K: 1 ppm

Sulphate: 300 ppm

Hydrogenocarbonate : 100 ppm

Chloride: 2.5 ppm

Nitrate: 0.7 ppm

Na₂HPO₄: 2500 ppm

Final hardness: 39°TH The graph below demonstrates the superior performance of 221-50A, as a calcium complexation agent and calcium phosphate inhibitor, especially at low dosage levels (10-40ppm), which is critical for cost effective treatments .

Power complexation(Ca-phosphate) at 30°c

0 10 20 30 40 50 60 70 80 90 100 ppm active chelant 2. ANTI-INCRUSTATION TEST

Formulations used:

Zeolithe 4 A: 25%

Sokalan CP5: 5%

Nabion 15: 8%

LABS: 6% Symperonic A7: 12%

Perborate mono: 15%

TAED: 5%

Savinase: 0.5%

CMC: 1.5% Sodium sulfate: to 100%

Phosphonates: Added at 0.0, 0.3, 0.6 & 0.9% w/w(expressed as active material)

Mineral incrustation on cotton is essentially made up of calcium carbonate and, to a lesser degree, calcium silicate and calcium zeolate. To determine the rate of incrustation of a detergent, cotton fabrics are washed six times successively in the terg-o-tometer with the detergent being tested. The cotton swatches are then calcined, and the calcium oxide ash represents the rate of incrustation of the formulations under assessment.

The following are used:

Terg-o-tometer: a scaled-down model of American washing machines, made up of 4 or 6 stainless steel beakers on which pulsating agitators with variable agitation speed are adapted. The beakers are placed in a thermostatically controlled well.

Fabrics: To determine the incrustation rate of a detergent it is necessary to use: - 5 swatches (10 x 13 cm) of TERY 12A terrycloth

commercial reference: TERY 12A cotton-polyamide (92%/8%) special incrustation cloth supplier: TESTFABRICS - USA

- 5 swatches (10 x 12 cm) of CNI cotton

commercial reference :_CNI cotton swatches (10 x 12 cm) supplier: Center for Testmaterials (CFT) Netherlands

The finish of the TERY 12 A is removed before use in the test. This step is to eliminate the finish without laying down a calcium carbonate incrustation on the fibers.

The piece of TERY 12A is dried in a clothes dryer at the setting for cotton and then cut up into 10 xl2cm swatches. Five TERY 12A swatches are divided into bunches of 200 and enclosed in towels sewn up to form completely closed sacks. They are subjected to the same finish-removing process as the TERY 12A but are dried with a roller dryer.

Mettler AE 200 precision balance (10⁴ g): To weigh ash from the calcined swatches AEG LAVAMAT 2050 TURBO washing machine: Used on the long 40 °C cycle with pre wash to remove the finish from the TERY 12A and the CN1 cotton

AEG LANATHERM 550 clothes dryer: Used on setting n°l for cotton

HERMANN MORITZ MF4 oven: Used at 950 °C

Silica crucible: Used at 950 °C

• Protocol

The protocol to assess incrustation rates comprises the following two main phases: A: Washing the samples B: Measuring the incrustation rate

A: Sample washing

To determine a detergent's incrustation rate it is necessary to prepare five swatches of TERY 12A and five swatches of CN1 cotton and evaluate them under the following conditions:

- Water: 39° French TH

(dilute Contrexeville mineral water-quantity to be prepared : 12 1) -Terg-o-tometer temperature: 60° ± 2°C

-Number of washings: 6

-Wash speed: 20 + 1 min

-Agitation speed: 100 ± 3 cycles/min

-Formula concentration: 5 ± 0.01 g/1 -Three hand rinsings between each washing: the first time with water at

39° French TH and the following two times with tap water. Preparation of water at 39° French TH: Starting with Contrexeville natural mineral water, whose hardness is 156° French TH (of appendix 1 on how to measure water hardness, dilute 250 ml of this mineral water with 750 ml of deionized water to get one liter of water at 39 "French TH.

The swatches are placed one after the other in a clean beaker of the terg- o-tometer, and detergent is added over them. One liter of water at 39° TH is poured in, and the beakers are agitated for 20 minutes.

