AU600263B2

AU600263B2 - Stable liquid diperoxyacid bleach

Info

Publication number: AU600263B2
Application number: AU70761/87A
Authority: AU
Inventors: Stanton Lane Boyer; Thomas Edward Cook; James Michael Van Der Meer
Original assignee: Procter and Gamble Co
Current assignee: Procter and Gamble Co
Priority date: 1986-03-31
Filing date: 1987-03-30
Publication date: 1990-08-09
Anticipated expiration: 2007-03-30
Also published as: KR940006254B1; EP0240481A1; GB2188654A; CA1294510C; KR870009073A; HK104692A; IE60011B1; EP0240481B1; DE3763424D1; SG99892G; JPS63399A; GR3000789T3; JP2528867B2; AU7076187A; GB8707571D0; MX172458B; IE870814L

Description

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1' 600263

AUSTRALIA

Patents Act COMPLETE SPECIFICATION

(ORIGINAL)

Application Number: Lodged: Complete Specification

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Pul 7e -7 Class Int. Class Lodged: ccepted: blished: tainz 1-1 PTiority 11 ii j 41 cc

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0 0 00 a o <c Ccog C C 0O QI c C o c 0 c 0t C C t 0 C 00 o oc *0 c 0 0 APPLICANT'S REFERENCE: P&G Case 3512R Name's) of Applicant(s): The Procter Gamble Company Address(es) of Applicant(s): One Procter Gamble Plaza, Cincinnati, Ohio 45202, UNITED STATES OF AMERICA.

Address for Service is: PHILLIPS ORMONDE and FITZPATRICK Patent and Trade Mark Attorneys 367 Collins Street Melbourne 3000 AUSTRALIA Complete Specification for the invention entitled: STABLE LIQUID DIPEROXYACID BLEACH Our Ref 50117 POPF Code: 44135/44135 The following statement is a full description of this invention, including the best method of performing it known to applicant(s): Related Art: 6003q/l1 1 -1A- STABLE LIQUID DIPEROXYACID BLEACH Stanton L. Boyer Thomas E. Cook James M. VanderMeer Technical Field The present invention relates to stable liquid diperoxyacid bleach compositions useful for bleaching Sfabrics, hard surfaces and other substrates. The compositions contain water-insoluble aliphatic diperoxyacid particles, C 11

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13 linear alkylbenzene sulfonate surfactant, cumene sulfonate as an optional ingredient, magnea a. Vsium sulfate, sodium or potassium sulfate as an optional 15 ingredient, and water. The compositions also have a pH of from about 2 to about 4.5 and a viscosity of from about 50 to about 1000 cps at 20 0 C. The ingredients are R combined at certain carefully balanced levels and ratios, as hereinafter described, to provide compositions 20 exhibiting good physical and chemical stability.

Background Art 0 00 European Patent Application 160,342, Humphreys et 00 0o al, published November 6, 1985, discloses aqueous liquid bleaching compositions containing organic peroxyacid 2particles suspended in an acidic surfactant-structured liquid.

U.S. Patent 3,996,152, Edwards et al, issued December 7, 1976, discloses stable, low-pH gels contains'i ing peroxyacid bleach particles and a non-starch thicken- 1 30 ing agent.

U.S. Patent 4,100,095, Hutchins, issued July 11, 1978, discloses the stabilization of peroxyacid bleaches by the use of certain exotherm control agents.

Despite the above attempts to stabilize liquid diperoxyacid bleaching compositions, there is a continuing need for the development of physically and chemically ~i a~i i -2-

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ai cCsre C C C CC

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a.c C, o C £o i stable liquid diperoxyacid bleaches having a high level of diperoxyacid and a low viscosity.

Summary of the Invention The present invention relates to a stable liquid bleach composition comprising, by weight: from about 10% to about 25% of water-insoluble diperoxyacid particles of the formula HOOOC(CH2)nCOOOH, wherein n is from about 7 to about 14, said particles having an average size of from about 0.5 to about 15 microns; from about 2% to about on an acid basis, of a C 11

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13 linear alkylbenzene sulfonate surfactant; from about 0% to about on an acid basis, of 15 cumene sulfonate; from about 5% to about 15% of magnesium sulfate; from 0% to about 7% sodium or potassium sulfate; and from about 40% to about 78% water said composition containing from about 3% to about 14% of and from about 5% to about 16% of and and from about 12% to about 30% of and the weight ratio of to being less than about 3:1; 25 and said composition having a pH of from about 2 to about 4.5 and a viscosity of from about 50 to about 1000 cps at 20 0

C.

