Classifications

• • C—CHEMISTRY; METALLURGY
  • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
  • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
  • C11D17/00—Detergent materials or soaps characterised by their shape or physical properties
  • C11D17/06—Powder; Flakes; Free-flowing mixtures; Sheets
  • C11D17/065—High-density particulate detergent compositions

Definitions

• the present invention relates to improving the dissolution of a granular detergent composition, especially in cold temperature laundering solutions (i.e., less than about 30°C). More particularly, the detergent composition contains particles having optimally selected physical properties, such as particle size, particle density and concentration of detergent ingredients, for achieving improved dissolution performance.
• clumps are especially prevalent under cold temperature washing conditions and/or when the order of addition to the washing machine is laundry detergent first, clothes second and water last (commonly known as the "Reverse Order Of Addition” or "ROOA").
• ROOA Reverse Order Of Addition
• this clumping phenomenon can contribute to the incomplete dispensing of detergent in washing machines equipped with dispenser drawers or in other dispensing devices, such as a granulet. In this case, the undesired result is undissolved detergent residue in the dispensing device.
• inorganic salts In addition to the viscous surfactant "bridging" effect, inorganic salts have a tendency to hydrate which can also cause “bridging” of particles which linked together via hydration. In particular, inorganic salts hydrate with one another to form a cage structure which exhibits poor dissolution and ultimately ends up as a "clump" after the washing cycle. It would therefore be desirable to have a detergent composition which does not experience the dissolution problems identified above so as to result in improved cleaning performance.
• the invention meets the needs above by providing a detergent composition which has improved dissolution in laundering solutions, especially in solutions kept at cold temperatures (i.e., less than about 30°C).
• a combination of optimally selected physical properties of various particulate detergent ingredients in a detergent composition is used to achieve improved dissolution performance.
• the detergent composition comprises from about 1% to about 50%, based on the total number of discrete particles in the composition, of substantially "sticky particles" with certain composition, size and density specifications.
• the substantially sticky particles contain at least about 15%, by weight of the sticky particles, of a "substantially sticky surfactant.”
• the substantially sticky particles have a geometric mean particle diameter size of from about 300 microns to about 700 microns with a geometric standard deviation of less than about 1.8, and a bulk density of at least about 450 g/1.
• the composition includes at least about 35%, based on the total number of discrete particles in the admixture composition, of substantially non-sticky particles having a geometric mean particle diameter size of from about 200 microns to about 500 microns with a geometric standard deviation of greater than about 1.2 and a bulk density of less than about 850 g/1.
• the substantially non-sticky particles may include inorganic fillers, builders, "substantially non-sticky surfactants" and other ingredients.
• the non-sticky particles will have a substantially low to nil (i.e., less than about 10% on a weight basis) concentration of sticky surfactants.
• the total amount of surfactants, including both sticky and non- sticky surfactants, in the composition is at least about 15% by weight of the composition.
• a method of laundering clothes comprising the steps of contacting soiled clothes with an effective amount of a detergent composition according to compositions described herein in an aqueous washing solution is also provided.
• the invention provides a detergent composition which exhibits improved dispersion and dissolution in aqueous laundering solutions. It has been found that by optimally selecting physical properties of various particles contained in granular detergent compositions, the dissolution can be improved. As mentioned previously, typical detergent formulations that dissolve in aqueous laundering solutions form highly viscous surfactant phase or paste which binds or otherwise "bridges” other surfactant-containing particles together into “clumps” ultimately causing "lump-gel” formation.
• the phrase "discrete particles” means individual particles, agglomerates or granules which can be identified via a scanning electron microscope as discrete units of mass. For each type of particle component in an admixture, the discrete particles of that type have the same or substantially similar composition regardless of whether the particles are in contact with other particles. For agglomerated components, the agglomerates themselves are considered as discrete particles and each discrete particle may be comprised of a composite of smaller primary particles and binder compositions.
• the phrase "geometric mean particle diameter” means the geometric mass average diameter of a set of discrete particles as measured by any standard mass-based particle size measurement technique, such as dry sieving.
• the phrase "geometric standard deviation" of a particle size distribution means the geometric breadth of the best-fitted log-normal function to the above-mentioned particle size data.
• the phrase “builder” means any inorganic material having “builder” performance in the detergency context, and specifically, organic or inorganic material capable of removing water hardness from washing solutions.
