IE60011B1

IE60011B1 - Stable liquid diperoxyacid bleach

Info

Publication number: IE60011B1
Application number: IE81487A
Authority: IE
Original assignee: Procter & Gamble
Priority date: 1986-03-31
Filing date: 1987-03-30
Publication date: 1994-05-18
Also published as: AU600263B2; JPS63399A; EP0240481B1; IE870814L; KR870009073A; SG99892G; AU7076187A; EP0240481A1; KR940006254B1; MX172458B; CA1294510C; HK104692A; GR3000789T3; GB8707571D0; GB2188654A; DE3763424D1; JP2528867B2

Abstract

Stable liquid bleach compositions containing diperoxyacid particles, C11-C13 linear alkylbenzene sulfonate surfactant, optional cumene sulfonate, magnesium sulfate, optional sodium or potassium sulfate, and water combined at certain carefully balanced levels and ratios. The compositions have a pH of from about 2 to about 4.5 and a viscosity of from about 50 to about 1000 cps at 20 DEG C.

Description

The present invention relates to stable liquid diperoxyacid bleach compositions useful for bleaching V fabrics, hard surfaces and other substrates» The compositions contain water-insoluble aliphatic diperoxyacid particles, C^- linear alkylbensen® sulfonate surfactant, cumene sulfonate as an optional ingredient, magnesium sulfate, sodium or potassium sulfate as an optional ingredient, and water. The compositions also have a pH of from 2 to 4.5 and a viscosity of from 50 to 1000 mPa.s at 20 °C. The ingredients are combined at certain carefully balanced levels and ratios, as hereinafter described, to provide compositions exhibiting good physical and chemical stability.

European Patent Application 160,342» Humphreys et al, published November 6» 1985» discloses aqueous liquid bleaching compositions containing organic peroxyacid particles suspended in an acidic surfactant-structured liquid. The disclosed compositions do not contain magnesium sulphate.

U.S. Patent 3,996.,152, . Edwards et al, issued December 7, 1976, discloses stable, low-pH gels containing peroxyacid bleach particles and a non-starch thickening agent.

U.S. Patent 4,100,095» Hutchins, issued July 11» 1978» discloses the stabilisation 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 stable liquid diperoxyacid bleaches having a high level of diperoxyacid and a low viscosity. i The present invention relates to a stable liquid bleach composition comprising, by weight: (a) from 10% to 25% of water-insoluble diperoxyacid particles of the formula HOOOC (CH2)nC000H, wherein n is from 7 to 14, said particles having an average size of from 0.5 to 15 micrometers,’ (b) from 2% to 6%, on an acid basis, of a water-soluble C-j-j-C-jg linear alkylbensene sulfonate surfactant; (c) from 0% to 8%, on an acid basis, of a watersoluble cumene sulfonate; (d) from 0% to 7% sodium or potassium sulfate; and (e) from 40% to 78% water; characterized in that it further contains from 5% to 15% of magnesium sulfate, provided that the total of (b) and (c) is 3% to 14%, the total of magnesium sulfate, sodium sulfate and potassium sulfate is from 5% to 16%, the total of (b), (c), magnesium sulfate, sodium sulfate and potassium sulfate is from 12% to 30%; the weight ratio of (a) to magnesium sulfate being less than 3:1; and said composition having a pH of from 2 to 4.5 and a viscosity of from 50 to 1000 mPa.s at 20 C, the viscosity being measured with an LTV Brookfield Viscometer, using a No.3 spindle and a setting of 60 rpm.

The liquid bleach compositions herein contain water-insoluble aliphatic diperoxyacid particles, linear alkylbensene 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, low 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 (i.e., peroxyacid) stability of at least about 80%, with the preferred compositions having at least about 901 stability after 2 months storage at room temperature.

The compositions of the present invention have a pK of from 2 to 4.5, preferably from 2.5 to 4, most preferably from 3 to 3-5, when measured at 20®C for best peroxyacid bleach stability.

The compositions also have a viscosity of from 50 to 1000 mPa.s, preferably from 60 to 750 mPa.s, more preferably from 75 to 500 mPa.s, and most preferably from 100 to 350 mPa.s, at ®Ct, when measured with an LTV Brookfield Viscometer, using a No. 3 spindle and a setting of SO rpm. This relatively low viscosity is desired for convenient pouring from a container by the user.

The compositions of the present invention contain from 10% to 25%, preferably from 12% to 22%, more preferably from 14% most preferably from 15% to % , %, by weight, particles to of water-insoluble diperoxyacid of the formula HOOOC(CFOCOOOH, wherein n is from l A to Th© 14, preferably from 8 to 12 particles have an average size of from 0.5 to 15, preferably from 0.5 to 1C, micrometers. A particularly preferred material is 1 „ 12-diperoxydodecanedioic acid (DPDA).