Detailed Description of the Invention The liquid bleach compositions herein contain 30 water-insoluble aliphatic diperoxyacid particles, C 11

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13 linear alkylbenzene sulfonate surfactant, cumene sulfonate as an optional ingredient, magnesium sulfate, sodium or potassium sulfate as an optional ingredient and water. These essential ingredients are combined at certain carefully balanced levels and ratios to obtain compositions having a high level of peroxyacid bleach, t- l i

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-3low product viscosity, and good physical and chemical stability. The compositions generally remain as stable suspensions having little or no separation of ingredients during storage, preferably for as long as 2 months at room temperature. The compositions also have chemical peroxyacid) stability of at least about 80%, with the preferred compositions having at least about stability after 2 months storage at room temperature.

The compositions of the present invention have a pH of from about 2 to about 4.5, preferably from about to about 4, most preferably from about 3 to about e, vwhen measured at 20 0 C for best peroxyacid bleach stabilc ity.

J n (The compositions also have a viscosity of from about cc c 15 50 to about 1000 cps, preferably from about 60 to about c 750 cps, more preferably from about 75 to about 500 cps, cj and most preferably from about 100 to about 350 cps, at when measured with an LTV Brookfield Viscometer, c using a No. 3 spindle and a setting of 60 rpm. This relatively low viscosity is desired for convenient pouring from a container by the user.

Seer The compositions of the present invention contain from about 10% to about 25%, preferably from about 12% to about 22%, more preferably from about 14% to about II 025 by weight, of substantially water-insoluble diperoxyacid S ,t particles of the formula HOOOC(CH 2 COOOH, wherein n is from about 7 to about 14, preferably from about 8 to 12.

~The particles have an average size of from about 0.5 to about 15, preferably from about 0.5 to about 10, microns.

A particularly preferred material is 1,12-diperoxydodecanedioic acid (DPDA).

The compositions contain from about 2% to about 6%, 4 preferably from about 2% to about by weight on an acid basis, of a water-soluble alkali metal, ammonium or alkylolammonium) C 1 1

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13 linear alkylbenzene sulfonate surfactant. The alkylbenzene sulfonate i T _1q% -4-

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C C tVC C 0

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o CC: Co C to to C t 4 4 ii C V i contributes to physical stability by dispersing the peroxyacid particles. However, since it also increases product viscosity, particularly when used at higher levels within the claimed range and when shorter carbon chain C 11 or C 12 alkylbenzene sulfonates are selected, the type and level of alkylbenzene sulfonate must be selected along with the other ingredients herein to provide the desired viscosity. The C13 alkylbenzene sulfonates are particularly preferred.

The compositions can also contain from 0% to about preferably from about 1% to about most preferably from about 2% to about by weight on an acid basis, of a water-soluble alkali metal, ammonium or alkylolammonium) cumene sulfonate. Cumene sulfonate also functions as a dispersant for the peroxyacid particles, and it significantly decreases viscosity. It thus can serve as a thinning agent and as a partial replacement for the C 11 -C13 linear alkylbenzene sulfonate surfactant.

The bleach compositions herein further contain from 20 about 5% to about 15%, preferably from about 8% to about 12%, by weight, of magnesium sulfate. The magnesium sulfate helps to suspend the diperoxyacid particles via density matching in range of from about 1.15 to about 1.22 g/ml. Magnesium sulfate also functions as an 25 effective exotherm control agent in the present compositions.

The compositions further contain from 0% to about preferably from about 2% to about by weight, of sodium sulfate or potassium sulf':, J. Sodium and 30 potassium sulfate, and to a lesser extent the cumene sulfonate, can be used to help match the density of, and thereby suspend, the peroxyacid particles. Mixtures of sodium or potassium sulfate, cumene sulfonate and magnesium sulfate are preferred to avoid adding excessive 35 magnesium hardness to the wash water. The mixture of these salts also appears to be more effective at ii

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physically stabilizing the peroxyacid particles since less of the mixture is required to stabilize the composition than when magnesium sulfate alone is used.