• the term “bulk density” refers to the uncompressed, untapped powder bulk density, as measured by pouring an excess of powder sample through a funnel into a smooth metal vessel (e.g., a 500 ml volume cylinder), scraping off the excess from the heap above the rim of the vessel, measuring the remaining mass of powder and dividing the mass by the volume of the vessel.
• the term "substantially sticky surfactants” refers to a surfactant or surfactant blend system consisting primarily of surfactants which substantially contribute lump-gel formation in cold temperature washing solutions, including the general classes of alkyl benzene sulfonates, alkyl ethoxy sulfates, and nonionic surfactants.
• the phrase “substantially non-sticky surfactant” refers to a surfactant or surfactant blend system consisting primarily of surfactants which do not substantially contribute to lump-gel formation in cold temperature washing solutions, such as linear-chain alkyl sulfates with an average alkyl carbon chain length of at least 12.
• all specifications of level of composition and size distribution are done on a mass basis unless otherwise specified. In cases where level is specified on a number basis, the calculations used to convert from a mass to number basis are contained in Example III set forth hereinafter.
• the level of the non-sticky particles is based on the total number of discrete particles in the detergent composition.
• the physical properties, such as particle size and distribution and density, of the substantially non-sticky particles are also optimally selected. It should be imderstood that the "discrete particles" which contain surfactants or other ingredients such as inorganic builders can be in the form of admixed particles, spray-dried granules, and/or agglomerates, depending upon the desired overall formulation and product density.
• the particle size of the sticky particles should not be extremely large such that they require an inordinate amount of time before which they dissolve in the aqueous laundering solution.
• the particle size of the substantially non-sticky particles should not be extremely small and have a very low density such that the detergent composition is extremely "dusty”.
• the balance between the larger substantially sticky particles and the smaller substantially non-sticky particles should be selected so as to avoid significant product segregation in the detergent product box prior to use.
• the present invention provides an optimal selection of the various physical properties to provide the desired improved dissolution performance improvement.
• the mass-based geometric mean particle size diameter of the substantially sticky particles is preferably of from about 300 microns to about 700 microns with a geometric standard deviation of less than about 1.8, more preferably of from about 350 microns to about 650 microns with a geometric standard deviation of less than about 1.7, and most preferably about 400 microns to about 600 microns with a geometric standard deviation of less than about 1.6.
• Preferred compositions include substantially sticky particles having at least about 15%, more preferably from about at least about 35%, and most preferably at least about 45%, by weight of the sticky particles, of a substantially sticky surfactant.
• an especially preferred substantially sticky surfactant is a potassium salt of a surfactant selected from the group consisting of linear alkyl benzenes, alkyl ethoxy sulfates, and mixtures thereof.
• the average bulk density of the substantially sticky particles is preferably at least about 450 g/1, more preferably at least about 550 g/1, and most preferably at least about 650 g/1.
• the geometric mean particle size diameter of the substantially non- sticky particles is preferably of from about 200 microns to about 500 microns with a geometric standard deviation of greater than about 1.2, more preferably of from about 250 microns to about 450 microns with a geometric standard deviation of greater than about 1.4, more preferably of from about 300 microns to about 400 microns with a geometric standard deviation of greater than about 1.6.
• Preferred compositions include inorganic builder-containing particles having less than about 10%, more preferably less than about 5%, and most preferably less than about 1%, by weight of the non-sticky particles, of a substantially sticky surfactant.
• the average bulk density of the non-sticky particles is preferably less than about 850 g/1, more preferably less than about 650 g/1, and most preferably less than about 500 g/1.
• non-sticky particles comprise sodium or potassium salts selected from the group consisting of sodium chloride, sodium carbonate, sodium sulfate, tetrasodium pyrophosphate, trisodium pyrophosphate, disodium pyrophosphate, monosodium pyrophosphate, potassium chloride, potassium carbonate, potassium sulfate, tetrapotassium pyrophosphate, tripotassium pyrophosphate, dipotassium pyrophosphate, monopotassium pyrophosphate and mixtures thereof.
• sodium or potassium salts selected from the group consisting of sodium chloride, sodium carbonate, sodium sulfate, tetrasodium pyrophosphate, trisodium pyrophosphate, disodium pyrophosphate, monosodium pyrophosphate, potassium chloride, potassium carbonate, potassium sulfate, tetrapotassium pyrophosphate, tripotassium pyrophosphate, dipotassium pyr
• composition comprises from about 0.05% to about 50% by weight of potassium preferably from about 0.5% to about 30%, more preferably from about 1% to about 20%, by weight, of potassium ions, regardless of the source from which the potassium ions derive.
• potassium ions useful herein are derived from potassium salts.