The compositions contain from preferably from 2% to acid basis, of a water-soluble ammonium or alkylolammoniura) C^-C, linear alkylbenzene sulfonate surfactant. The alkylbenzene sulfonate contributes to physical stability by dispersing the % to 6 %, 4%, by weight on an (e.g., alkali metal, I peroxyacid particles. However, since it also increases product viscosity, particularly when used at higher levels within the claimed range and when shorter carbon chain (e.g., C,, or 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 alkylbenzene sulfonates are particularly preferred.

The compositions can also contain from 0% to 8%, preferably from 1% to 6%, most preferably from 2% to 5%, by weight on an acid basis, of a water-soluble (e.g., 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, ,-C,3 linear alkylbenzene sulfonate surfactant. In certain compositions, the cumene sulfonate represents from 0% to 4%, preferably from 1% to 3%, by weight on an acid basis, of the composition.

The bleach compositions herein further contain from 5% to 15%, preferably from 3% to 12»·, by weight, of magnesium sulfate. The magnesium sulfate helps to suspend the diperoxyacia. particles via density matching in range of from 1.15 fo 1.22 g/ml. Magnesium sulfate also functions as an effective exotherm control agent in the present compositions.

The compositions further contain from 0% to 7», preferably from 2% to 6», by weight, of sodium sulfate or potassium sulfate. Sodium and 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 β magnesium hardness to the wash water. The mixture of these salts also appears to be more effective at 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 potassium sulfate significantly increase viscosity# and so their use must he limited to meet the desired viscosity range.

Finally# th® compositions contain from 40% to 78%, preferably from 50% to 70%, by weight# of water.

In addition to the above# ths C^-C^ alkylbenzene sulfonate and cumene sulfonate together should represent from 3% to 14%, preferably from 4% to 12%, most preferably from 4% to 10%, by weight# of the composition to provide sufficient dispersant for the peroxyacid 'particles while maintaining the desired low viscosity.. In certain compositions# the alkylbenzene sulfonate and cumene sulfonate together represent from 3% to 101# preferably from 3% to 8%, most preferably from 3.5% to 6%, by weight of the composition.

The magnesium sulfate and sodium or potassium sulfate should represent from preferably from 8% to from 101 to 15%, by weight of the composition in order to adequately suspend th® peroxyacid particles. Th® weight ratio of magnesium sulfate to sodium or potassium sulfate is preferably from 4:1, more preferably from 2s1 to desired combination of exotherm stability, low wash water hardness, and low viscosity.

The C^-C^ alkylbenzene sulfonate, cumene sulfonate, magnesium sulfate and sodium or potassium sulfate together should represent from 12% to 30%, preferably from 12% to 25%, mor© preferably % to 16%, 16%, more preferably 1:1 to 3:1, for the mixtures thereof, known additional surfactants, from 14% to 254, most preferably from 14% to 201, 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 3:1,, preferably less than . 2.5:1, for best exotherm stability.

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 compositionsThe compositions herein can contain minor amounts, generally less than 5%, preferably less than 2%, most preferably less than 1%, by weight, of other synthetic surfactants, such as other anionic, nonionic, cationic and zwitterionic surfactants, or in the art. However, such particularly nonionic and cationic surfactants, have been found to increase viscosity and to cause pha&e separation when used at higher levels, and thus are not preferred for use herein. Preferably, the compositions are substantially free of such other surfactants. The compositions herein generally contain less than 2%, preferably less than 1%, by weight, of other anionic synthetic surfactants. Preferably, the compositions are essentially free of such other anionic synthetic surfactants.

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 amount ranging from 0.005% to 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 1.0 ppm to 100 ppm, preferably from 1.0 ppm to 50 ppm, available oxygen in solution. Generally, this amounts to 0.01% to 0.4%, preferably from 0.01% to 0.2%, 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. 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..

Preferably, detergent compositions formulated for use with bleaching compositions herein have a pH of from 9 to 12, preferably from 9.5 11.5, more preferably from 10 to preferably contain from 2% to preferably from 4% to 10%, monoethanolamine. composition with preferably delivers a wash water pH of from 7.8 to to 11. They %, more by weight, of The combination of such an alkaline a bleaching composition herein 9, preferably from 7„9 to 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 th© compositions of the present invention.

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

Examole ϊ 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 added to minimise foaming while mixing and to minimize air entrapment in the finish composition. The other components were added in the order listed at the j indicated times after turning on the mixer. Component Grams Wt.% Time 1»12-Diperoxydodecanedioxc 10,821.6 18.0 0 acid (DPDAH26„68% active slurry*) Water (additional) 1895 11.8 .0 Suds suppressor 12.S 0.08 1 min. Cj, linear alkylbenzene 417.8 2.5 3 min. sulfonic acid (95% active*) Sodium cumene sulfonate 463.4 1.45 3 min. (50% active*! Dipicolinic acid 1.6 0.01 3 min. Sodium sulfate 641.6 4.0 1 hr»25 min. Magnesium sulfate 1634.2 10.5 2 hr.10 min. Sodium hydroxide (50% 104 0.32 3 hr.10 min. active*) «Balance primarily water.