However, sodium and potLssium sulfate significantly increase viscosity, and so their use must be limited to meet the desired viscosity range.

Finally, the compositions contain from about 40% to about 78%, preferably from about 50% to about 70%, by weight, of water.

In addition to the above, the C 11

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13 alkylbenzene sulfonate and cumene sulfonate together should represent C ,CTt from about 3% to about 14%, preferably from about 4% to v T about 12%, most preferably from about 4% to about 10%, by I weight, of the composition to provide sufficient dispers- Scc 15 ant for the peroxyacid particles while maintaining the e c desired low viscosity.

tec The magnesium sulfate and sodium or potassium sulfate should represent from about 5% to about 16%, I, preferably from about 10% to about 15%, by weight of the t 20 composition in order to adequately suspend the peroxyacid particles. The weight ratio of magnesium sulfate to Ct to sodium or potassium sulfate is preferably from about 1:1 to about 4:1, more preferably from about 2:1 to about 3:1, for the desired combination of exotherm stability, J 25 low wash water hardness, and low viscosity.

The C 1-C13 alkylbenzene sulfonate, cumene sulfon- 11 13 Sate, magnesium sulfate and sodium or potassium sulfate i together should represent from about 12% to about -*preferably from about 14% to about 25%, by weight of the composition to provide sufficient dispersing and suspending agents.

The weight ratio of diperoxyacid particles to magnesium sulfate should also be less than about 3:1, 'preferably less than about 2.5:1, for best exotherm i 35 stability.

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*P 4 4 44 4i 4 The bleaching compositions of the present invention can, of course, be employed by themselves as bleaching agents. However, such compositions will more commonly be used as one element of a total bleaching or laundering composition.

Bleaching compositions herein can contain any of the optional ingredients known for use in such compositions.

The compositions herein can contain minor amounts, generally less than about preferably less than about most preferably less than about by weight, of other synthetic surfactants, such as other anionic, nonionic, cationic and zwitterionic surfactants, or mixtures thereof, known in the art. However, such additional surfactants, particularly nonionic and cationic surfactants, have been found to increase viscosity and to cause phase separation when used at higher levels, and thus are not preferred for use herein.

Preferably, the compositions are substantially free of such other surfactants.

20 Since the peroxyacid compounds used in the compositions of the present invention are subject to the loss of available oxygen when contacted by heavy metals, it is desirable to include a chelating agent in the compositions. Such agents are preferably present in an 25 amount ranging from 0.005% to about 1.0% by weight of the composition. The chelating agent can be any of the well-known agents, including those described in U.S.

Patent 3,442,937, issued May 6, 1969 to Sennewald et al., U. S. Patent 2,838,459, issued July 10, 1958 to Sprout, Jr., and U.S. Patent 3,192,255, issued June 29, 1965 to Cann. Preferred chelating agents are picolinic acid and dipicolinic acid.

Bleaching compositions of the present invention are utilized by adding them to water in an amount sufficient to provide from about 1.0 ppm to 100 ppm available oxygen in solution. Generally, this amounts to about 0.01% to -7-

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0 045C 4 04 oCB 00 4O 4 0* 0 49 0.4% by weight of composition in solution. Fabrics to be bleached are then contacted with such aqueous bleaching solutions.

The compositions of the present invention can also be used in combination with conventional fabric laundering detergent compositions. Such compositions can contain standard detergent ingredients, such as- the surfactants and builders described in U.S. Patent 4,100,095, Hutchins et al., issued July 11, 1978, incorporated herein by reference. Preferred detergent compositions are described in U.S. Patent 4,561,998, Wertz, et al., issued December 31, 1985, and U.S. Patent 4,507,219, Hughes, issued March 26, 1985, both incorporated herein by reference.

15 Preferably, detergent compositions formulated for use with bleaching compositions herein have a pH of from about 9 to about 12, preferably from about 9.5 to about 11.5, more preferably from about 10 to about 11. They preferably contain from about 2% to about 15%, more preferably from about 4% to about 10%, by weight, of monoethanolamine. The combination of such an alkaline composition with a bleaching composition herein preferably delivers a wash water pH of from about 7.8 to about 9, preferably from about 7.9 to about 8.5, which is desired for good bleaching performance, a minimum of fabric yellowing, and a minimum of bleach decomposition by the monoethanolamine.