• the potassium salts useful herein are potassium salts of alkali builders (e.g. potassium salt of carbonates, potassium salt of silicates), potassium salt of mid-chain branched surfactants, and mixtures thereof.
• inorganic potassium salts are preferred, and are more preferably selected from the group consisting of potassium chloride (KG), potassium carbonate (K 7 CO 3 ), potassium sulfate (K SO ), and mixtures thereof. These are commercially available. Potassium carbonate is most preferred.
• Inorganic potassium salts may include dehydrated (preferably) or hydrated tetrapotassium pyrophosphate (K P O ; preferred), tripotassium pyrophosphate (HK P O ), dipotassium pyrophosphate
• potassium salts for use herein are dehydrated (preferably) or hydrated pentapotassium tripolyphosphate (K P O ), tetrapotassium tripolyphosphate (K P O ), tetrapotassium tripolyphosphate (HK P O ), tripotassium tripolyphosphate (H K P O ), dipotassium tripolyphosphate (H K P O ), and monopotassium tripolyphosphate (H KP O ); potassium hydroxide (KOH); potassium silicate; and potassium neutralized surfactant such as potassium longer alkyl chain, mid chain-branched surfactant compounds, liner potassium alkylbenzene sulfonate, potassium alkyl sulfate, and or potassium alkylpolyethoxylate.
• salts of film forming polymers as described in U.S. Pat. No. 4,379,080, Murphy, issued Apr. 5, 1983, column 8, line 44 to column 10, line 37, incorporated herein, which are either partially or wholly neutralized with potassium.
• Particularly preferred are the potassium salts of copolymers of acrylamide and acrylate having a molecular weight between about 4,000 and 20,000.
• the combination of both types of the aforementioned particles must net an overall particle size distribution that has less than about 5% fine and less than about 5% oversize particles, where the fine limit is defined at 150 microns and the oversize limit is defined at 1180 microns.
• Nonlimiting examples of the preferred substantially sticky surfactants include anionic surfactants which include the conventional Cj j-Cjg alkyl benzene sulfonates, branched-chain and random C10-C20 a lkyl sulfates, the CJQ-CI S secondary (2,3) alkyl sulfates of the formula CH3(CH 2 ) x (CHOSO 3 " M + ) CH 3 and CH 3
• x and (y + 1) are integers of at least about 7, preferably at least about 9, and M is a water-solubilizing cation, especially sodium or potassium, unsaturated sulfates such as oleyl sulfate, and the C ⁇ Q-C ⁇ g alkyl alkoxy sulfates ("AE X S"; especially EO 1-7 ethoxy sulfates).
• exemplary surfactants useful include and Cio-C j alkyl alkoxy carboxylates (especially the EO 1-5 ethoxycarboxylates), the C J O-18 glycerol ethers, the Cl0"Cl8 alkyl polyglycosides and their corresponding sulfated polyglycosides, and Ci2-C] alpha-sulfonated fatty acid esters.
• the conventional nonionic and amphoteric surfactants such as the Cj2-C ⁇ alkyl ethoxylates including the so-called narrow peaked alkyl ethoxylates and Cg-C ⁇ alkyl phenol alkoxylates (especially ethoxylates and mixed ethoxy/propoxy), C ⁇ -Cjg betaines and sulfobetaines ("sultaines"), C ⁇ Q-C ⁇ amine oxides, and the like, can also be included in the overall compositions.
• the CjQ-Ci N-alkyl polyhydroxy fatty acid amides can also be used. Typical examples include the Ci2-C ⁇ g N-methylglucamides. See WO 9,206,154.
• sugar-derived surfactants include the N-alkoxy polyhydroxy fatty acid amides, such as C 10"C 18 N-(3-methoxypropyl) glucamide.
• the N-propyl through N-hexyl C ⁇ 2-C ⁇ g glucamides can be used for low sudsing.
• C ⁇ 0-C20 conventional soaps may also be used.
• the branched-chain C 1 o-C 1 soaps may be used. Mixtures of anionic and nonionic surfactants are especially useful. Other conventional useful surfactants are listed in standard texts.
• Inorganic Builders A variety inorganic builders are suitable for use herein and include aluminosilicates, crystalline layered silicates, MAP zeolites, citrates, amorphous silicates, sodium carbonates and mixtures thereof.
• the aluminosilicate ion exchange materials used herein as a detergent builder preferably have both a high calcium ion exchange capacity and a high exchange rate.