After 3 hr. 30 min»» the pH of the composition was determined to be 3.20 at 20eC. After 4 hr. 10 min»» the pH was again determined to be 3»20 at 20*0 and the mixer was turned off- The composition was a stable suspension, of the ingredients. It had a viscosity of about 350 mPa.s at 20°C. The DPDA had an average particle size of 2-5 micrometers.

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 approximate times of addition have all been found to be important to obtain the desired physical stability.

After 9 days, there still was no physical separation of the composition. A S51 gram sample of the composition was removed from the bottom and analyzed. It contained 18.29% DPDA and 10.81% magnesium sulfate. Since the target composition was 18.0% DPDA, chemical stability was very good.

After 11 days, 48 grams of water were removed from the bottom of the composition. Since this represents only 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 (about 200 liters) drum and mixed by hand. The mixture was analyzed to contain 18.29% DPDA» It had a viscosity of about 350 mPa.s a density of 1.187 g/ml, and a pH of 3.20, all measured at 20*C. The next day, samples of the mixture were placed in storage at 40°P (4.44°Ci, 50°F ilO’C), 70eF (21.1°C), 9CPF (32.2eC) and 100°F (37.8eC).

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

Physical Stability 4.44°C - ok. Very slight clear aqueous layer on top.

°C- ok. No separation. 21.1°C„ ok. $o separation. 32.2°C- OK. Less than about 2% clear aqueous layer oa bottom. Π 37.8°C - Less than about 5% clear aqueous layer on bottom.

Chemical Stability °C - 18.25% DPDA 21.1°C - 18.21% DPDA 32.2 °C - 18.2 8% 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 Sodium alky polyethoxylate (2.25) sulfate Cj3 linear alkylbensene sulfonic acid Sodium diethylenetriamine pentaacetate Propylene glycol, Monoethanolamine Brightener mix cj9_i3 alcohol polyethoxylate (6.5)* Ethanol Potassium hydroxide Sodium hydroxide Boric Acid Water Sodium 2-dodecenyl succinate ci2-i4 fatty scid Citric acid Calcium formate TZ!>A-E15-18** % Wt. % Wt. % Assay Product Stock 48.8 11.3 23.21 96.0 8.0 8.33 41.0 0.35 0.7 100.0 10.5 10.5 100.0 5.0 3.0 100.0 6.21 100.0 9.0 7.0 92.0 10.48 7.3 45.0 2.48 5.51 50.0 2.94 5.88 100.0 1.25 1.25 5.65 80.0 5.53 6.9 100.0 3.5 3.5 50.0 4.0 8.0 10.0 0.12 1.2 80.0 3.0 3.75 pH trim to 10.5 - - Protease enzyme (2.0 AU/g, 100.0 1.16 1.16 Amylase enzyme (375 AM. U/g, 100.0 0.16 0.16 Perfume 100.0 0.25 0.25 Dye 100.0 0.08 0.08 Water - to 100% 3.251Paste also contains 16.2% ethanol and 35% water.

Contains 32.2% monoethanolamine, 32.2% water, 32.2% C12-i3 polyethoxylate (6.5) , and 3.36% of brightener.

* Alcohol and monoethoxylated alcohol removed.

Tetraethylene pentaimine ethoxylated 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 5.5:1. The detergent composition is designed for a usage level of about 0.55 cups (about 140 ml) 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 (i.e., 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 st a volume ratio of detergent to bleach Of 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.

Example II Other compositions of the present invention, which can be prepared as in Example I, are as follows: Wt.% Components A B C D 1 12~Diperoxydodecanedioic 12.5 - 25.0 21.0 acid* 1,9-Diperoxyazelaic acid* - 15.0 - - Water 73.0 63.0 56.0 65.0 linear alkylbenzene 4.0 3.0 4.0 - sulfonic acid C.j 1 Λ linear alkylbenzene - - - 3.0 sulfonic acid Sodium cumene sulfonate - 2.0 - - Magnesium sulfate 6.6 13.0 10.5 9.2 Sodium sulfate 3.1 - 2.5 - Potassium sulfate - - - 1.0 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 (mPa.s at 20°C) 450 A A 900 ** ‘Average particle size 2-5 micrometers# preparation.

Within the range of 50-1000.