The following examples illustrate the compositions of the present invention.

30 All parts, percentages and ratios used herein are by weight unless otherwise specified.

Example I The following composition was prepared by high shear mixing of the components in an Eppenbach mixer while in an ice bath. The DPDA and water were added to the mixer before turning the mixer on. The suds suppressor was 4 Vi -8-

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added to minimize foaming while mixing and to minimize air entrapment in the finish composition. The other components were added in the order listed at the indicated times after turning on the mixer.

Component Grams Wt.% Time 1,12-Diperoxydodecanedioic 10,821.6 18.0 0 acid (DPDA)(26.68% active slurry*) Water (additional) 1896 11.8 0 Suds suppressor 12.8 0.08 1 min.

St C 13 linear alkylbenzene 417.8 2.5 3 min.

sulfonic acid (96% active*) Sodium cumene sulfonate 463.4 1.45 3 min.

c 15 (50% active*) Cr Dipicolinic acid 1.6 0.01 3 min.

S Sodium sulfate 641.6 4.0 1 hr.25 min.

Magnesium sulfate 1684.2 10.5 2 hr.10 min.

Ce Sodium hydroxide (50% 104 0.32 3 hr.10 min.

20 active*) j c *Balance primarily water.

After 3 hr. 30 min., the pH of the composition was determined to be 3.20 at 200C. After 4 hr. 10 min., the pH was again determined to be 3.20 at 20 0 C and the mixer 4 25 was turned off. The composition was a stable suspension I It of the ingredients. It has a viscosity of about 350 cps at about 20°C. The DPDA had an average particle size of y ~about 2-5 microns.

A The above describes the preferred process for making the composition since high shear mixing of the components in an ice bath, their order of addition and the Sapproximate times of addition have all been found to be important to obtain the desired physical stability.

i:After 9 days, there still was no physical separation of the composition. A 951 gram sample of the composition was removed from the bottom and analyzed. It contained 7 11 i i

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C CCL 4* C -C C 44 -9- 18.29% DPDA and 10.81% magnesium sulfate. Since the target composition was 18.0% DPDA, chemical stability was very good.

After 11 days, about 48 grams of water were removed 5 from the bottom of the composition. Since this represents only about 0.3% of the composition, physical stability was very good.

After 18 days, the original composition was transferred, along with 5 other samples of similar composition and preparation, to a 55 gallon drum and mixed by hand.

The mixture was analyzed to contain 18.29% DPDA. It had a viscosity of about 350 cps, a density of 1.187 g/ml, and a pH of 3.20, all measured at 20 0 C. The next day, samples of the mixture were placed in storage at 15 (4.44 0 50 0 F (10 0 70 0 F (21.1 0 90 0 F (32.2 0 C) and 100 0 F (37.8 0

C).

After 17 days, the samples had very good physical and chemical stability, as indicated below.

Physical Stability 20 40 0 F OK. Very slight clear aqueous layer on top.

0 F OK. No separation.

OK. No separation.

90°F OK. Less than about 2% clear aqueous layer on bottom.

25 100°F Less than about 5% clear aqueous layer on bottom.

Chemical Stability 18.25% DPDA 70 0 F 18.21% DPDA 90 0 F 18.28% DPDA The above composition is preferably used in combination with the following detergent composition. The detergent composition was prepared by adding the following components to a mixing tank in the order listed with continuous mixing.

Components 11 0 0* 94* 94 8t 9.* I 9* 00 69 0 8o SO 0 oP 0 6004 o 4 .9,4 48 81 98 4 8 Sodium C14-15 alky polyethoxylate (2.25) sulfate

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13 linear alkylbenzene sulfonic acid Sodium diethylenetriamine pentaacetate Propylene glycol Monoethanolamine Brightener mix C12-13 alcohol polyethoxylate Ethanol 15 Potassium hydroxide Sodium hydroxide Boric Acid Water Sodium 2-dodecenyl 20 succinate C12-14 fatty acid Citric acid Calcium formate TEPA-E 15-18 25 pH trim to 10.5 Protease enzyme (2.0 AU/g) Amylase enzyme (375 AM. U/g) Perfume 30 Dye Water Assay 48.8 96.0 41.0 100.0 100.0 100.0 100.0 92.0 45.0 50.0 100.0 80.0 100.0 50.0 10.0 80.0 100.0 100.0 100.0 100.0 Wt. Product 11.3 8.0 0.35 10.5 5.0 9.0 10.48 2.48 2.94 1.25 5.53 3.5 4.0 0.12 3.0 1.16 0.16 0.25 0.08 to 100% Wt. Stock 23.21 8.33 0.7 10.5 6.21 2 7.3 5.51 5.88 1.25 5.65 6.9 1.2 3.75 1.16 0.16 0.25 0.08 3.25 li *^fes^^'iil l

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1 1 1 1 Paste also contains 16.2% ethanol and 35% water.