• the aluminosilicate ion exchange materials used herein are preferably produced in accordance with Corkill et al, U.S. Patent No. 4,605,509 (Procter & Gamble), the disclosure of which is incorporated herein by reference.
• the aluminosilicate ion exchange material is in "sodium" form since the potassium and hydrogen forms of the instant aluminosilicate do not exhibit the as high of an exchange rate and capacity as provided by the sodium form.
• the aluminosilicate ion exchange material preferably is in over dried form so as to facilitate production of crisp detergent agglomerates as described herein.
• the aluminosilicate ion exchange materials used herein preferably have particle size diameters which optimize their effectiveness as detergent builders.
• particle size diameter represents the average particle size diameter of a given aluminosilicate ion exchange material as determined by conventional analytical techniques, such as microscopic determination and scanning electron microscope (SEM).
• the preferred particle size diameter of the aluminosilicate is from about 0.1 micron to about 10 microns, more preferably from about 0.5 microns to about 9 microns. Most preferably, the particle size diameter is from about 1 microns to about 8 microns.
• the aluminosilicate ion exchange material has the formula
• aluminosilicates are available commercially, for example under designations Zeolite A, Zeolite B and Zeolite X.
• Naturally-occurring or synthetically derived aluminosilicate ion exchange materials suitable for use herein can be made as described in Krummel et al, U.S. Patent No. 3,985,669, the disclosure of which is incorporated herein by reference.
• the aluminosilicates used herein are further characterized by their ion exchange capacity which is at least about 200 mg equivalent of CaCO 3 hardness/gram, calculated on an anhydrous basis, and which is preferably in a range from about 300 to 352 mg equivalent of CaCO 3 hardness/gram. Additionally, the instant aluminosilicate ion exchange materials are still further characterized by their calcium ion exchange rate which is at least about 2 grains Ca ⁇ /gallon/minute/-gram/gallon, and more preferably in a range from about 2 grains
• crystalline layered sodium silicates exhibit a clearly increased calcium and magnesium ion exchange capacity.
• the layered sodium silicates prefer magnesium ions over calcium ions, a feature necessary to insure that substantially all of the "hardness" is removed from the wash water.
• These crystalline layered sodium silicates are generally more expensive than amorphous silicates as well as other builders. Accordingly, in order to provide an economically feasible laundry detergent, the proportion of crystalline layered sodium silicates used must be determined judiciously.
• the crystalline layered sodium silicates suitable for use herein preferably have the formula
• the crystalline layered sodium silicate has the formula
• Adjunct ingredients include other detergency builders, bleaches, bleach activators, suds boosters or suds suppressors, anti-tarnish and anticorrosion agents, soil suspending agents, soil release agents, germicides, pH adjusting agents, non-builder alkalinity sources, chelating agents, smectite clays, enzymes, enzyme-stabilizing agents and perfumes. See U.S.
• Water-soluble, nonphosphorus organic builders useful herein include the various alkali metal, ammonium and substituted ammonium polyacetates, carboxylates, polycarboxylates and polyhydroxy sulfonates.
• polyacetate and polycarboxylate builders are the sodium, potassium, lithium, ammonium and substituted ammonium salts of ethylene diamine tetraacetic acid, nitrilotriacetic acid, oxydisuccinic acid, mellitic acid, benzene polycarboxylic acids, and citric acid.
• Polymeric polycarboxylate builders are set forth in U.S. Patent 3,308,067, Diehl, issued March 7, 1967, the disclosure of which is incorporated herein by reference.
• Such materials include the water-soluble salts of homo- and copolymers of aliphatic carboxylic acids such as maleic acid, itaconic acid, mesaconic acid, fumaric acid, aconitic acid, citraconic acid and methylene malonic acid.
• Some of these materials are useful as the water-soluble anionic polymer as hereinafter described, but only if in intimate admixture with the non-soap anionic surfactant.
• polyacetal carboxylates for use herein are the polyacetal carboxylates described in U.S. Patent 4,144,226, issued March 13, 1979 to Crutchfield et al, and U.S. Patent 4,246,495, issued March 27, 1979 to Crutchfield et al, both of which are incorporated herein by reference.
• These polyacetal carboxylates can be prepared by bringing together under polymerization conditions an ester of glyoxylic acid and a polymerization initiator. The resulting polyacetal carboxylate ester is then attached to chemically stable end groups to stabilize the polyacetal carboxylate against rapid depolymerization in alkaline solution, converted to the corresponding salt, and added to a detergent composition.