Example III After storage of an about 22.3 kg sample of the liquid bleach mixture of Example I for 8 months at 20 °C, a clear aqueous layer (about 6 kg) was removed from the bottom of the sample and the remainder was analyzed to contain the following: Components Wt.% 1,12-Diperoxydodecanedioic acid (DPDA) 16.3 Water 57.0 Suds suppressor 0.11 C1^ linear alkylbenze sulfonic acid 3.4 Sodium cumene sulfonate 1.8 Dipicolinic acid 0.03 Sodium sulfate 3.5 Magnesium sulfate 9.2 Miscellaneous balance The composition had a viscosity of about 850 mPa.s measured at 20ttC. 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 mPa.s at 20eC. This composition had. a pH of 2.6. Its pH was adjusted to 3.15 by adding a 50% solution of sodium hydroxide, resulting in a finished liquid bleach composition containing 15.5% DPDA.

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.

Components % Assay wt, % Product Wt. % Stock C^3 linear alkylbenzene sulfonic acid 45.0 7.87 17.49 Sodium alkyl poly- ethoxylate (2.25} sulfate 48.4 11.06 24.51' Propylene glycol 100.0 8.38 3.53 Sodium diethylenetriamine pentaacetate 41.0 0.30 0.73 Brightener mix 100.0 6.70' Monoethanolamine 100.0 4.5 2.50 alcohol polyethoxylate <6.S>* 100.0 4.93 2.93 Ethanol 92.0 3.94 • Sodium hydroxide 50.0 4.19 5.38 Potassium hydroxide 45.0 1.18 2.S2ci9-.'(4 fatty acid 3.00.0 9.86 9.06 Citric acid 50.0 3.94 7.88 Calcium format© 10.0 0.12 1.20 >5 Sodium formate 30.0 0.86 2.77 alkyltrinethylammonium chloride 37.0 0.6 1.62'..TEPA-E1S-1S*’ pH trim to 10.5 80.0 1.97 2.4 6 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 1 Paste also contains 1.41 sodium hydroxide „ 8.< monoethanolamine, 25% propylene glycol, and 20.161 water.

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

^Contains 7.46% monoethanolamine, 29.82% C10-12 alcohol polyethoxylate (6„5)% 59.65% water, and 3.07% brightener.

* Alcohol and monoethoxylated alcohol removed.

** Tetraethylene pentaimine ethoxylated 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 . 4s 1. The detergent composition is designed for a usage level of about 0.5 cups (about 125 ml) in a typical 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 cups (i.e-, 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 T4;l.

Claims

1. A stable liquid bleach composition comprising, by weight : (a) froa 10% to 25% of water-insoluble diperoxyacid particles of tha formula HCCOCfCHpJ^COCOH, wherein n is from 7 to 14, said (, particles having an average size of from 0.5 to 15 micrometers ; (to) from 2% to 5%, on an acid basis, of a water-soluble C ir C 13 linear alkylbenzene sulfonate surfactant? (c) from 0% to 8%, on an acid basis, of a water-soluble cumene sulfonate; (d) from 0% to 7% sodium or potassium sulfate; and (e) from 40% to 78% water; characterised in that it further contains from 5% to 15% of magnesium sulfate, provided that the total of (to) and (c) is from 3% to 14%; the total of magnesium sulfate, sodium sulfate and potassium sulfate is from 5% to 16%; and the total of (to), (c), magnesium sulfate, sodium sulfat® and potassium sulfate is from 12% to 30%; the weight ratio of (a) to magnesium sulfate being less than 3x1; and said composition having a pH of from 2 to 4.5 and a viscosity of from 50 to 1000 mPa.s at 20°C, the viscosity being measured with an LTV Brookfield Viscometer, using a No. 3 spindle and a setting of 50 rpm.

2. The composition of claim 1 wherein the diperoxyacid is 1,12-diperoxydodecanedioic acid.

3. The composition of claim 1 wherein the diparoxyacid particles have an average size of from 0.5 to 10 ? micrometers. t ί

4. The composition of claim X wherein (b) is a C 13 linear alkylbenzene sulfonate.

5. The composition of claim 1 wherein the composition has a viscosity of from 75 to 500 mPa.s at 20°C. 5» The composition of claim 5 wherein (to) is a C 13 linear alkylbensene sulfonate» 5 7. The composition of claim S comprising from 2% to 4% of C 13 linear aXkylbanzene sulfonate and from 1% to 6% of cumene sulfonate. 3. The composition of claim 7 comprising from 3% to 12% of magnesium sulfate and from 2% to 6% of sodium sulfate.

6. 9« The composition of claim 8 comprising from 14% to

7. 10 20% of the 1»1.2-diperoxydodecanedioic acid. 10. The composition of claim 9 having a viscosity of from 100 to 350 mPa.s at 20°C.

8. 11. A stable liquid bleach composition according to claim 1, substantially as hereinbefore described with

9. 15 particular reference to the accompanying Examples.