Contains 32.2% monoethanolamine, 32.2% water, 32.2%

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12 13 alcohol polyethoxylate and 3.36% of brightener.

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-11- Alcohol and monoethoxylated alcohol removed.

Tetraethylene pentaimine ethoylated with 15-18 moles (avg.) of ethylene oxide at each hydrogen site.

The compositions are preferably used in a volume ratio of detergent composition to liquid bleach of about 5.5:1. The detergent composition is designed for a usage level of about 0.55 cups in a typical U.S. laundering process. This delivers a concentration of product in the wash water of about 0.22% by weight. Usage of about 0.1 cups about 25 ml) of the liquid bleach would deliver about 10 ppm of available oxygen to the wash water. The detergent composition and liquid bleach are preferably simultaneously codispensed from a dual compartment bottle at a volume ratio of detergent to bleach 15 of about 5.5:1.

The mixture of the succinate and fatty acid builders in the above detergent composition is preferred because it causes less fabric yellowing and measuring cup residue than an all fatty acid formula when used with the above liquid bleach.

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e tf 00 8 6 6* Example II Other compositions of the present can be prepared as in Example I, are as Wt.% invention, which follows: 6a 6 25 Components A 1,12-Diperoxydodecanedioic 12.5 acid* 1,9-Diperoxyazelaic acid* Water 73.0

C

13 linear alkylbenzene 4.0 sulfonic acid

C

11 .4 linear alkylbenzene sulfonic acid Sodium cumene sulfonate Magnesium sulfate 6.6 Sodium sulfate 3.1

B

15.0 63.0 3.0 C D 25.0 21.0 ,56.0 65.0 13.0 10.5 2.5 9.2

*CM

-12- Potassium sulfate Suds suppressor 0.1 0.02 0.02 Dipicolinic acid 0.01 0.02 0.01 0.01 Sodium hydroxide to pH: 3.8 3.2 3.35 3.25 Viscosity (cps at 20 0 C) 450 900 *Average particle size about 2-5 microns, after preparation.

Within the range of 50-1000.

Example III After storage of an about 22.3 kg sample of the Sliquid bleach mixture of Example I for about 8 months at about 20 0 C, a clear aqueous layer (about 6 kg) was removed from the bottom of the sample and the remainder 1 15 was analyzed to contain the following: Components Wt. a, o 1,12-Diperoxydodecanedioic acid (DPDA) 16.3 Water 57.0 20 Suds suppressor 0.11 "o o C 13 linear alkylbenze sulfonic acid 3.4 Sodium cumene sulfonate 1.8 Dipicolinic acid 0.01 Sodium sulfate Magnesium sulfate 9.2 ,Miscellaneous balance The composition had a viscosity of about 850 cps, S. measured at 20 0 C. An additional 6.4 parts of sodium cumene sulfonate (50% active) was added to 100 parts of the composition to reduce its viscosity to about 240 cps at 20*C. This composition had a pH of about 2.6. Its pH was adjusted to about 3.15 by adding a 50% solution of sodium hydroxide, resulting in a finished liquid bleach composition containing about 15.5% DPDA.

-13- The above liquid bleach composition is preferably used in combination with the following liquid detergent composition, which was prepared by adding the components to a mixing tank in the order listed with continuous mixing.