• Particularly preferred polycarboxylate builders are the ether carboxylate builder compositions comprising a combination of tartrate monosuccinate and tartrate disuccinate described in U.S. Patent 4,663,071, Bush et al., issued May 5, 1987, the disclosure of which is incorporated herein by reference.
• Bleaching agents and activators are described in U.S. Patent 4,412,934, Chung et al., issued November 1, 1983, and in U.S. Patent 4,483,781, Hartman, issued November 20, 1984, both of which are incorporated herein by reference.
• Chelating agents are also described in U.S. Patent 4,663,071, Bush et al., from Column 17, line 54 through Column 18, line 68, incorporated herein by reference.
• Suds modifiers are also optional ingredients and are described in U.S. Patents 3,933,672, issued January 20, 1976 to Bartoletta et al., and 4,136,045, issued January 23, 1979 to Gault et al., both incorporated herein by reference.
• Suitable smectite clays for use herein are described in U.S. Patent 4,762,645, Tucker et al, issued August 9, 1988, Column 6, line 3 through Column 7, line 24, incorporated herein by reference.
• Suitable additional detergency builders for use herein are enumerated in the Baskerville patent, Column 13, line 54 through Column 16, line 16, and in U.S. Patent 4,663,071, Bush et al, issued May 5, 1987, both incorporated herein by reference.
• LAS means C 12 . 14 linear alkylbenzene sulfonate surfactant
• AS means C 14 . 15 alkyl sulfate surfactant
• 65/25/10 is a percentage weight ratio:
• the spray-dried granules are prepared using a standard spray drying process in which the ingredients are mixed together to form a slurry which is then sprayed into a spray drying tower to form spray dried granules.
• the detergent agglomerates are prepared by combining the surfactant paste and other ingredients together in one or more mixers until detergent agglomerates are formed.
• the admixed components are simply added to the granules and agglomerates if it a dry ingredient and sprayed on if in liquid form.
• the various physical properties of the compositions are shown below:
• the Control composition is a typical detergent composition having about 90% of substantially sticky particles (spray dried granules plus agglomerates) based on the total number of particles in the composition.
• the Control composition has a high number of sticky particle contact points which renders it susceptible to "bridging" effects ultimately causing lump-gel formation.
• the Example I and II compositions only contain sticky surfactants in the higher-density agglomerates, and therefore, have about 30% or fewer sticky particles, based on the total number of particles in the composition.
• Examples I and II have a much better ROOA ("Reverse Order Of Addition") grade and experience less residual mass in the washing machine and on the clothes subsequent to standard laundering operations.
• ROOA Reverse Order Of Addition
• This Example illustrates one of the many means by which the particle number percentage of sticky particles and/or non-sticky particles can be determined relative to the total number of discrete particles in the composition.
• the input variables describe the physical characteristics of each admixture component within the mixture: w, weight of component i in the composition; d, geometric mean particle size on a mass basis; 1 ⁇ , geometric standard deviation of the particle size distribution on a mass basis; pi bulk density.
• the weight fraction of each mixture component, w j5 is converted to the total mixture volume fraction, V,. This is done using an intermediate volume, v condiment and the component bulk density, p ⁇ (eq. Al).
• the component volumes are normalized to total mixture volume fractions (eq. A2).
• V j - ; volume fraction of component i in mixture (A2)
• a numerical method is used to convert the massed-based distribution to a number basis. For each component (i), consider a range of n size class values (j), x, j , where:
• the log-normal distribution describes a differential mass fraction per log(size), y tJ , as follows (eq. A5).
• the number density, n,, of component i particles is defined as the population of component (i) particles per unit volume of mixture; this is the product of the volume fraction and the sum of the (i) populations over all size classes, j (eq. A7).
• the number fraction, N is calculated by normalizing the number population over all components in the mixture (eq. A8). The number percent is simply the number fraction times 100.

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  • 1998-01-13 WO PCT/US1998/000567 patent/WO1999036503A1/en active IP Right Grant
  • 1998-01-13 CA CA002318491A patent/CA2318491C/en not_active Expired - Fee Related
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  • 1998-01-13 JP JP2000540207A patent/JP2002509187A/ja active Pending
  • 1998-01-13 CN CN98813090.4A patent/CN1285868A/zh active Pending
  • 1998-01-13 BR BR9814589-4A patent/BR9814589A/pt not_active IP Right Cessation
  • 1998-01-13 DE DE69825487T patent/DE69825487T2/de not_active Expired - Lifetime
• 1999
  • 1999-01-13 AR ARP990100109A patent/AR014301A1/es not_active Application Discontinuation

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