After washing, the wash water is poured down the sink, and the swatches are wrung out by hand. Another liter of water at 39° TH is poured over the swatches to complete the first hand rinse. The two subsequent rinses are carried out like the first one, except that tap water is used instead of water softened to 39° French TH.

The swatches are separated from each other before being placed once again in a terg-o-tometer beaker and subjected to the next wash phase.

After the last of the six washings and three rinsings, the swatches are placed in a weighing crucible (uncovered) to be oven-dried for three hours at 110°C (Two washed swatches of TERY 12a and two washed swatches of CN1 cotton are thus left over to be used uncalcined.)

B: Measurement of Incrustation Rate

The oven is heated at least five hours before calcining the swatches. The following operations are to be carried out to determine a detergent^'s incrustation rate:

- Remove the weighing receptacles (closed) from the drying oven and place them in a desicator until they have cooled down to constant mass temperature. - Place the silica crucibles in a 950 °C oven for 20 minutes, and then transfer them to a desicator equipped with heat protection, being careful not to let them touch the walls. Let them cool and ascertain the tare to obtain mass Cl.

- Place the three swatches of TERY 12A or cotton CN1 in a previously tared crucible to get mass M.

- Burn the three swatches placed in the silica crucible in the flame of Bunsen burner.

- Use a pair of pliers to place the crucibles in the oven set at 950°C for three hours. They are then transferred to a heat-protected desicator to cool down.

- Weigh the crucibles containing the ash to get mass C2.

• Results

The percentage of incrustation of a detergent is expressed as the ratio of the ash mass over the swatch mass:

Incrustation rate= [(C2 - C1)/(M - Cl)] x 100

To determine the incrustation rate of each formulation, cotton fabrics are washed six times successively in a terg-o-tometer with the powder blended or not with the tested phosphonates. The cotton swatches are then calcined, and the weighed amount of calcium oxide ash represents the incrustation rate of the formulations under assessment. Conditions are: - cotton fabric: 4 pieces of TERY 12A - temperature: 60°c - washing time: 20 minutes - water hardness: 39°TH - dosage of powder detergent: 5g/l

The incrustation level is equal to the % of residue (m ash/m fabric) after 3 hours at 950 °c

The rate of incrustation of a formulation is evaluated as follows:

- low incrustation: < 1% - average incrustation: > 1% < 3% - high incrustation: > 3%

The comparative results for 221-50A and ADPA-60A are highlighted in the table below (dose level expressed as active ingredient) :

These results clearly show that alkanolamine phosphonates, such as Briquest 221-50 A are highly effective anti-incrustation agents for laundry detergent applications and are far more effective than conventional products such as ADPA-60A.

Claims

1. An anti-incrustation agent comprising an alkanolamine phosphonate of formula

I II

where R is chosen from -H, -CH₃, -C₂H₅, -OHCH₂ or R¹, R¹ is chosen from -OHCH₂ or [(CR₂)_nNCR₂PO₃H₂]_mCR₂PO₃H₂.where m is 0 to 10 and n is 2 or 3.

2. The anti -incrustation agent according to Claim 1 wherein the agent is (2 - hydroxy ethyl) iminobis (methylene phosphonic acid) .

3. The anti-incrustation agent according to Claim 1 or Claim 2 wherein the agent is provided in solid or liquid form.

4. The anti-incrustation agent according to any preceding claim wherein the agent is formulated with one or more of other scale inhibitors, chelating agents, builders, corrosion inhibitors, enzymes, optical brighteners, surfactants, fragrances, oxidising agents, active oxygen compound activators, dispersants and zeolites.

5. The anti-incrustation agent according to Claim 4 wherein the oxidising agent is an active oxygen agent.

6. The anti-incrustation agent according to Claim 4 or Claim 5 wherein an active oxygen compound activator is tetraacetylethylenediamine.

7. A composition comprising an anti-incrustation agent according to any of claims 1 to 6 and one or more of:- other scale inhibitors, chelating agents, builders, corrosion inhibitors, enzymes, optical brighteners, surfactants, fragrances, oxidising agents, active oxygen compound activators, dispersants and zeolites.