Wt. Wt. Componen t s Assay Product Stock

C

13 linear alkylbenzene sulfonic acid 45.0 7.87 17.49 Sodium C 14 15 alkyl polyethoxylate (2.25) sulfate 48.4 11.86 24.512 Propylene glycol 100.0 8.38 3.53 U Sodium diethylenetriamine pentaacetate 41.0 0.30 0.73 Brightener mix 100.0 6.70 3 Monoethanolamine 100.0 4.5 2.50

SC

12 -1 3 alcohol polyethoxylate 100.0 4.93 2.93 Ethanol 92.0 3.94 t* 20 Sodium hydroxide 50.0 4.19 5.38 Potassium hydroxide 45.0 1.18 2.62 C 2-14 fatty acid 100.0 9.86 9.86 Citric acid 50.0 3.94 7.88 Calcium formate 10.0 0.12 1.20 o 25 Sodium formate 30.0 0.86 2.77

SC

12 alkyltrimethylammonium chloride 37.0 0.6 1.62

TEPA-E

1 5 1 8 80.0 1.97 2.46 pH trim to 10.5 Protease enzyme (2.0 AU/g) 100.0 0.74 0.74 Amylase enzyme (375 AM. U/g) 100.0 0.16 0.16 Dye 100.0 0.08 0.08 Perfume 100.0 0.25 0.25 Water to 100% 6.59 Paste also contains 1.4% sodium hydroxide, 8.44% monoethanolamine, 25% propylene glycol, and 20.16% water.

-14- 2 Paste also contains 16.2% ethanol, 5.12% sodium hydroxide, and 30.3% water.

3 Contains 7.46% monoethanolamine, 29.82% C 12 1 3 alcohol polyethoxylate 59.65% water, and 3.07% brightener.

Alcohol and monoethoxylated alcohol removed.

The compositions are preferably used in a volume ratio of detergent composition to liquid bleach of about 4:1. The detergent composition is designed for a usage level of about 0.5 cups in a tyical U.S. laundering process. This delivers a concentration of product in the wash water of about 0.2% by weight. Usage of about 0.125 15 cups about 30 ml) of the liquid bleach would deliver about 10 ppm of available oxygen to the wash water. The detergent composition and liquid bleach are preferably simultaneously codispensed from a single dosing, dual compartment cup at a volume ratio of detergent to bleach of about 4:1.

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Claims

1. A stable liquid bleach composition comprising, by weight: from 10% to 25% of water-insoluble diperoxyacid particles of the formula HOOOC(CH 2 nCOOOH, wherein n is from 7 to 14, said particles having an average size of from 0.5 to 15 microns; from 2% to on an acid basis, of a C11-C13 10 linear alkylbenzene sulfonate surfactant; from 0% to on an acid basis, of cumene sulfonate; tcr. from 5% to 15% of magnesium sulfate; from 0% to 7% sodium or potassium sulfate; and from 40% to 78% water c c said composition containing from 3% to 14% of and Ci\\ from 5% to 16% of and and from 12% to 30% of IC and the weight ratio of to being less than 3:1; and said composition having a pH of from 2 to and a viscosity of from 50 to 1000 cps at 20 0 C. c c c e C G ce C C o oa 000 0 30 0 30

2. A composition according to claim 1 wherein the diperoxyacid is 1,12-diperoxydodecanedioic acid.

3. A composition according to claim 2 comprising from 14% to 20% of 1,12-diperoxydodecanedioic acid.

4. A composition according to any one of the preceding claims wherein the diperoxyacid particles have an average size of from 0.5 to 10 microns.

5. A composition according to any one of the preceding claims wherein the composition has a viscosity of from 75 to 500 cps at

6. A composition according to any one of the preceding claims wherein is a C 13 linear alkylbenzene sulfonate. i IF 7 Ils~ 16

7. A composition according to claim 6 comprising from 2% to 4% of C 13 linear alkylbenzene sulfonate.

8. A composition according to claim 7 comprising from 8% to 12% of magensium sulfate and from 2% to 6% of sodium sulfate.

9. A composition according to any one of the preceding claims comprising from 1% to 6% of cumene sulfonate.

10. A composition according to any one of the preceding claims having a viscosity of from 100 to 350 cps at 20 0 C. t I

11. A composition according to any one of the preceding claims having a pH of from 3 to 3.5 at 20 C. E C t C eIg c

12. A composition according to claim 1 substantially as C z hereinbefore described with reference to any one of the C sCC examples. DATED: 24 May 1990 PHILLIPS ORMONDE FITZPA 0CK 9 Attorneys For: A d' ha THE PROCTER GAMBLE COMPANY 0O 0 (7359h) I c e 1 a' ij :j