8. The composition according to Claim 7 wherein the oxidising agent is an active oxygen agent.

9. The composition according to Claim 7 or Claim 8 wherein an active oxygen compound activator is tetraacetylethylenediamine.

10. The composition according to any of Claims 7 to 9 wherein the composition is provided in solid or liquid form.

11. A formulated laundry detergent including an anti-incrustation agent according to any of Claims 1 to 6.

12. The formulated laundry detergent according to Claim 11 wherein the anti-incrustation agent is provided in an amount of between 0.01 and 20% by weight based on the weight of the detergent.

13. The formulated laundry detergent according to Claim 11 or Claim 12 wherein the anti-incrustation agent is provided in an amount of between 0.1 and 10% by weight based on the weight of the detergent.

14. The formulated laundry detergent according to any one of Claims 11 to 13 wherein the formulated laundry detergent includes one or more of:- other scale inhibitors, chelating agents, builders, corrosion inhibitors, enzymes, optical brighteners, surfactants, fragrances, oxidising agents, active oxygen compound activators, dispersants. and zeolites.

15. The formulated laundry detergent according to Claim 14 wherein the oxidising agent is an active oxygen agent.

16. The formulated laundry detergent according to Claim 14 or Claim 15 wherein the active oxygen compound activator is tetraacetylethylenediamine .

17. The formulated laundry detergent according to any of Claims 11 to 16 wherein the formulated laundry detergent is provided in solid or liquid form.

18. Use of an anti-incrustation agent in accordance with any of Claims 1 to 6, a composition in accordance with any of Claims 7 to 10 or a formulated laundry detergent in accordance with Claims 11 to 15 in laundry applications to reduce the amount of incrustation on garments.

19. The use according to Claim 18 wherein the use provides garments with less then 1% incrustation (m ash/m fabric).

20. The use according to Claim 18 wherein the use provides garments with less then 0.5% incrustation (m ash/m fabric).

21. The use according to any of Claims 18 to 20 wherein the use takes place at a temperature of between 20 and 90°C.

22. The use according to any of Claims 18 to 21 wherein the use takes place at a temperature of between 30 and 70°C.

23. The use according to any of Claims 18 to 22 wherein the use takes place at a temperature of between 40 and 70 °C.

24. A method of lowering the incrustation of a garment during a laundry wash cycle, which method comprises adding an anti-incrustation agent in accordance with any of Claims 1 to 6 to the wash cycle.

25. The method according to Claim 24 wherein the agent is added in the form of a solid or a liquid.

26. The method according to Claim 24 or Claim 25 wherein the agent is added before or during a wash cycle.

27. A method of lowering the incrustation of a garment during a laundry wash cycle, which method comprises adding a composition in accordance with any of Claims 7 to 10 to the wash cycle.

28. The method according to Claim 27 wherein the composition is added in the form of a solid or a liquid.

29. The method according to Claim 27 or Claim 28 wherein the composition is added before or during a wash cycle.

30. A method of lowering the incrustation of a garment during a laundry wash cycle, which method comprises adding a formulated laundry detergent in accordance with any of Claims 11 to 15 to the wash cycle.

31. The method according to Claim 30 wherein the formulated laundry detergent is added in the form of a solid or a liquid.

32. The method according to Claim 30 or Claim 31 wherein the formulated liquid detergent is added before or during a wash cycle.

33. An anti-incrustation agent substantially as described herein and with reference to the Examples.

34. A composition, including an anti-incrustation agent, substantially as described herein and with reference to the Examples.

35. A formulated laundry detergent, including an anti-incrustation agent, substantially. as described herein and with reference to the Examples.

36. Use of an anti-incrustation agent in accordance with any of Claims 1 to 6 and 33, a composition in accordance with any of Claims 7 to 10 and 34 or a formulated laundry detergent in accordance with Claims 11 to 15 and 35 in laundry applications to reduce the amount of incrustation on garments substantially as described herein and with reference to the Examples.

37. A method of lowering the incrustation of a garment during a laundry wash cycle substantially as described herein and with reference to the Examples.